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Southern root-knot nematode (Meloidogyne incognita) and Fusarium wilt fungus (Fusarium oxysporum) are one of the most predominant pathogens responsible for substantial agricultural yield reduction of tomato. The current study planned to assess the effects of M. incognita (Mi) and F. oxysporum (Fo) and their co-infection on two tomato cultivars, Zhongza 09 (ZZ09) and Gailing Maofen 802 (GLM802). The present study examined the effects of co-infection on leaf morphology, chlorophyll content, leaf area, and histopathology. The present study used metabolomics to evaluate plant-pathogen interactions. The outcomes of the current study revealed that chlorophyll content and leaf area decreased more in GLM802 during co-infection. In co-infection (Fo + Mi), the chlorophyll content reduction in ZZ09 was 11%, while in GLM802 the reduction reached up to 31% as compared to control. Moreover, the reduction in leaf are in ZZ09 was 31%, however, in the GLM802 reduction was observed 54% as compared to control plants. Similarly, GLM802 stems exhibited larger brown patches on their vascular bundles than ZZ09 stems. The rate of browning of GLM802 stems was 247% more than ZZ09, during co-infection. Moreover, GLM802 roots exhibited a higher abundance of hyphae and larger galls than ZZ09 roots. In metabolic studies, glutathione, succinic acid, and 2-isopropylmalic acid decreased, whereas spermine and fumaric acid increased in GLM802 co-infected stems. It indicates that GLM802 is weakly resistant; therefore, F. oxysporum and other pathogens readily damage tissue. In the co-infected stem of ZZ09, L-asparagine and shikimic acid increased, but pipecolic acid, L-saccharine, and 2-isopropylmalic acid declined. L-asparagine was crucial in preserving the stability of nitrogen metabolism, chlorophyll synthesis, and leaf growth in ZZ09. Shikimic acid's substantial accumulation could explain the limited extent of browning observed in the vascular bundles of ZZ09. Thus, the present study provides insight into M. incognita and F. oxysporum co-infection in two tomato cultivars, which may aid breeding efforts to generate commercially viable resistant cultivars. However, further research on the relationship between M. incognita and F. oxysporum in different host plants is required in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Introduction: The human immunodeficiency virus (HIV) and tuberculosis (TB) co-infection presents significant challenges due to the complex interplay between these diseases, leading to exacerbated metabolic disturbances. Understanding these metabolic profiles is crucial for improving diagnostic and therapeutic approaches., Objective: This study aimed to characterise the urinary acylcarnitine and amino acid profiles, including 5-hydroxyindoleacetic acid (5-HIAA), in patients co-infected with HIV and TB using targeted liquid chromatography mass spectrometry (LC-MS) metabolomics., Methods: Urine samples, categorised into HIV, TB, HIV/TB co-infected, and healthy controls, were analysed using HPLC-MS/MS. Statistical analyses included one-way ANOVA and a Kruskal-Wallis test to determine significant differences in the acylcarnitine and amino acid profiles between groups., Results: The study revealed significant metabolic alterations, especially in TB and co-infected groups. Elevated levels of medium-chain acylcarnitines indicated increased fatty acid oxidation, commonly associated with cachexia in TB. Altered amino acid profiles suggested disruptions in protein and glucose metabolism, indicating a shift towards diabetes-like metabolic states. Notably, TB was identified as a primary driver of these changes, affecting protein turnover, and impacting energy metabolism in co-infected patients., Conclusion: The metabolic profiling of HIV/TB co-infection highlights the profound impact of TB on metabolic pathways, which may exacerbate the clinical complexities of co-infection. Understanding these metabolic disruptions can guide the development of targeted treatments and improve management strategies, ultimately enhancing the clinical outcomes for these patients. Further research is required to validate these findings and explore their implications in larger, diverse populations., (© 2024. The Author(s).)

Introduction: Amid the global health crisis, HIV/TB co-infection presents significant challenges, amplifying the burden on patients and healthcare systems alike. Metabolomics offers an innovative window into the metabolic disruptions caused by co-infection, potentially improving diagnosis and treatment monitoring., Aim: This study uses untargeted metabolomics to investigate the urinary metabolic signature of HIV/TB co-infection, enhancing understanding of the metabolic interplay between these infections., Methods: Urine samples from South African adults, categorised into four groups - healthy controls, TB-positive, HIV-positive, and HIV/TB co-infected - were analysed using GCxGC-TOFMS. Metabolites showing significant differences among groups were identified through Kruskal-Wallis and Wilcoxon rank sum tests., Results: Various metabolites (n = 23) were modulated across the spectrum of health and disease states represented in the cohorts. The metabolomic profiles reflect a pronounced disruption in biochemical pathways involved in energy production, amino acid metabolism, gut microbiome, and the immune response, suggesting a bidirectional exacerbation between HIV and TB. While both diseases independently perturb the host's metabolism, their co-infection leads to a unique metabolic phenotype, indicative of an intricate interplay rather than a simple additive effect., Conclusion: Metabolic profiling revealed a unique metabolic landscape shaped by HIV/TB co-infection. The findings highlight the potential of urinary differential metabolites for co-infection, offering a non-invasive tool for enhancing diagnostic precision and tailoring therapeutic interventions. Future research should focus on expanding sample sizes and integrating longitudinal analyses to build upon these foundational insights, paving the way for metabolomic applications in combating these concurrent pandemics., (© 2024. The Author(s).)

Candida albicans and Staphylococcus aureus are two commonly associated pathogens that cause nosocomial infections with high morbidity and mortality. Our prior and current work using a murine model of polymicrobial intra-abdominal infection (IAI) demonstrates that synergistic lethality is driven by Candida-induced upregulation of functional S. aureus α-toxin leading to polymicrobial sepsis and organ damage. In order to determine the candidal effector(s) mediating enhanced virulence, an unbiased screen of C. albicans transcription factor mutants was undertaken revealing that zcf13Δ/Δ fails to drive augmented α-toxin or lethal synergism during co-infection. A combination of transcriptional and phenotypic profiling approaches shows that ZCF13 regulates genes involved in pentose metabolism, including RBK1 and HGT7 that contribute to fungal ribose catabolism and uptake, respectively. Subsequent experiments reveal that ribose inhibits the staphylococcal agr quorum sensing system and concomitantly represses toxicity. Unlike wild-type C. albicans, zcf13Δ/Δ did not effectively utilize ribose during co-culture or co-infection leading to exogenous ribose accumulation and agr repression. Forced expression of RBK1 and HGT7 in the zcf13Δ/Δ mutant fully restores pathogenicity during co-infection. Collectively, our results detail the interwoven complexities of cross-kingdom interactions and highlight how intermicrobial metabolism impacts polymicrobial disease pathogenesis with devastating consequences for the host., (© 2024. The Author(s).)

The symptomatology of COVID-19 is dependent on the immune status and the cytokine response of the host. The cytokine level of the host is influenced by the presence of chronic persistent or latent infections with co-pathogens. Parasitic diseases are known to induce host immune-modulation which may impact the response to co-infection. Toxoplasmosis is a widespread protozoal infection that remains quiescent in its latent form to be re-activated during states of immune depression. Clinical data on the relation between toxoplasmosis and COVID-19 cytokine profile and symptomatology are still insufficient. Seventy-nine subjects were included in this study. Patients were diagnosed with COVID-19 by PCR. Serological testing for toxoplasmosis was performed by the detection of anti-Toxoplasma IgG antibodies, in addition to IgG avidity testing. IFN-γ and TNF-α levels were determined by RT-PCR. Among patients diagnosed with COVID-19, 67.1% were seronegative for anti-Toxoplasma IgG, while 32.9% were seropositive. High avidity was found in 10 cases (40% of seropositive cases), 4 of whom required ICU administration, while low avidity was found in 15 cases (60%), 7 of which were administered to the ICU. TNF-α and INF-γ levels were significantly higher in COVID-19 patients than in healthy control subjects. No significant association was found between the seroprevalence of toxoplasmosis and the presence of COVID-19 and its severity. Cytokines were significantly higher in both seropositive and seronegative COVID-19 patients than in their control counterparts. The high prevalence of toxoplasmosis merits further exploration of its relation to COVID-19 by mass studies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Context: Vancomycin (VCM), an important antibiotic against refractory infections, has been used to treat secondary infections in severe COVID-19 patients. Regrettably, VCM treatment has been associated with nephrotoxicity. Vitamin D 3 can prevent nephrotoxicity through its antioxidant effect., Objective: This study tests the antioxidant effect of vitamin D 3 in the prevention of VCM-induced nephrotoxicity., Materials and Methods: Wistar Albino rats (21) were randomly divided into 3 groups: (A) control; (B) VCM 300 mg/kg daily for 1 week; and (C) VCM plus vitamin D 3 500 IU/kg daily for 2 weeks. All the rats were sacrificed and serum was separated to determine kidney function parameters. Their kidneys were also dissected for histological examination and for oxidative stress markers., Results: Lipid peroxidation, creatinine, and urea levels decreased significantly ( p  < 0.0001) in the vitamin D 3 -treated group (14.46, 84.11, 36.17%, respectively) compared to the VCM group that was given VCM (MIC<2 μg/mL) only. A significant increase was observed in superoxide dismutase levels in the vitamin D 3 -treated group ( p  < 0.05) compared to rats without treatment. Furthermore, kidney histopathology of the rats treated with vitamin D 3 showed that dilatation, vacuolization and necrosis tubules decreased significantly ( p  < 0.05) compared with those in the VCM group. Glomerular injury, hyaline dystrophy, and inflammation improved significantly in the vitamin D 3 group ( p  < 0.001, p  < 0.05, p  < 0.05, respectively) compared with the VCM group., Discussion and Conclusions: Vitamin D 3 can prevent VCM nephrotoxicity. Therefore, the appropriate dose of this vitamin must be determined, especially for those infected with COVID-19 and receiving VCM, to manage their secondary infections.

Importance: Miscommunication of antiviral and antibacterial immune signals drives worsened morbidity and mortality during respiratory viral-bacterial coinfections. Extracellular vesicles (EVs) are a form of intercellular communication with broad implications during infection, and here we show that epithelium-derived EVs released during the antiviral response impair the antibacterial activity of macrophages, an innate immune cell crucial for bacterial control in the airway. Macrophages exposed to antiviral EVs display reduced clearance of Staphylococcus aureus as well as altered inflammatory signaling and anti-inflammatory metabolic reprogramming, thus revealing EVs as a source of dysregulated epithelium-macrophage crosstalk during coinfection. As effective epithelium-macrophage communication is critical in mounting an appropriate immune response, this novel observation of epithelium-macrophage crosstalk shaping macrophage metabolism and antimicrobial function provides exciting new insight and improves our understanding of immune dysfunction during respiratory coinfections., Competing Interests: The authors declare no conflict of interest.

Mycobacterium tuberculosis ( Mtb ) and HIV are known to mutually support each other during co-infection by multiple mechanisms. This synergistic influence could be either by direct interactions or indirectly through secreted host or pathogen factors that work in trans. Mtb secretes several virulence factors to modulate the host cellular environment for its persistence and escaping cell-intrinsic immune responses. We hypothesized that secreted Mtb transcription factors that target the host nucleus can directly interact with host DNA element(s) or HIV LTR during co-infection, thereby modulating immune gene expression, or driving HIV transcription, helping the synergistic existence of Mtb and HIV. Here, we show that the Mtb -secreted protein, EspR, a transcription regulator, increased mycobacterial persistence and HIV propagation during co-infection. Mechanistically, EspR localizes to the nucleus of the host cells during infection, binds to its putative cognate motif on the promoter region of the host IL-4 gene, activating IL-4 gene expression, causing high IL-4 titers that induce a Th2-type microenvironment, shifting the macrophage polarization to an M2 state as evident from CD206 dominant population over CD64. This compromised the clearance of the intracellular mycobacteria and enhanced HIV propagation. It was interesting to note that EspR did not bind to HIV LTR, although its transient expression increased viral propagation. This is the first report of an Mtb transcription factor directly regulating a host cytokine gene. This augments our understanding of the evolution of Mtb immune evasion strategies and unveils how Mtb aggravates comorbidities, such as HIV co-infection, by modulating the immune microenvironment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yandrapally, Agarwal, Chatterjee, Sarkar, Mohareer and Banerjee.)

Dendritic cells (DCs) are professional antigen-presenting cells (APCs) with the unique ability to mediate inflammatory responses of the immune system. Given the critical role of DCs in shaping immunity, they present an attractive avenue as a therapeutic target to program the immune system and reverse immune disease disorders. To ensure appropriate immune response, DCs utilize intricate and complex molecular and cellular interactions that converge into a seamless phenotype. Computational models open novel frontiers in research by integrating large-scale interaction to interrogate the influence of complex biological behavior across scales. The ability to model large biological networks will likely pave the way to understanding any complex system in more approachable ways. We developed a logical and predictive model of DC function that integrates the heterogeneity of DCs population, APC function, and cell-cell interaction, spanning molecular to population levels. Our logical model consists of 281 components that connect environmental stimuli with various layers of the cell compartments, including the plasma membrane, cytoplasm, and nucleus to represent the dynamic processes within and outside the DC, such as signaling pathways and cell-cell interactions. We also provided three sample use cases to apply the model in the context of studying cell dynamics and disease environments. First, we characterized the DC response to Sars-CoV-2 and influenza co-infection by in-silico experiments and analyzed the activity level of 107 molecules that play a role in this co-infection. The second example presents simulations to predict the crosstalk between DCs and T cells in a cancer microenvironment. Finally, for the third example, we used the Kyoto Encyclopedia of Genes and Genomes enrichment analysis against the model's components to identify 45 diseases and 24 molecular pathways that the DC model can address. This study presents a resource to decode the complex dynamics underlying DC-derived APC communication and provides a platform for researchers to perform in-silico experiments on human DC for vaccine design, drug discovery, and immunotherapies., Competing Interests: TH is the majority stakeholder in Discovery Collective, Inc. with proprietary rights to Cell Collective. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Aghamiri, Puniya, Amin and Helikar.)

Objective: To analyze the characteristics of peripheral blood lymphocyte subsets in systemic lupus erythematosus (SLE) patients with infection and non-infection group. Explore the risk factors of infection in SLE patients and establish a risk matrix model to predict the occurrence of co-infection., Methods: total of 333 SLE patients without infection, 163 patients suffering from infection, and 132 healthy controls (HCs) were recruited. General clinical data and disease activity indicators were collected. The levels of total T, B, CD4 + T, CD8 + T, NK, Th1, Th2, Th17, and Treg cells in peripheral blood of HCs, SLE patients (including infected and non-infected group) were analyzed by flow cytometry. The risk assessment model was constructed, and the receiver operating characteristic curve was drawn. 39 SLE patients with infection and 20 patients without infection were randomly selected to evaluate the predictive power of the regression model., Results: The levels of T, B, CD4 + T, CD8 + T, and NK cells in the infected patients were significantly decreased when compared with that of both non-infected patients and HCs ( p < .05). The non-infected patients had a higher level of Th17 than that of HCs ( p < . 05), but the absolute numbers of Th17 in infected patients was the lowest among the three groups ( p < .001). The number of Treg cells in SLE patients was significantly lower than that of HCs ( p < .01), and the infected patients had the fewest Treg cells among all these groups ( p < . 05). A risk assessment model for SLE with infection was established, p = 1/(1 - e -y ), Y = 1.763-0.004 × Absolute number of CD4 + T cells-0.005 × Absolute number of NK cells -0.005 × Platelet count(×10 12 /L) + 1.033 × Absolute number of lymphocytes (×10 9 /L) + 0.023 × C-reactive protein (mg/dL), whose predictive sensitivity is 77.5%, and specificity is 78.3%., Conclusion: The new risk assessment model exhibits good predictive ability to assess co-infection risk in SLE patients. T cells, NK cells, and CD4 + T cells along with other parameters help in differentiating Lupus with infection from Lupus alone.

In severe bacterial infections, there is a pro-inflammatory response to promote bacterial clearance but this response can cause tissue injury. Later, the immune system becomes dysregulated and the host is unable to clear a secondary or a pre-existing infection. Specialized Pro-resolving Mediators (SPMs) such as resolvin D2 (RvD2) have been shown to be beneficial for inflammation/infection resolution in animal models of sepsis but in vivo mechanisms by which RvD2 may promote bacterial clearance and/or attenuate deleterious effects of a secondary infection have not been fully established. In this study, we used the 2-hit model of cecal ligation and puncture (CLP) induced infectious peritonitis and secondary lung infection with Pseudomonas aeruginosa to find possible antimicrobial and immunomodulatory mechanisms of RvD2. We show that RvD2 given as late as 48h after CLP surgery reduced blood bacterial load without altering plasma cytokines compared to mice given saline vehicle. RvD2 increased splenic neutrophil accumulation as well as average reactive oxygen species (ROS) production. There was also an increase in an immature leukocyte population the myeloid derived suppressor cells (MDSCs) in the spleen of RvD2 treated mice. RvD2 reduced lung lavage bacterial load 24h after P. aeruginosa administration and significantly decreased lung lavage levels of IL-23, a cytokine essential in the Th-17 inflammatory response. In addition, we show that RvD2 increased the number of non-inflammatory alveolar macrophages after P. aeruginosa administration compared to saline treated mice. The study uncovered an antimicrobial mechanism of RvD2 where RvD2 increases mature neutrophil and MDSC accumulation into the spleen to promote blood bacterial clearance. The study showed that in this 2-hit model, RvD2 promotes lung bacterial clearance, increased non-inflammatory alveolar macrophage number and inhibits an adaptive immune pathway providing evidence of its resolution mechanism in secondary pulmonary infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sundarasivarao, Walker, Rodriguez, Spur and Yin.)

Trypanosoma cruzi is the causative protozoan of Chagas' Disease, a neglected tropical disease that affects 6-7 million people worldwide. Interaction of the parasite with the host immune system is a key factor in disease progression and chronic symptoms. Although the human immune system is capable of controlling the disease, the parasite has numerous evasion mechanisms that aim to maintain intracellular persistence and survival. Due to the pronounced genetic variability of T. cruzi , co-infections or mixed infections with more than one parasite strain have been reported in the literature. The intermodulation in such cases is unclear. This study aimed to evaluate the co-infection of T. cruzi strains G and CL compared to their individual infections in human macrophages derived from THP-1 cells activated by classical or alternative pathways. Flow cytometry analysis demonstrated that trypomastigotes were more infective than extracellular amastigotes (EAs) and that strain G could infect more macrophages than strain CL. Classically activated macrophages showed lower number of infected cells and IL-4-stimulated cells displayed increased CL-infected macrophages. However, co-infection was a rare event. CL EAs decreased the production of reactive oxygen species (ROS), whereas G trypomastigotes displayed increased ROS detection in classically activated cells. Co-infection did not affect ROS production. Monoinfection by strain G or CL mainly induced an anti-inflammatory cytokine profile by decreasing inflammatory cytokines (IFN-γ, TNF-α, IL-1β) and/or increasing IL-4, IL-10, and TGF-β. Co-infection led to a predominant inflammatory milieu, with reduced IL-10 and TGF-β, and/or promotion of IFN-γ and IL-1β release. Infection by strain G reduced activation of intracellular signal transducer and activator of transcription (STAT) factors. In EAs, monoinfections impaired STAT-1 activity and promoted phosphorylation of STAT-3, both changes may prolong cell survival. Coinfected macrophages displayed pronounced activation of all STATs examined. These activations likely promoted parasite persistence and survival of infected cells. The collective results demonstrate that although macrophages respond to both strains, T. cruzi can modulate the intracellular environment, inducing different responses depending on the strain, parasite infective form, and co-infection or monoinfection. The modulation influences parasite persistence and survival of infected cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Oliveira, Bonturi, Salu, Oliva, Mortara and Orikaza.)

In the development of sepsis, there is early, massive inflammation which can lead to multiple organ failure. Later there is an immunosuppressed phase where the host is susceptible to secondary infections or is unable to clear existing infection. Specialized Pro-resolving Mediators (SPMs) are endogenously produced lipids which resolve infection by decreasing bacteria load and reducing systemic inflammatory response. There has been little work studying if SPMs given late, can promote host defense. We examined if an SPM, Resolvin D2 (RvD2) could promote host defense in a 2-hit mouse model of cecal ligation and puncture (CLP) sepsis and secondary Pseudomonas aeruginosa lung infection. RvD2 given 48 h after mild CLP (1st hit), increased gene expression of Toll-like receptor-2 (TLR-2) and alveolar macrophage/monocyte phagocytic ability compared to CLP mice given saline vehicle. In this model, RvD2 did not affect plasma IL-6 or IL-10. These effects induced by RvD2, lowered lung bacterial load and decreased mortality after the secondary infection of Pseudomonas aeruginosa (2nd hit). Splenic T-cell numbers were also increased in RvD2 treated mice compared to saline vehicle treated animals. The results suggest that RvD2 promoted mechanisms of host defense in a 2-hit model sepsis and secondary lung infection., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Studies using the nonhuman primate model of Mycobacterium tuberculosis/simian immunodeficiency virus coinfection have revealed protective CD4+ T cell-independent immune responses that suppress latent tuberculosis infection (LTBI) reactivation. In particular, chronic immune activation rather than the mere depletion of CD4+ T cells correlates with reactivation due to SIV coinfection. Here, we administered combinatorial antiretroviral therapy (cART) 2 weeks after SIV coinfection to study whether restoration of CD4+ T cell immunity occurred more broadly, and whether this prevented reactivation of LTBI compared to cART initiated 4 weeks after SIV. Earlier initiation of cART enhanced survival, led to better control of viral replication, and reduced immune activation in the periphery and lung vasculature, thereby reducing the rate of SIV-induced reactivation. We observed robust CD8+ T effector memory responses and significantly reduced macrophage turnover in the lung tissue. However, skewed CD4+ T effector memory responses persisted and new TB lesions formed after SIV coinfection. Thus, reactivation of LTBI is governed by very early events of SIV infection. Timing of cART is critical in mitigating chronic immune activation. The potential novelty of these findings mainly relates to the development of a robust animal model of human M. tuberculosis/HIV coinfection that allows the testing of underlying mechanisms.

Neutrophils are recognized as important circulating effector cells in the pathophysiology of severe coronavirus disease 2019 (COVID-19). However, their role within the inflamed lungs is incompletely understood. Here, we collected bronchoalveolar lavage (BAL) fluids and parallel blood samples of critically ill COVID-19 patients requiring invasive mechanical ventilation and compared BAL fluid parameters with those of mechanically ventilated patients with influenza, as a non-COVID-19 viral pneumonia cohort. Compared with those of patients with influenza, BAL fluids of patients with COVID-19 contained increased numbers of hyperactivated degranulating neutrophils and elevated concentrations of the cytokines IL-1β, IL-1RA, IL-17A, TNF-α, and G-CSF; the chemokines CCL7, CXCL1, CXCL8, CXCL11, and CXCL12α; and the protease inhibitors elafin, secretory leukocyte protease inhibitor, and tissue inhibitor of metalloproteinases 1. In contrast, α-1 antitrypsin levels and net proteolytic activity were comparable in COVID-19 and influenza BAL fluids. During antibiotic treatment for bacterial coinfections, increased BAL fluid levels of several activating and chemotactic factors for monocytes, lymphocytes, and NK cells were detected in patients with COVID-19 whereas concentrations tended to decrease in patients with influenza, highlighting the persistent immunological response to coinfections in COVID-19. Finally, the high proteolytic activity in COVID-19 lungs suggests considering protease inhibitors as a treatment option.

Influenza A Virus (IAV), Staphylococcus aureus (staphylococci), and Streptococcus pneumoniae (pneumococci) are leading viral and bacterial causes of pneumonia. Dendritic cells (DCs) are present in the lower respiratory tract. They are characterized by low expression of co-stimulatory molecules, including CD80 and CD86 and high capacity of antigen uptake. Subsequently, DCs upregulate co-stimulatory signals and cytokine secretion to effectively induce T-cell priming. Here, we investigated these processes in response to bacterial and viral single as well as coinfections using human monocyte-derived (mo)DCs. Irrespective of single or coinfections, moDCs matured in response to IAV and/or staphylococcal infections, secreted a wide range of cytokines, and activated CD4+, CD8+ as well as double-negative T cells. In contrast, pneumococcal single and coinfections impaired moDC maturation, which was characterized by low expression of CD80 and CD86, downregulated expression of CD40, and a mild cytokine release resulting in abrogated CD4+ T-cell activation. These actions were attributed to the cholesterol-dependent cytotoxin pneumolysin (Ply). Infections with a ply-deficient mutant resulted in restored moDC maturation and exclusive CD4+ T-cell activation. These findings show that Ply has important immunomodulatory functions, supporting further investigations in specific modalities of Ply-DC interplay., (© 2022 The Author(s). Published by S. Karger AG, Basel.)

Successful pathogens require metabolic flexibility to adapt to diverse host niches. The presence of co-infecting or commensal microorganisms at a given infection site can further influence the metabolic processes required for a pathogen to cause disease. The Gram-positive bacterium Staphylococcus aureus and the polymorphic fungus Candida albicans are microorganisms that asymptomatically colonize healthy individuals but can also cause superficial infections or severe invasive disease. Due to many shared host niches, S. aureus and C. albicans are frequently co-isolated from mixed fungal-bacterial infections. S. aureus and C. albicans co-infection alters microbial metabolism relative to infection with either organism alone. Metabolic changes during co-infection regulate virulence, such as enhancing toxin production in S. aureus or contributing to morphogenesis and cell wall remodeling in C. albicans . C. albicans and S. aureus also form polymicrobial biofilms, which have greater biomass and reduced susceptibility to antimicrobials relative to mono-microbial biofilms. The S. aureus and C. albicans metabolic programs induced during co-infection impact interactions with host immune cells, resulting in greater microbial survival and immune evasion. Conversely, innate immune cell sensing of S. aureus and C. albicans triggers metabolic changes in the host cells that result in an altered immune response to secondary infections. In this review article, we discuss the metabolic programs that govern host-pathogen interactions during S. aureus and C. albicans co-infection. Understanding C. albicans-S. aureus interactions may highlight more general principles of how polymicrobial interactions, particularly fungal-bacterial interactions, shape the outcome of infectious disease. We focus on how co-infection alters microbial metabolism to enhance virulence and how infection-induced changes to host cell metabolism can impact a secondary infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Eichelberger and Cassat.)

Most clinical and experimental studies have suggested that hepatitis C virus (HCV) is dominant over hepatitis B virus (HBV) during coinfection, although the mechanism remains unclear. Here, we found that HCV core protein inhibits HBV replication by downregulating HBx levels during coinfection in human hepatoma cells. For this effect, HCV core protein increased reactive oxygen species levels in the mitochondria and activated the ataxia telangiectasia mutated-checkpoint kinase two pathway in the nucleus, resulting in an upregulation of p53 levels. Accordingly, HCV core protein induced p53-dependent activation of seven in absentia homolog one expression, an E3 ligase of HBx, resulting in the ubiquitination and proteasomal degradation of HBx. The effect of the HCV core protein on HBx levels was accurately reproduced in both a 1.2-mer HBV replicon and in vitro HBV infection systems, providing evidence for the inhibition of HBV replication by HCV core protein. The present study may provide insights into the mechanism of HCV dominance in HBV- and HCV-coinfected patients.

Despite the development of efficient anti-human immunodeficiency virus-1 (HIV-1) therapy, HIV-1 associated pathogens remain a major clinical problem. Human cytomegalovirus (CMV) is among the most common HIV-1 copathogens and one of the main causes of persistent immune activation associated with dysregulation of the immune system, cerebrovascular and cardiovascular pathologies, and premature aging. Here, we report on the development of dual-targeted drugs with activity against both HIV-1 and CMV. We synthesized seven compounds that constitute conjugates of molecules that suppress both pathogens. We showed that all seven compounds exhibit low cytotoxicity and efficiently inhibited both viruses in cell lines. Furthermore, we chose a representative compound and demonstrated that it efficiently suppressed replication of HIV-1 and CMV in human lymphoid tissue ex vivo coinfected with both viruses. Further development of such compounds may lead to the development of dual-targeted anti-CMV/HIV-1 drugs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1) and human cytomegalovirus (HCMV) may occur during pregnancy, labor, or breastfeeding. These viruses from amniotic fluid, cervicovaginal secretions, and breast milk may simultaneously interact with oropharyngeal and tonsil epithelia; however, the molecular mechanism of HIV-1 and HCMV cotransmission through the oral mucosa and its role in MTCT are poorly understood. To study the molecular mechanism of HIV-1 and HCMV MTCT via oral epithelium, we established polarized infant tonsil epithelial cells and polarized-oriented ex vivo tonsil tissue explants. Using these models, we showed that cell-free HIV-1 and its proteins gp120 and tat induce the disruption of tonsil epithelial tight junctions and increase paracellular permeability, which facilitates HCMV spread within the tonsil mucosa. Inhibition of HIV-1 gp120-induced upregulation of mitogen-activated protein kinase (MAPK) and NF-κB signaling in tonsil epithelial cells, reduces HCMV infection, indicating that HIV-1-activated MAPK and NF-κB signaling may play a critical role in HCMV infection of tonsil epithelium. HCMV infection of tonsil epithelial cells also leads to the disruption of tight junctions and increases paracellular permeability, facilitating HIV-1 paracellular spread into tonsil mucosa. HCMV-promoted paracellular spread of HIV-1 increases its accessibility to tonsil CD4 T lymphocytes, macrophages, and dendritic cells. HIV-1-enhanced HCMV paracellular spread and infection of epithelial cells subsequently leads to the spread of HCMV to tonsil macrophages and dendritic cells. Our findings revealed that HIV-1- and HCMV-induced disruption of infant tonsil epithelial tight junctions promotes MTCT of these viruses through tonsil mucosal epithelium, and therapeutic intervention for both HIV-1 and HCMV infection may substantially reduce their MTCT. IMPORTANCE Most HIV-1 and HCMV MTCT occurs in infancy, and the cotransmission of these viruses may occur via infant oropharyngeal and tonsil epithelia, which are the first biological barriers for viral pathogens. We have shown that HIV-1 and HCMV disrupt epithelial junctions, reducing the barrier functions of epithelia and thus allowing paracellular penetration of both viruses via mucosal epithelia. Subsequently, HCMV infects epithelial cells, macrophages, and dendritic cells, and HIV-1 infects CD4 + lymphocytes, macrophages, and dendritic cells. Infection of these cells in HCMV- and HIV-1-coinfected tonsil tissues is much higher than that by HCMV or HIV-1 infection alone, promoting their MTCT at its initial stages via infant oropharyngeal and tonsil epithelia.

To describe the clinical features and the risk factors for nontuberculous mycobacteria (NTM) and Talaromyces marneffei (TM) co-infections in HIV-negative patients. A multicenter retrospective study in 13 hospitals, and a systematic literature review were performed of original articles published in English related to TM/NTM co-infections. HIV-negative patients with TM and NTM co-infections comprised Group 1; TM-only infection Group 2; NTM-only infection Group 3; and healthy volunteers Group 4. Univariate logistic analysis was used to estimate the potential risk factors of TM/NTM co-infections. A total of 22 cases of TM and NTM co-infections were enrolled. Of these, 17 patients (77.3%) had a missed diagnosis of one of the TM or NTM pathogens. The anti-IFN-γ autoantibodies (AIGAs) titer, white blood cell (WBC), neutrophil counts (N), erythrocyte sedimentation rate (ESR), C reactive protein (CRP), globulin, and immunoglobulin G (IgG) levels of Group 1 were higher than those of the other groups, whereas the levels of CD4 + T cells was lower than those of other groups. There was a significant negative correlation between the AIGA titers and the number of CD4 + T cells (P < 0.05). Factors including the ratio of the actual values to the cut-off values of AIGAs, WBC, N, HGB, CD4 + T cells, IgG, IgM, IgA, serum globulin, ESR, and CRP were taken as potential risk factors for TM and NTM co-infection. Most patients with TM and NTM co-infection had a missed diagnosis of one of the TM or NTM pathogens. The levels of AIGAs, WBC, N, ESR, and CRP in TM and NTM co-infections were remarkably higher than in mono-infection. High-titer AIGAs may be a potential risk factor and susceptibility factor for co-infection of TM and NTM in HIV-negative hosts., (© 2021. The Author(s).)

Calcium dysregulation and mitochondrial dysfunction are key elements in the development of sepsis-induced cardiac dysfunction. Evidences have suggested that inhibition of Wnt/β-Catenin signalling prevents cardiac dysfunction and remodelling in surgical, hypertension and pressure overload models. The present study investigated the effects of Wnt/β-Catenin inhibitor on calcium overload and mitochondrial dysfunction in rat sepsis model of cardiomyopathy. Induction of sepsis by cecal ligation puncture (CLP) resulted in the up-regulation of cardiac β-catenin transcriptional levels and cardiac dysfunction depicted by increased serum lactate dehydrogenase, CK-MB levels reduced maximum (dp/dt max.) and minimum developed pressure (dp/dt min.), increased LVEsDP and relaxation constant tau values. Moreover, oxidative and inflammatory stress, immune cell infiltration, increased myeloperoxidase activity, enhanced caspase-3 activity and fibronectin protein levels were observed in septic rat's heart. Also, septic rat's heart displayed mitochondrial dysfunction due to mPTP opening, increased calcium up-regulation in left ventricular apex tissues and whole heart, increased collagen staining, necrosis and structural damage. Pre-treatment with Wnt/β-Catenin antagonist attenuated sepsis-induced serum and tissue biochemical changes, cardiac dysfunction and structural alterations by inhibiting mitochondrial mPTP opening and restricting calcium overloading in cardiac tissue.

To understand the possible role of mixed-prion infections in disease presentation, the current study reports the co-infection of sheep with bovine spongiform encephalopathy (BSE) and scrapie. The bovine BSE agent was inoculated subcutaneously into sheep with ARQ/ARQ or VRQ/ARQ PRNP genotypes either at the same time as subcutaneous challenge with scrapie, or three months later. In addition, VRQ/VRQ sheep naturally infected with scrapie after being born into a scrapie-affected flock were challenged subcutaneously with BSE at eight or twenty one months-of-age. Sheep were analysed by incubation period/attack rate, and western blot of brain tissue determined the presence of BSE or scrapie-like PrP Sc . Serial protein misfolding cyclic amplification (sPMCA) that can detect very low levels of BSE in the presence of an excess of scrapie agent was also applied to brain and lymphoreticular tissue. For VRQ/ARQ sheep challenged with mixed infections, scrapie-like incubation periods were produced, and no BSE agent was detected. However, whilst ARQ/ARQ sheep developed disease with BSE-like incubation periods, some animals had a dominant scrapie western blot phenotype in brain, but BSE was detected in these sheep by sPMCA. In addition, VRQ/VRQ animals challenged with BSE after natural exposure to scrapie had scrapie-like incubation periods and dominant scrapie PrP Sc in brain, but one sheep had BSE detectable by sPMCA in the brain. Overall, the study demonstrates for the first time that for scrapie/BSE mixed infections, VRQ/ARQ sheep with experimental scrapie did not propagate BSE but VRQ/VRQ sheep with natural scrapie could propagate low levels of BSE, and whilst BSE readily propagated in ARQ/ARQ sheep it was not always the dominant PrP Sc strain in brain tissue. Indeed, for several animals, a dominant scrapie biochemical phenotype in brain did not preclude the presence of BSE prion.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is leading to public health crises worldwide. An understanding of the pathogenesis and the development of treatment strategies is of high interest. Recently, neutrophil extracellular traps (NETs) have been identified as a potential driver of severe SARS-CoV-2 infections in humans. NETs are extracellular DNA fibers released by neutrophils after contact with various stimuli and accumulate antimicrobial substances or host defense peptides. When massively released, NETs are described to contribute to immunothrombosis in acute respiratory distress syndrome and in vascular occlusions. Based on the increasing evidence that NETs contribute to severe COVID-19 cases, DNase treatment of COVID-19 patients to degrade NETs is widely discussed as a potential therapeutic strategy. Here, we discuss potential detrimental effects of NETs and their nuclease degradation, since NET fragments can boost certain bacterial coinfections and thereby increase the severity of the disease., (Copyright © 2021 de Buhr and von Köckritz-Blickwede.)

Tuberculosis (TB) is the leading cause of death among HIV-1-infected individuals and Mycobacterium tuberculosis ( Mtb ) co-infection is an early precipitate to AIDS. We aimed to determine whether Mtb strains differentially modulate cellular susceptibility to HIV-1 infection ( cis - and trans -infection), via surface receptor interaction by their cell envelope lipids. Total lipids from pathogenic (lineage 4 Mtb H37Rv, CDC1551 and lineage 2 Mtb HN878, EU127) and non-pathogenic ( Mycobacterium bovis BCG and Mycobacterium smegmatis ) Mycobacterium strains were integrated into liposomes mimicking the lipid distribution and antigen accessibility of the mycobacterial cell wall. The resulting liposomes were tested for modulating in vitro HIV-1 cis - and trans -infection of TZM-bl cells using single-cycle infectious virus particles. Mtb glycolipids did not affect HIV-1 direct infection however, trans -infection of both R5 and X4 tropic HIV-1 strains were impaired in the presence of glycolipids from M. bovis , Mtb H37Rv and Mtb EU127 strains when using Raji-DC-SIGN cells or immature and mature dendritic cells (DCs) to capture virus. SL1, PDIM and TDM lipids were identified to be involved in DC-SIGN recognition and impairment of HIV-1 trans -infection. These findings indicate that variant strains of Mtb have differential effect on HIV-1 trans -infection with the potential to influence HIV-1 disease course in co-infected individuals.

Opportunistic bacterial infections amongst HIV-infected individuals contribute significantly to HIV-associated mortality. The role of HIV-mediated modulation of innate mechanisms like autophagy in promoting opportunistic infections, however, remains obscure. Here we show, HIV reactivation in or infection of macrophages inhibits autophagy and helps the survival of pathogenic Mycobacterium tuberculosis (Mtb) and nonpathogenic non-tuberculous mycobacterial strains (NTMs). The HIV-mediated impairment of xenophagy flux facilitated bacterial survival. Activation of autophagy by trehalose could induce xenophagy flux and kill intracellular Mtb or NTMs either during single or co-infections. Trehalose, we delineate, activates PIKFYVE leading to TFEB nuclear translocation in MCOLN1-dependent manner to induce autophagy. Remarkably, trehalose significantly reduced HIV-p24 levels in ex-vivo -infected PBMCs or PBMCs from treatment-naive HIV patients and also controlled mycobacterial survival within Mtb -infected animals. To conclude, we report leveraging of HIV-mediated perturbed host innate-immunity by opportunistic bacterial pathogens and show an attractive therapeutic strategy for HIV and associated co-morbidities. Abbreviations: AIDS: acquired immune deficiency syndrome; AMPK: AMP-activated protein kinase; ATG5: autophagy related 5; BafA1: bafilomycin A 1 ; CFU: colony forming unit; CTSD: cathepsin D; CD63: CD63 molecule; EGFP: enhanced green fluorescent protein; FRET: Förster resonance energy transfer; GABARAP: gamma-aminobutyric acid receptor-associated protein; GAPDH: glyceraldehyde 3-phosphate dehydrogenase; GLUT: glucose transporter; HIV: human immunodeficiency virus; hMDMs: human monocyte derived macrophages; IL2: interleukin 2; LAMP1: lysosomal-associated membrane protein 1; LC3B-II: lipidated microtubule-associated proteins 1A/1B light chain 3B; Mtb: Mycobacterium tuberculosis ; MTOR: mechanistic target of rapamycin; mRFP: monomeric red fluorescent protein; M6PR: mannose-6-phosphate receptor; NAC: N- acetyl- L -cysteine; NTM's: non-tuberculous mycobacteria; PBMC: Peripheral Blood Mononuclear cells; PIKFYVE: phosphoinositide kinase; FYVE-Type Zinc Finger; PHA: phytohemagglutinin; PMA: phorbol 12-myristate 13-acetate; PtdIns(3,5)P2: Phosphatidylinositol 3,5-bisphosphate; ptfLC3: pEGFP-mRFP-LC3 ; ROS: reactive oxygen species; SQSTM1: sequestosome1; TFEB: transcription factor EB; MCOLN1/TRPML1: mucolipin 1; PIP4P1/TMEM55B: Human trans-membrane Protein 55B; UVRAG: UV Radiation Resistance Associate; VPS35: vacuolar protein sorting associated protein 35; WDR45: WD repeat domain 45; YCAM: Yellow Chameleon.

Infections of the lung are among the leading causes of death worldwide. Despite the preactivation of innate defense programs during viral infection, secondary bacterial infection substantially elevates morbidity and mortality rates. Particularly problematic are co-infections with influenza A virus (IAV) and the major bacterial pathogen Streptococcus pneumoniae. However, the molecular processes underlying the severe course of such co-infections are not fully understood. Previously, the absence of secreted glycoprotein Chitinase-3-like 1 (CHI3L1) was shown to increase pneumococcal replication in mice. We therefore hypothesized that an IAV preinfection decreases CHI3L1 levels to promote pneumococcal infection. Indeed, in an air-liquid interface model of primary human bronchial epithelial cells (hBECs), IAV preinfection interfered with apical but not basolateral CHI3L1 release. Confocal time-lapse microscopy revealed that the gradual loss of apical CHI3L1 localization during co-infection with influenza and S. pneumoniae coincided with the disappearance of goblet as well as ciliated cells and increased S. pneumoniae replication. Importantly, extracellular restoration of CHI3L1 levels using recombinant protein significantly reduced bacterial load in influenza preinfected bronchial models. Thus, recombinant CHI3L1 may provide a novel therapeutic means to lower morbidity and mortality associated with post-influenza pneumococcal infections., (© 2020 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Porcine circovirus type 2 (PCV2) and Streptococcus suis serotype 2 (SS2) clinical coinfection cases have been frequently detected. The respiratory epithelium plays a crucial role in host defense against a variety of inhaled pathogens. Reactive oxygen species (ROS) are involved in killing of bacteria and host immune response. The aim of this study is to assess whether PCV2 and SS2 coinfection in swine tracheal epithelial cells (STEC) affects ROS production and investigate the roles of ROS in bacterial survival and the inflammatory response. Compared to SS2 infection, PCV2/SS2 coinfection inhibited the activity of NADPH oxidase, resulting in lower ROS levels. Bacterial intracellular survival experiments showed that coinfection with PCV2 and SS2 enhanced SS2 survival in STEC. Pretreatment of STEC with N-acetylcysteine (NAC) also helps SS2 intracellular survival, indicating that PCV2/SS2 coinfection enhances the survival of SS2 in STEC through a decrease in ROS production. In addition, compared to SS2-infected STEC, PCV2/SS2 coinfection and pretreatment of STEC with NAC prior to SS2 infection both downregulated the expression of the inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and IL-1β. Further research found that activation of p38/MAPK promoted the expression of inflammatory cytokines in SS2-infected STEC; however, PCV2/SS2 coinfection or NAC pretreatment of STEC inhibited p38 phosphorylation, suggesting that coinfection of STEC with PCV2 and SS2 weakens the inflammatory response to SS2 infection through reduced ROS production. Collectively, coinfection of STEC with PCV2 and SS2 enhances the intracellular survival of SS2 and weakens the inflammatory response through decreased ROS production, which might exacerbate SS2 infection in the host., (Copyright © 2020 American Society for Microbiology.)

Mycobacterium tuberculosis (Mtb) is a highly infectious acid-fast bacillus and is known to cause tuberculosis (TB) in humans. It is a leading cause of death from a sole infectious agent, with an estimated 1.5 million deaths yearly worldwide, and up to one third of the world's population has been infected with TB. The virulence and susceptibility of Mtb are further amplified in the presence of Human Immunodeficiency Virus (HIV). Coinfection with Mtb and HIV forms a lethal combination. Previous studies had demonstrated the synergistic effects of Mtb and HIV, with one disease accelerating the disease progression of the other through multiple mechanisms, including the modulation of the immune response to these two pathogens. The response of the endosomal pattern recognition receptors to these two pathogens, specifically toll-like receptors (TLR)-3, -7, and -9, has not been elucidated, with some studies producing mixed results. This article seeks to review the roles of TLR-3, -7, and -9 in response to Mtb infection, as well as Mtb-HIV-coinfection via Toll-interleukin 1 receptor (TIR) domain-containing adaptor inducing INF-β (TRIF)-dependent and myeloid differentiation factor 88 (MyD88)-dependent pathways.

Patients who survive sepsis display prolonged immune dysfunction and heightened risk of secondary infection. CD4 T cells support a variety of cells required for protective immunity, and perturbations to the CD4 T cell compartment can decrease overall immune system fitness. Using the cecal ligation and puncture (CLP) mouse model of sepsis, we investigated the impact of sepsis on endogenous Ag-specific memory CD4 T cells generated in C57BL/6 (B6) mice infected with attenuated Listeria monocytogenes (Lm) expressing the I-A b -restricted 2W1S epitope (Lm-2W). The number of 2W1S-specific memory CD4 T cells was significantly reduced on day 2 after sepsis induction, but recovered by day 14. In contrast to the transient numerical change, the 2W1S-specific memory CD4 T cells displayed prolonged functional impairment after sepsis, evidenced by a reduced recall response (proliferation and effector cytokine production) after restimulation with cognate Ag. To define the extent to which the observed functional impairments in the memory CD4 T cells impacts protection to secondary infection, B6 mice were infected with attenuated Salmonella enterica- 2W ( Se -2W) 30 days before sham or CLP surgery, and then challenged with virulent Se- 2W after surgery. Pathogen burden was significantly higher in the CLP-treated mice compared to shams. Similar reductions in functional capacity and protection were noted for the endogenous OVA 323 -specific memory CD4 T cell population in sepsis survivors upon Lm-OVA challenge. Our data collectively show CLP-induced sepsis alters the number and function of Ag-specific memory CD4 T cells, which contributes (in part) to the characteristic long-lasting immunoparalysis seen after sepsis., (Copyright © 2020 Sjaastad, Kucaba, Dileepan, Swanson, Dail, Cabrera-Perez, Murphy, Badovinac and Griffith.)

The Birnaviridae family, responsible for major economic losses to poultry and aquaculture, is composed of nonenveloped viruses with a segmented double-stranded RNA (dsRNA) genome that replicate in discrete cytoplasmic virus factories (VFs). Reassortment is common; however, the underlying mechanism remains unknown given that VFs may act as a barrier to genome mixing. In order to provide new information on VF trafficking during dsRNA virus coinfection, we rescued two recombinant infectious bursal disease viruses (IBDVs) of strain PBG98 containing either a split GFP11 or a tetracysteine (TC) tag fused to the VP1 polymerase (PBG98-VP1-GFP11 and PBG98-VP1-TC). DF-1 cells transfected with GFP1-10 prior to PBG98-VP1-GFP11 infection or stained with a biarsenical derivative of the red fluorophore resorufin (ReAsH) following PBG98-VP1-TC infection, had green or red foci in the cytoplasm, respectively, that colocalized with VP3 and dsRNA, consistent with VFs. The average number of VFs decreased from a mean of 60 to 5 per cell between 10 and 24 h postinfection (hpi) ( P < 0.0001), while the average area increased from 1.24 to 45.01 μm 2 ( P < 0.0001), and live cell imaging revealed that the VFs were highly dynamic structures that coalesced in the cytoplasm. Small VFs moved faster than large (average 0.57 μm/s at 16 hpi compared to 0.22 μm/s at 22 hpi), and VF coalescence was dependent on an intact microtubule network and actin cytoskeleton. During coinfection with PBG98-VP1-GFP11 and PBG98-VP1-TC viruses, discrete VFs initially formed from each input virus that subsequently coalesced 10 to 16 hpi, and we speculate that Birnaviridae reassortment requires VF coalescence. IMPORTANCE Reassortment is common in viruses with segmented double-stranded RNA (dsRNA) genomes. However, these viruses typically replicate within discrete cytoplasmic virus factories (VFs) that may represent a barrier to genome mixing. We generated the first replication competent tagged reporter birnaviruses, infectious bursal disease viruses (IBDVs) containing a split GFP11 or tetracysteine (TC) tag and used the viruses to track the location and movement of IBDV VFs, in order to better understand the intracellular dynamics of VFs during a coinfection. Discrete VFs initially formed from each virus that subsequently coalesced from 10 h postinfection. We hypothesize that VF coalescence is required for the reassortment of the Birnaviridae This study provides new information that adds to our understanding of dsRNA virus VF trafficking., (Copyright © 2020 Campbell et al.)

Acute lung injury is an inflammatory condition developed after severe sepsis in response to excessive secretion of pro-inflammatory cytokines. Doxycycline is widely reported to possess immunomodulatory activity through inhibition of various inflammatory pathways. Considering the broad spectrum of anti-inflammatory activity, protective effect of doxycycline was evaluated in clinically relevant murine polymicrobial sepsis model induced by caecal ligation and puncture (CLP). In this model, sepsis is accompanied with infection and therefore ceftriaxone at sub-protective dose was combined to retard the bacterial growth. Three hours after CLP challenge, mice were administered vehicle, ceftriaxone (100 mg/kg subcutaneously) alone and in combination with immunomodulatory dose of doxycycline (50 mg/kg, intraperitoneal) and survival were monitored for 5 days. Bacterial count in blood and peritoneal fluid along with cytokines [interleukin (IL)-6, IL-1β, tumour necrosis factor (TNF)-α] and myeloperoxidase (MPO) in plasma and lung homogenate were measured at 18 h post-CLP. Plasma glutathione (GSH) was also determined. Doxycycline in presence of ceftriaxone improved survival of septic mice by significantly reducing the plasma and lung pro-inflammatory cytokines and MPO levels. It also increased plasma GSH levels. Doxycycline did not improve antibacterial effect of ceftriaxone in combination, suggesting that the protective effect of doxycycline was due to its immunomodulatory activity. Doxycycline in the presence of ceftriaxone demonstrated improved survival of septic mice by modulating the immune response.

The use of reliable scores is a constant development in critical illness. According to Sepsis-3 consensus, the use of Sequential Organ Failure Assessment (SOFA) score of 2 or more is associated with a higher mortality of sepsis patients. In experimental research, due murine animal model limitations, the use of a score systems can be an alternative to assess sepsis severity. In this work, we suggest a sickness behavior score (SBS) that uses physiological variables to assess sepsis severity and mortality. Animals were evaluated daily by the presence of six indicators of sickness behavior: temperature alteration, preference of water/sucrose, liquid intake, food intake, body weight, and movimentation. Male adult Wistar rats were evaluated daily after sepsis induction by cecal ligation and puncture (CLP) or laparotomy only (sham) for determination of SBS. Oxidative stress, IL-6, and HPA axis markers (corticosterone and adrenal gland weight) were evaluated 24 h after CLP to determine the correlation with the acute SBS and neuroinflammation. Also, BDNF and four cognitive behavioral tests were correlated with the chronic SBS, i.e., sum of 8 days after surgery. In result, septic rats presented higher SBS than sham animals. Sepsis severity markers were associated with acute and chronic SBS. Also, SBS was negative correlated with the cognitive tests. In conclusion, SBS shows to be reliable score to predict sepsis severity and mortality. The use of score system provides the analysis of global sickness behavior, beyond evaluation of each parameter individually.

Aim: HPV is an important cause of cervical cancer, but Chlamydia trachomatis (CT) is suspiciously involved in this disease ranging from direct to its involvement as a cofactor with HPV. We performed this study to understand the interaction of HPV and C. trachomatis  with humans and its contribution to cervical cancer. Materials & methods: Host-pathogen and pathogen-pathogen protein-protein interaction maps of HPV/CT/human were prepared and compared to analyze interactions during single/coinfection of C. trachomatis and HPV. The interacting human proteins were detected by their involvement in cervical cancer. Results: C. trachomatis may interact with several cancer associated proteins while HPV and C. trachomatis  largely interact with different human proteins, suggesting different pathogenesis. Conclusion: C. trachomatis  coinfection with HPV may modulate cervical cancer development.

The liver is the main organ responsible for bacterial and endotoxin clearance. Pyroptosis is a form of proinflammatory programmed cell death activated by caspase-1/11 and gasdermin D (GadD). Pyroptosis protects the host against bacterial infection; however, overactive pyroptosis can lead to organ injury. Glutamine (GLN) is a specific amino acid with anti-inflammatory and immunomodulatory properties. This study investigated the effects of GLN pretreatment on liver pyroptosis in a mouse model of polymicrobial sepsis. Mice were assigned to sham, sepsis control (Sepsis-C), and sepsis GLN (Sepsis-G) groups. The sham and Sepsis-C groups were fed the AIN-93G diet. The Sepsis-G group was provided with identical diet components except that part of the casein was replaced by GLN. After feeding the respective diets for 2 weeks, a cecal ligation and puncture (CLP) procedure was performed in the sepsis groups. An antibiotic was administered after CLP. Mice were sacrificed at either 24 or 72 h after CLP. The results showed that sepsis resulted in upregulated liver caspase-1/11 expression. Compared to the Sepsis-C group, the Sepsis-G group had higher liver caspase-11 and NLRP3 gene expressions at 24 h and lower active caspase-1/11 and cleaved GadD protein levels at 72 h after sepsis. Additionally, liver inflammatory cytokine gene expressions had decreased by 72 h post-CLP. The findings suggest that prophylactic administration of GLN initially upregulated liver pyroptosis to eradicate pathogens, yet the process of pyroptosis was suppressed in the late phase of sepsis. This may have beneficially attenuated liver inflammation and injury in an antibiotic-treated septic condition., Competing Interests: the authors declare no conflict of interest.

Background: Though a few studies in animal models suggest that intestinal helminths (IH) favorably affect evolution of gastritis associated with Helicobacter pylori (H. pylori) the studies supporting this concept in humans are only a few and are based on serological data., Methods: To evaluate the possible influence of IH on the human gastric mucosa, three groups of Venezuelan adults with gastropathy (endoscopically diagnosed) were studied: H. pylori-/IH- (n = 17), H. pylori+/IH- (n = 18), and H. pylori+/IH+ (n = 11). Histological analysis (hematoxylin-eosin) and immunohistochemical staining (peroxidase) for cytokines interleukin-1beta (IL-1β), tumor necrosis factor alpha (TNF-α), gamma interferon (IFN-γ), and interleukin 4 (IL-4) were undertaken in gastric antral biopsies., Results: Expression of the four cytokines was detected in all individuals in varying degrees, but proinflammatory cytokines were expressed in a higher degree in the H. pylori+/IH- group, mainly IL-1β (Th1-dominant immune response), associated with a higher degree of both histological inflammation and gastric cancer risk index (GCRI), as compared to the H. pylori-/IH- group. In contrast, an increased expression of IL-4 and a reduced expression of proinflammatory cytokines (Th2-dominant response), plus the tendency to a lower degree of mononuclear infiltration, mucosal atrophy in gastric corpus, and GCRI, were evidenced in the coinfected group., Conclusions: The findings of the present study is perhaps the first histological evidence of a possible modulatory effect of IH on the gastric mucosal inflammatory response due to H. pylori infection in humans.

Background Human immunodeficiency virus (HIV) co-infection and chronic kidney disease add challenges to hepatitis C virus treatment. Objective To conduct a comparative study of treatment choices, drug-drug interactions and clinical outcomes in hepatitis C mono-infected patients, or those with HIV or chronic kidney disease comorbidities. Setting Hepatitis C treatment centers of West Midlands England, United Kingdom. Method An observational study was conducted analyzing datasets of all hepatitis C patients that were referred to a large tertiary liver unit in the West Midlands, UK between July 2015 and January 2018. Patients aged ≥ 18 years with diagnosis of hepatitis C alone or co-infected with HIV or comorbid with chronic kidney disease were eligible. Main outcome measures The treatment choices, relevant potential drug-drug interactions and sustained virologic response 12 weeks post end of treatment were assessed. Results Out of 313 patients, 154 (49.2%) were hepatitis C mono-infected, 124 (39.6%) hepatitis C/HIV co-infected and 35 (11.2%) were hepatitis C/chronic kidney disease comorbid. There were 151 (98.1%) of hepatitis C mono-infected, 110 (88.7%) of hepatitis C/HIV and 20 (57.1%) of hepatitis C/chronic kidney disease patients treated with 1st line regimens. Significantly more patients who had co-morbidity with either HIV or chronic kidney disease were prescribed 2nd line regimens (8.1% and 37.1% respectively), compared to patients with hepatitis C mono-infection (1.9%) (P value < 0.05). Comorbid patients (12.1% of HIV and 25.8% of chronic kidney disease) were more likely to required drug-drug interactions advice (grade 5) than hepatitis C mono-infected (1.8%). Higher cure rates were observed in hepatitis C mono-infected (95.33%), hepatitis C/HIV (96.1%) compared to hepatitis C/chronic kidney disease patients (90.3%). Conclusion This study shows that treatment pathways permitting access to individual treatment adjustments in accordance with comorbidities and with consideration of drug-drug interaction in a multi-disciplinary team, provides successful outcomes in hepatitis C patients co-morbid with HIV or chronic kidney disease.

Human co-infection by helminth species is frequent, but their consequences are mostly unknown. Here, we investigate the impact of Strongyloides venezuelensis co-infection on the immune response, schistosome burden, and the associated pathology of schistosomiasis in mice. Co-infection did not alter the schistosome parasite burden, but reduced the IL-4/IL-10 ratio during acute schistosomiasis, indicating induction of modulatory mechanisms. Simultaneous infection with S. venezuelensis and S. mansoni increased the liver concentration of IFN-γ and altered the Th2/Th1 balance, leading to great infiltration of neutrophils and macrophages, which resulted in larger liver inflammation and increased serum transaminase activity in comparison with mono-infected mice. Mice infected with S. venezuelensis at two and four weeks after S. mansoni infection showed significant increase of Th1/Th2/Th17/Treg cytokines and strong cellular infiltration in the liver in comparison with mono-infected mice. However, only in mice co-infected after two weeks of schistosomiasis, the liver immune response leads to more intense Th2 polarization, increased liver inflammation, and transaminase serum activity. S. venezuelensis co-infection during chronic schistosomiasis did not significantly alter liver inflammation. Therefore, S. venezuelensis co-infection affects the host immune responses and morbidity of schistosomiasis, but the effects largely depend on the stage of the S. mansoni infection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Individuals with impaired immune responses, such as ventilated and cystic fibrosis patients are often infected with Pseudomonas aeruginosa ( P.a ) bacteria, and a co-infection with the Influenza virus (IAV) is often present. It has been known for many years that infection with IAV predisposes the host to secondary bacterial infections (such as Streptococcus pneumoniae or Staphylococcus aureus ), and there is an abundance of mechanistic studies, including those studying the role of desensitization of TLR signaling, type I IFN- mediated impairment of neutrophil chemokines and antimicrobial production, attenuation of IL1β production etc., showing this. However, little is known about the mechanistic events underlying the potential deleterious synergy between Influenza and P.a co-infections. We demonstrate here in vitro in epithelial cells and in vivo in three independent models (two involving mice given IAV +/- P.a , and one involving mice given IAV +/- IL-1β) that IAV promotes secondary P.a -mediated lung disease or augmented IL-1β-mediated inflammation. We show that IAV- P.a -mediated deleterious responses includes increased matrix metalloprotease (MMP) activity, and MMP-9 in particular, and that the use of the MMP inhibitor improves lung resilience. Furthermore, we show that IAV post-transcriptionally inhibits the antimicrobial/anti-protease molecule elafin/trappin-2, which we have shown previously to be anti-inflammatory and to protect the host against maladaptive neutrophilic inflammation in P.a infections. Our work highlights the capacity of IAV to promote further P.a -mediated lung damage, not necessarily through its interference with host resistance to the bacterium, but by down-regulating tissue resilience to lung inflammation instead. Our study therefore suggests that restoring tissue resilience in clinical settings where IAV/ P.a co-exists could prove a fruitful strategy., (Copyright © 2020 Villeret, Solhonne, Straube, Lemaire, Cazes, Garcia-Verdugo and Sallenave.)

Despite intensive research and constant medical progress, sepsis remains one of the most urgent unmet medical needs of today. Most studies have been focused on the inflammatory component of the disease; however, recent advances support the notion that sepsis is accompanied by extensive metabolic perturbations. During times of limited caloric intake and high energy needs, the liver acts as the central metabolic hub in which PPARα is crucial to coordinate the breakdown of fatty acids. The role of hepatic PPARα in liver dysfunction during sepsis has hardly been explored. We demonstrate that sepsis leads to a starvation response that is hindered by the rapid decline of hepatic PPARα levels, causing excess free fatty acids, leading to lipotoxicity, and glycerol. In addition, treatment of mice with the PPARα agonist pemafibrate protects against bacterial sepsis by improving hepatic PPARα function, reducing lipotoxicity and tissue damage. Since lipolysis is also increased in sepsis patients and pemafibrate protects after the onset of sepsis, these findings may point toward new therapeutic leads in sepsis., (© 2020 The Authors. Published under the terms of the CC BY 4.0 license.)

Ivermectin is a widely used drug for the treatment of various neglected tropical diseases, such as lymphatic filariasis, onchocerciasis, and strongyloidiasis among others. Despite its excellent safety profile, there are few published studies of the use of ivermectin in children, pregnant and nursing women. In the present study, we report clinical data on ivermectin concentrations in breastmilk of a woman with Strongyloides stercoralis and HTLV-I coinfection. Ivermectin levels in breastmilk ranged from 1.4 to 20.8 ng/ml, with a mean of 9.26 ng/ml after a single dose of 200 µg/kg. We estimated the possible ivermectin exposure of the infant to be 1.1 µg/kg, 0.55% of the weight-adjusted percentage of the maternal dose. This value is largely under the threshold established by the World Health Organization for safe breastfeeding. Our results bolster previous findings on the secretion of ivermectin into breastmilk in healthy volunteers. The findings from this case study do not support exclusion of lactating women or interrupting lactation to accommodate it., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The impact of spleen tyrosine kinase (Syk) signaling might be prominent in lupus because (i) Syk is a shared downstream signaling molecule among circulating immune complex, LPS, and (1→3)-β-D-glucan (BG), and (ii) all of these factors are detectable in the serum of Fc gamma receptor IIb-deficient (FcgRIIb-/-) mice with sepsis. As a proof of concept study, we activated macrophages with BG combined with LPS (BG + LPS). We found that BG + LPS predominantly upregulated Syk expression and proinflammatory cytokines in FcgRIIb-/- macrophages compared with wild-type (WT) macrophages. Syk inhibition downregulated several inflammatory pathways in FcgRIIb-/- macrophages activated with BG + LPS, as determined by RNA sequencing analysis, suggesting the potential anti-inflammatory impact of Syk inhibitors in lupus. Indeed, administration of a Syk inhibitor prior to cecal ligation and puncture (CLP) sepsis in FcgRIIb-/- mice reduced baseline lupus-induced proinflammatory cytokines and attenuated sepsis severity as evaluated by mortality, organ injury, serum LPS, and post-sepsis serum cytokines. In conclusion, it was easier to induce Syk expression in FcgRIIb-/- macrophages than in WT macrophages. This might be because of the loss of inhibitory signaling, which might be responsible for prominent Syk abundance in the spleens of 40-week-old FcgRIIb-/- mice and the potent effect of Syk inhibitor in lupus mice compared with WT., (© 2020 The Author(s). Published by S. Karger AG, Basel.)

Due to their physiological and biological characteristics, numerous fungi are potentially emerging pathogens. Active dynamicity of fungal pathogens causes life-threatening infections annually impose high costs to the health systems. Although immune responses play crucial roles in controlling the fate of fungal infections, immunocompromised patients are at high risk with high mortality. Tuning the immune response against fungal infections might be an effective strategy for controlling and reducing the pathological damages. MicroRNAs (miRNAs) are known as the master regulators of immune response. These single-stranded tuners (18-23 bp non-coding RNAs) are endogenously expressed by all metazoan eukaryotes and have emerged as the master gene expression controllers of at least 30% human genes. In this review article, following the review of biology and physiology (biogenesis and mechanism of actions) of miRNAs and immune response against fungal infections, the interactions between them were scrutinised. In conclusion, miRNAs might be considered as one of the potential goals in immunotherapy for fungal infections. Undoubtedly, advanced studies in this field, further identifying of miRNA roles in governing the immune response, pave the way for inclusion of miRNA-related immunotherapeutic in the treatment of life-threatening fungal infections., (© 2019 Blackwell Verlag GmbH.)

The synergies between viral and bacterial infections are well established. Most studies have been focused on the indirect mechanisms underlying this phenomenon, including immune modulation and alterations to the mucosal structures that promote pathogen outgrowth. A growing body of evidence implicates direct binding of virus to bacterial surfaces being an additional mechanism of synergy at the host-pathogen interface. These cross-kingdom interactions enhance bacterial and viral adhesion and can alter tissue tropism. These bacterial-viral complexes play unique roles in pathogenesis and can alter virulence potential. The bacterial-viral complexes may also play important roles in pathogen transmission. Additionally, the complexes are recognized by the host immune system in a distinct manner, thus presenting novel routes for vaccine development. These synergies are active for multiple species in both the respiratory and gastrointestinal tract, indicating that direct interactions between bacteria and virus to modulate host interactions are used by a diverse array of species., (© 2019 WILEY Periodicals, Inc.)

In vivo bioluminescence imaging has been used to monitor Staphylococcus aureus infections in preclinical models by employing bacterial reporter strains possessing a modified lux operon from Photorhabdus luminescens. However, the relatively short emission wavelength of lux (peak 490 nm) has limited tissue penetration. To overcome this limitation, the gene for the click beetle (Pyrophorus plagiophtalamus) red luciferase (luc) (with a longer >600 emission wavelength), was introduced singly and in combination with the lux operon into a methicillin-resistant S. aureus strain. After administration of the substrate D-luciferin, the luc bioluminescent signal was substantially greater than the lux signal in vitro. The luc signal had enhanced tissue penetration and improved anatomical co-registration with infected internal organs compared with the lux signal in a mouse model of S. aureus bacteremia with a sensitivity of approximately 3 × 10 4 CFU from the kidneys. Finally, in an in vivo mixed bacterial wound infection mouse model, S. aureus luc signals could be spectrally unmixed from Pseudomonas aeruginosa lux signals to noninvasively monitor the bacterial burden of both strains. Therefore, the S. aureus luc reporter may provide a technological advance for monitoring invasive organ dissemination during S. aureus bacteremia and for studying bacterial dynamics during mixed infections.

Nevirapine-based antiretroviral therapy (ART) is one of the limited options in HIV-infected children younger than 3 years old (young children) with tuberculosis (TB) coinfection. To date, there are insufficient data to recommend nevirapine-based therapy during first-line antituberculosis (anti-TB) therapy in young children. We compared nevirapine pharmacokinetics (PK) in HIV-infected young children with and without TB coinfection. In the coinfected group, nevirapine PK was evaluated while on anti-TB therapy and after completing an anti-TB therapy regimen. Of 53 participants, 23 (43%) had TB-HIV coinfection. While the mean difference in nevirapine PK parameters between the two groups was not significant ( P  > 0.05), 14/23 (61%) of the children with TB-HIV coinfection and 9/30 (30%) with HIV infection had a nevirapine minimum concentration ( C min ) below the proposed target of 3.0 mg/liter ( P  = 0.03). In multivariate analysis, anti-TB therapy and the CYP2B6 516G>T genotype were joint predictors of nevirapine PK parameters. Differences in nevirapine PK parameters between the two groups were significant in children with CYP2B6 516GG but not the GT or TT genotype. Among 14 TB-HIV-coinfected participants with paired data, the geometric mean C min and area under the drug concentration-time curve from time zero to 12 h (AUC 0-12 ) were about 34% lower when patients were taking anti-TB therapy, while the nevirapine apparent oral clearance (CL/ F ) was about 45% higher. While the induction effect of anti-TB therapy on nevirapine PK in our study was modest, the CYP2B6 genotype-dependent variability in the TB drug regimen effect would complicate any dose adjustment strategy in young children with TB-HIV coinfection. Alternate ART regimens that are more compatible with TB treatment in this age group are needed. (This study has been registered at ClinicalTrials.gov under identifier NCT01699633.)., (Copyright © 2019 American Society for Microbiology.)

Aims: The present study investigated if berberine might induce Zrt-Irt-like protein 14 (ZIP14) and affect zinc redistribution to protect intestinal barrier in sepsis., Main Methods: Rodent model of sepsis was induced by cecal ligation and puncture (CLP). Plasma endotoxin was assayed by LAL test and plasma zinc was measured by flame atomic spectrophotometer. Gut mucosal permeability was determined by plasma FITC-dextran. Zinc content and ZIP14 mRNA in gut mucosa were assayed by spectrophotometer and qRT-PCR, respectively. Tight junction integrity of Caco-2 was evaluated by transepithelial electrical resistance (TEER). Tight junction (TJ) protein expression was detected by Western blotting., Key Findings: Berberine and zinc gluconate pretreatment to CLP rats improved survival rate, reduced plasma endotoxin level, alleviated hypozincemia, increased zinc accumulation and ZIP14 mRNA expression in the intestinal mucosa. Berberine and zinc gluconate pretreatment decreased CLP-elicited intestinal hyperpermeability to FITC-dextran. These effects of berberine in vivo were abolished by AG1024. In vitro, lipopolysaccharide (LPS) repressed zinc transfer into Caco-2 cells exposed to zinc gluconate. Berberine and IGF-I treatment increased ZIP14 protein expression and promoted zinc transfer into Caco-2 cells exposed to zinc gluconate plus LPS. Berberine treatment induced TJ protein (claudin-1 and occludin) and raised TEER in LPS-treated Caco-2 cells. These effects of berberine in vitro were partially inhibited by ZIP14 siRNA., Significance: The present study reveals that berberine induces ZIP14 expression and affects zinc re- distribution to protect intestinal barrier in sepsis, which is partially linked with the activation of IGF-I signaling., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Molecular diagnostic techniques have revealed that approximately 43% of the patients hospitalized with influenza-like illness are infected by more than one viral pathogen, sometimes leading to long-lasting infections. It is not clear how the heterologous viruses interact within the respiratory tract of the infected host to lengthen the duration of what are usually short, self-limiting infections. We develop a mathematical model which allows for single cells to be infected simultaneously with two different respiratory viruses (superinfection) to investigate the possibility of chronic coinfections. We find that a model with superinfection and cell regeneration has a stable chronic coinfection fixed point, while superinfection without cell regeneration produces only acute infections. This analysis suggests that both superinfection and cell regeneration are required to sustain chronic coinfection via this mechanism since coinfection is maintained by superinfected cells that allow slow-growing infections a chance to infect cells and continue replicating. This model provides a possible mechanism for chronic coinfection independent of any viral interactions via the immune response., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objectives: In resource-limited settings, mortality in the initial months following antiretroviral therapy (ART) initiation remains unacceptably high. Novel tools to identify patients at highest risk of poor outcomes are needed. We evaluated whether elevated C-reactive protein (CRP) concentrations predict poor outcomes among people living with HIV (PLWH) initiating ART., Methods: We enrolled and followed for 3-months consecutive PLWH with pre-ART CD4 T-cell counts 350 cells/μl or less initiating ART from two HIV clinics in Uganda. Pre-ART CRP concentrations were measured from capillary blood using a point-of-care (POC) assay. After excluding patients with prevalent tuberculosis - the leading cause of HIV death - we measured 3-month mortality rates using Kaplan-Meier curves, used Cox regression to compare differences in survival, and used logistic regression to compare differences in the odds of opportunistic infections, between patients with and without elevated POC CRP (≥8 mg/l)., Results: Of 1293 patients included [median CD4 T-cell count 181 (interquartile range 82-278)], 23 (1.8%) died within 3 months, including 19 of 355 (5.4%) with elevated POC CRP and four of 938 (0.4%) with nonelevated POC CRP. Eighty-six (6.7%) patients were diagnosed with opportunistic infections, including 39 of 355 (11.0%) with elevated POC CRP and 47 of 938 (5.0%) with nonelevated POC CRP. Elevated POC CRP was associated with mortality (adjusted hazard ratio 10.87, 95% confidence interval 3.64-32.47) and opportunistic infection (adjusted odds ratio 1.95, 95% confidence interval 1.23-3.07)., Conclusion: Among PLWH with advanced HIV, elevated pre-ART POC CRP concentrations are associated with early mortality and opportunistic infections. Pre-ART POC CRP testing may reduce mortality by identifying patients at high risk for poor outcomes.

Objectives. Viral bronchiolitis is a frequent cause of pediatric hospitalization and respiratory failure. Procalcitonin (PCT) is a biomarker used to identify serious bacterial infection and can distinguish bacterial and viral infections. Concomitant bacterial pneumonia is not rare in viral bronchiolitis and can lead to a worse clinical course. This study examined the use of PCT in pediatric patients with respiratory failure attributed to viral bronchiolitis to predict concomitant bacterial pneumonia. Methods. This prospective descriptive study evaluated children less than 4 years of age who underwent endotracheal intubation for respiratory failure due to viral bronchiolitis. PCT levels and endotracheal aspirate cultures were obtained at admission. Bacterial pneumonia was defined as at least moderate growth of a single pathogenic organism from endotracheal culture. PCT levels were evaluated in groups with and without concomitant bacterial pneumonia. Results. Thirty-five patients were enrolled between February 2013 and May 2015. All subjects tested positive for at least 1 viral pathogen by nasal wash polymerase chain reaction or enzyme immunoassay. The top viruses obtained were respiratory syncytial virus (n = 15, 42.8%) and rhinovirus (n = 8, 22.9%). The incidence of bacterial pneumonia was 60% (21/35). The PCT median was 0.93 ng/mL (interquartile range = 0.25-6.64) in the bacterial pneumonia group and 1.85 ng/mL (interquartile range = 0.28-7.94) in the nonbacterial pneumonia group. No correlation was found between PCT and bronchiolitis with bacterial coinfection ( P = .74). Conclusion. Incidence of bacterial coinfection in patients with respiratory failure and viral bronchiolitis was high. PCT did not predict concomitant bacterial pneumonia in children with viral bronchiolitis.