Search

Background and Purpose: Benzoxathiolone derivatives have shown anti-inflammatory and immunomodulatory potential in acne and psoriatic disorders. However, little is known about the molecular basis for these pharmacological effects. In this study, we decided to investigate the anti-inflammatory actions of a benzoxathiolone derivative LYR-71, 6-methyl-2-propylimino-6,7-dihydro-5H-benzo[1,3]oxathiol-4-one, in interferon (IFN)-gamma-activated macrophages.Experimental Approach: RAW 264.7 macrophages or primary macrophages, derived from bone marrow of C3H/HeJ mice, were stimulated with IFN-gamma in the presence of LYR-71. Nitric oxide (NO) or chemokine production was measured by Griess reaction or enzyme-linked immunosorbent assay. RAW 264.7 cells were used to examine the molecular mechanisms of LYR-71 in modulating IFN-gamma-induced inflammatory responses.Key Results: LYR-71 down-regulated IFN-gamma-induced transcription of inducible NO synthase, IFN-gamma-inducible protein-10 and the monokine induced by IFN-gamma genes in macrophages. This effect was mediated by uncoupling tyrosine phosphorylation of the signal transducer and activator of transcription (STAT)-1 in response to IFN-gamma. LYR-71 directly inhibited the in vitro catalytic activity of Janus kinase (JAK)-2. Further, the inhibitory actions of LYR-71 on IFN-gamma-induced STAT-1 phosphorylation and NO production were consistently abolished in the presence of peroxyvanadate, implying another target dependent on protein tyrosine phosphatase.Conclusions and Implications: Taken together, LYR-71 could restrain IFN-gamma-induced inflammatory responses through uncoupling the tyrosine phosphorylation of STAT-1, an activation index of JAK-STAT-1 signalling, in macrophages. These results may provide a molecular mechanism underlying anti-inflammatory actions shown by benzoxathiolone derivatives. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate interferon-gamma (IFNgamma) signaling in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE) by analyzing IFNgamma receptor (IFNgammaR) expression, STAT-1 expression and phosphorylation, and the regulation of IFNgamma-inducible genes. METHODS: Fluorocytometry was used to investigate expression of STAT-1, pSTAT-1, CD95, HLA-DR, class I major histocompatibility complex (MHC), IFNgamma-inducible 10-kd protein (IP-10), monokine induced by IFNgamma (Mig), and IFNgammaR in PBMCs from SLE patients and healthy individuals. STAT-1 phosphorylation was determined by fluorocytometry and Western blotting after stimulation with IFNalpha or IFNgamma. Quantitative polymerase chain reaction was used to assess messenger RNA (mRNA) expression of the IFNgamma-inducible genes IP-10 and Mig shortly after preparation or after stimulation with IFNgamma in monocytes. RESULTS: STAT-1 expression was increased in PBMCs from SLE patients and correlated significantly with disease activity and with the IFN-inducible expression of CD95 and HLA-DR. STAT-1 expression also showed a trend toward association with class I MHC expression. In addition, the expression of other IFNgamma-inducible genes, such as IP-10 or Mig, was increased in SLE monocytes. While STAT-1 phosphorylation in SLE PBMCs and PBMCs from healthy individuals was similar after IFNalpha stimulation, incubation with IFNgamma induced STAT-1 phosphorylation only in SLE lymphocytes. Moreover, SLE monocytes showed a considerably higher increase in pSTAT-1 expression upon IFNgamma stimulation than monocytes from healthy individuals. Increased responsiveness of SLE monocytes to IFNgamma was also confirmed on the mRNA level, where expression of the IFN-inducible, STAT-1-dependent genes IP-10 and Mig was more efficiently increased in SLE cells. However, IFNgammaR was similarly expressed on SLE lymphocytes and monocytes and those from healthy individuals. CONCLUSION: In addition to supporting the role of IFNs in SLE immunopathogenesis in general, the findings of the present study support a role of IFNgamma in this disease. [ABSTRACT FROM AUTHOR]

Mononuclear cell infiltration of the salivary glands is a major feature of Sjögren''s syndrome (SS) and its animal model. Local generation of chemokines and the presence of chemokine receptors on the infiltrating cells may be involved in this process. We undertook the present study to investigate the expression of chemokines during the development of autoimmune sialadenitis in MRL/lpr mice and the therapeutic effect of chemokine antagonists on sialadenitis.NH2‐terminal–truncated interferon‐inducible protein 10 (IP‐10)/CXCL10 analogs were transfected into a nonmetastatic fibroblastoid cell line, MRL/N‐1, and injected subcutaneously into MRL/lpr mice, and the effects on sialadenitis were monitored.IP‐10 analogs truncated by 5 or more amino acid residues from the N‐terminal failed to induce chemotaxis and calcium influx by CXCR3‐expressing cells. Of these, the most potent antagonist (AT) (IP‐10–AT) was a molecule with methionine added after removal of the 5 N‐terminal amino acid residues. Significantly increased expression of the Th1‐associated chemokines IP‐10, monokine induced by interferon‐γ/CXCL9, and interferon‐inducible T cell chemoattractant/CXCL11 was induced in the ductal epithelium by interferon‐γ produced in the salivary glands, whereas expression of the Th2‐associated chemokines thymus and activation–regulated chemokine (TARC)/CCL17 and monocyte‐derived chemokine/CCL22 was almost undetectable during sialadenitis. Inoculation of IP‐10–AT into MRL/lpr mice during the early stage of sialadenitis significantly reduced periductal mononuclear cell infiltration and parenchymal destruction compared with these features in control and TARC‐AT–bearing mice. This was due to a significant reduction in infiltration of CXCR3+ T cells, predominantly Th1 cells, resulting in decreased interferon‐γ production.We prepared a novel potent IP‐10 antagonist and demonstrated its ability to ameliorate the progression of autoimmune sialadenitis. This agent may provide a new therapeutic approach to SS. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Mononuclear cell infiltration of the salivary glands is a major feature of Sjögren's syndrome (SS) and its animal model. Local generation of chemokines and the presence of chemokine receptors on the infiltrating cells may be involved in this process. We undertook the present study to investigate the expression of chemokines during the development of autoimmune sialadenitis in MRL/lpr mice and the therapeutic effect of chemokine antagonists on sialadenitis. METHODS: NH2-terminal-truncated interferon-inducible protein 10 (IP-10)/CXCL10 analogs were transfected into a nonmetastatic fibroblastoid cell line, MRL/N-1, and injected subcutaneously into MRL/lpr mice, and the effects on sialadenitis were monitored. RESULTS: IP-10 analogs truncated by 5 or more amino acid residues from the N-terminal failed to induce chemotaxis and calcium influx by CXCR3-expressing cells. Of these, the most potent antagonist (AT) (IP-10-AT) was a molecule with methionine added after removal of the 5 N-terminal amino acid residues. Significantly increased expression of the Th1-associated chemokines IP-10, monokine induced by interferon-gamma/CXCL9, and interferon-inducible T cell chemoattractant/CXCL11 was induced in the ductal epithelium by interferon-gamma produced in the salivary glands, whereas expression of the Th2-associated chemokines thymus and activation-regulated chemokine (TARC)/CCL17 and monocyte-derived chemokine/CCL22 was almost undetectable during sialadenitis. Inoculation of IP-10-AT into MRL/lpr mice during the early stage of sialadenitis significantly reduced periductal mononuclear cell infiltration and parenchymal destruction compared with these features in control and TARC-AT-bearing mice. This was due to a significant reduction in infiltration of CXCR3+ T cells, predominantly Th1 cells, resulting in decreased interferon-gamma production. CONCLUSION: We prepared a novel potent IP-10 antagonist and demonstrated its ability to ameliorate the progression of autoimmune sialadenitis. This agent may provide a new therapeutic approach to SS. [ABSTRACT FROM AUTHOR]

The close cooperation of both innate and acquired immunity is essential for the induction of truly effective antitumor immunity. We tested a strategy to enhance the cross-talk between NKT cells and conventional antigen-specific T cells with the use of αGalCer-loaded dendritic cells genetically engineered to express antigen plus chemokine, attracting both conventional T cells and NKT cells. DC genetically engineered to express a model antigen, OVA, along with SLC/CCL21 or monokine induced by IFN-γ/CXCL9, had been generated using a method based on in vitro differentiation of DC from mouse ES cells. The ES-DC were loaded with α-GalCer and transferred to mice bearing MO4, an OVA-expressing melanoma, and their capacity to evoke antitumor immunity was evaluated. In vivo transfer of either OVA-expressing ES-DC, stimulating OVA-reactive T cells, or α-GalCer-loaded non-transfectant ES-DC, stimulating NKT cells, elicited a significant but limited degree of protection against the i.p. disseminated MO4. A more potent antitumor effect was observed when α-GalCer was loaded to ES-DC expressing OVA before in vivo transfer, and the effect was abrogated by the administration of anti-CD8, anti-NK1.1 or anti-asialo GM1 antibody. α-GalCer-loaded double transfectant ES-DC expressing SLC along with OVA induced the most potent antitumor immunity. Thus, α-GalCer-loaded ES-DC expressing tumor-associated antigen along with SLC can stimulate multiple subsets of effector cells to induce a potent therapeutic effect against peritoneally disseminated tumor cells. The present study suggests a novel way to use α-GalCer in immunotherapy for peritoneally disseminated cancer. ( Cancer Sci 2005; 96: 889–896) [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the relationship between the vasculopathy of juvenile dermatomyositis (juvenile DM) and the balance between the angiostatic ELR- and angiogenic ELR+ CXC chemokines in the muscle of patients with the disease. METHODS: The expression of 3 ELR- CXC chemokines (interferon-inducible protein 10 [IP-10], monokine induced by interferon-gamma, and interferon-inducible T cell alpha-chemoattractant) and 2 ELR+ CXC chemokines was quantitated in muscle biopsy samples from 7 patients with juvenile DM and 7 healthy children, by real-time polymerase chain reaction. The findings were correlated with various histopathologic features, with particular emphasis on the degree of vasculopathy. Synovial biopsy specimens from patients with juvenile rheumatoid arthritis (JRA) were used for additional comparison. RESULTS: The angiostatic ELR- chemokines were expressed at high levels, while the angiogenic ELR+ chemokines were barely detectable, in most juvenile DM samples. This contrasted sharply with the findings in both normal muscle biopsy specimens and JRA synovial tissue specimens. The expression of the ELR- chemokines in juvenile DM samples correlated with the intensity of mononuclear cell infiltration. Furthermore, the juvenile DM samples with the highest degree of capillary loss had the highest levels of ELR- CXC chemokines. The presence of IP-10 in juvenile DM muscle specimens was confirmed by immunohistochemistry analysis. In addition, immunohistochemical staining of muscle tissue revealed that CXCR3, a receptor utilized by ELR- CXC chemokines, was expressed in vascular endothelial cells. CONCLUSION: Increased expression of the interferon-induced angiostatic ELR- CXC chemokines is a feature of juvenile DM that parallels the degree of vasculopathy in patients with the disease. Collectively, these findings are consistent with a model in which a subset of inflammatory cells secrete angiostatic ligands, which then contribute to a local atrophying effect on the muscle's vasculature via a receptor-mediated process. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the activation and recruitment pathways of relevant leukocyte subsets during the initiation and amplification of cutaneous lupus erythematosus (LE). METHODS: Quantitative real-time polymerase chain reaction was used to perform a comprehensive analysis of all known chemokines and their receptors in cutaneous LE lesions, and the cellular origin of these chemokines and receptors was determined using immunohistochemistry. Furthermore, cytokine- and ultraviolet (UV) light-mediated activation pathways of relevant chemokines were investigated in vitro and in vivo. RESULTS: In the present study, we identified the CXCR3 ligands CXCL9 (interferon-gamma [IFNgamma]-induced monokine), CXCL10 (IFNgamma-inducible protein 10), and CXCL11 (IFN-inducible T cell alpha chemoattractant) as being the most abundantly expressed chemokine family members in cutaneous LE. Expression of these ligands corresponded with the presence of a marked inflammatory infiltrate consisting of mainly CXCR3-expressing cells, including skin-homing lymphocytes and blood dendritic cell antigen 2-positive plasmacytoid dendritic cells (PDCs). Within cutaneous LE lesions, PDCs accumulated within the dermis and were activated to produce type I IFN, as detected by the expression of the IFNalpha-inducible genes IRF7 and MxA. IFNalpha, in turn, was a potent and rapid inducer of CXCR3 ligands in cellular constituents of the skin. Furthermore, we demonstrated that the inflammatory CXCR3 ligands cooperate with the homeostatic chemokine CXCL12 (stromal cell-derived factor 1) during the recruitment of pathogenically relevant leukocyte subsets. Moreover, we showed that UVB irradiation induces the release of CCL27 (cutaneous T cell-attracting chemokine) from epidermal compartments into dermal compartments and up-regulates the expression of a distinct set of chemokines in keratinocytes. CONCLUSION: Taken together, our data suggest an amplification cycle in which UV light-induced injury induces apoptosis, necrosis, and chemokine production. These mechanisms, in turn, mediate the recruitment and activation of autoimmune T cells and IFNalpha-producing PDCs, which subsequently release more effector cytokines, thus amplifying chemokine production and leukocyte recruitment, finally leading to the development of a cutaneous LE phenotype. [ABSTRACT FROM AUTHOR]

To investigate the activation and recruitment pathways of relevant leukocyte subsets during the initiation and amplification of cutaneous lupus erythematosus (LE).Quantitative real‐time polymerase chain reaction was used to perform a comprehensive analysis of all known chemokines and their receptors in cutaneous LE lesions, and the cellular origin of these chemokines and receptors was determined using immunohistochemistry. Furthermore, cytokine‐ and ultraviolet (UV) light–mediated activation pathways of relevant chemokines were investigated in vitro and in vivo.In the present study, we identified the CXCR3 ligands CXCL9 (interferon‐γ [IFNγ]–induced monokine), CXCL10 (IFNγ‐inducible protein 10), and CXCL11 (IFN‐inducible T cell α chemoattractant) as being the most abundantly expressed chemokine family members in cutaneous LE. Expression of these ligands corresponded with the presence of a marked inflammatory infiltrate consisting of mainly CXCR3‐expressing cells, including skin‐homing lymphocytes and blood dendritic cell antigen 2–positive plasmacytoid dendritic cells (PDCs). Within cutaneous LE lesions, PDCs accumulated within the dermis and were activated to produce type I IFN, as detected by the expression of the IFNα‐inducible genes IRF7 and MxA. IFNα, in turn, was a potent and rapid inducer of CXCR3 ligands in cellular constituents of the skin. Furthermore, we demonstrated that the inflammatory CXCR3 ligands cooperate with the homeostatic chemokine CXCL12 (stromal cell–derived factor 1) during the recruitment of pathogenically relevant leukocyte subsets. Moreover, we showed that UVB irradiation induces the release of CCL27 (cutaneous T cell–attracting chemokine) from epidermal compartments into dermal compartments and up‐regulates the expression of a distinct set of chemokines in keratinocytes. Taken together, our data suggest an amplification cycle in which UV light–induced injury induces apoptosis, necrosis, and chemokine production. These mechanisms, in turn, mediate the recruitment and activation of autoimmune T cells and IFNα‐producing PDCs, which subsequently release more effector cytokines, thus amplifying chemokine production and leukocyte recruitment, finally leading to the development of a cutaneous LE phenotype. [ABSTRACT FROM AUTHOR]

A population of neutrophils recruited into cystic fibrosis (CF) airways is associated with proteolytic lung damage, exhibiting high expression of primary granule exocytosis marker CD63 and reduced phagocytic receptor CD16. Causative factors for this population are unknown, limiting intervention. Here we present a laboratory model to characterize responses of differentiated airway epithelium and neutrophils following respiratory infection. Pediatric primary airway epithelial cells were cultured at the air–liquid interface, challenged individually or in combination with rhinovirus (RV) and Pseudomonas aeruginosa, then apically washed with medical saline to sample epithelial infection milieus. Cytokine multiplex analysis revealed epithelial antiviral signals, including IP‐10 and RANTES, increased with exclusive RV infection but were diminished if P. aeruginosa was also present. Proinflammatory signals interleukin‐1α and β were dominant in P. aeruginosa infection milieus. Infection washes were also applied to a published model of neutrophil transmigration into the airways. Neutrophils migrating into bacterial and viral–bacterial co‐infection milieus exhibited the in vivo CF phenotype of increased CD63 expression and reduced CD16 expression, while neutrophils migrating into milieus of RV‐infected or uninfected cultures did not. Individually, bacterial products lipopolysaccharide and N‐formylmethionyl‐leucyl‐phenylalanine and isolated cytokine signals only partially activated this phenotype, suggesting that additional soluble factors in the infection microenvironment trigger primary granule release. Findings identify P. aeruginosa as a trigger of acute airway inflammation and neutrophil primary granule exocytosis, underscoring potential roles of airway microbes in prompting this neutrophil subset. Further studies are required to characterize microbes implicated in primary granule release, and identify potential therapeutic targets. [ABSTRACT FROM AUTHOR]

The chemokine receptor CXCR3 is expressed on immune cells to co‐ordinate lymphocyte activation and migration. CXCR3 binds three chemokine ligands, CXCL9, CXCL10 and CXCL11. These ligands display distinct expression patterns and ligand signaling biases; however, how each ligand functions individually and collaboratively is incompletely understood. CXCL9 and CXCL10 are considered pro‐inflammatory chemokines during viral infection, while CXCL11 may induce a tolerizing state. The investigation of the individual role of CXCL11 in vivo has been hampered as C57BL/6 mice carry several mutations that result in a null allele. Here, CRISPR/Cas9 was used to correct these mutations on a C57BL/6 background. It was validated that CXCL11KI mice expressed CXCL11 protein in dendritic cells, spleen and lung. CXCL11KI mice were largely phenotypically indistinguishable from C57BL/6 mice, both at steady‐state and during two models of viral infection. While CXCL11 expression did not modify acute antiviral responses, this study provides a new tool to understand the role of CXCL11 in other experimental settings. [ABSTRACT FROM AUTHOR]

Background and Aim: Gut dysbiosis is associated with immune dysfunction and severity of COVID‐19. Whether targeting dysbiosis will improve outcomes of COVID‐19 is unknown. This study aimed to assess the effects of a novel gut microbiota‐derived synbiotic formula (SIM01) as an adjuvant therapy on immunological responses and changes in gut microbiota of hospitalized COVID‐19 patients. Methods: This was an open‐label, proof‐of‐concept study. Consecutive COVID‐19 patients admitted to an infectious disease referral center in Hong Kong were given a novel formula of Bifidobacteria strains, galactooligosaccharides, xylooligosaccharide, and resistant dextrin (SIM01). The latter was derived from metagenomic databases of COVID‐19 patients and healthy population. COVID‐19 patients who were admitted under another independent infectious disease team during the same period without receiving SIM01 acted as controls. All patients received standard treatments for COVID‐19 according to the hospital protocol. We assessed antibody response, plasma proinflammatory markers, nasopharyngeal SARS‐CoV‐2 viral load, and fecal microbiota profile from admission up to week 5. Results: Twenty‐five consecutive COVID‐19 patients received SIM01 for 28 days; 30 patients who did not receive the formula acted as controls. Significantly more patients receiving SIM01 than controls developed SARS‐CoV‐2 IgG antibody (88% vs 63.3%; P = 0.037) by Day 16. One (4%) and 8 patients (26.7%) in the SIM01 and control group, respectively, failed to develop positive IgG antibody upon discharge. At week 5, plasma levels of interleukin (IL)‐6, monocyte chemoattractant protein‐1 (MCP‐1), macrophage colony‐stimulating factor (M‐CSF), tumor necrosis factor (TNF‐α), and IL‐1RA reduced significantly in the SIM01 but not in the control group. There was a significant negative correlation of nasopharyngeal SARS‐CoV‐2 viral load and SIM01 intervention. Metagenomic analysis showed that bacterial species in SIM01 formula were found in greater abundance leading to enrichment of commensal bacteria and suppression of opportunistic pathogens in COVID‐19 patients by week 4 and week 5. Conclusions: This proof‐of‐concept study suggested that the use of a novel gut microbiota‐derived synbiotic formula, SIM01, hastened antibody formation against SARS‐CoV‐2, reduced nasopharyngeal viral load, reduced pro‐inflammatory immune markers, and restored gut dysbiosis in hospitalised COVID‐19 patients. [ABSTRACT FROM AUTHOR]

Chronic lung allograft dysfunction (CLAD) remains the major barrier to long‐term survival after lung transplantation and improved insight into its underlying immunological mechanisms is critical to better understand the disease and to identify treatment targets. We systematically searched the electronic databases of PubMed and EMBASE for original research publications, published between January 2000 and April 2021, to comprehensively assess current evidence on effector immune cells in lung tissue and bronchoalveolar lavage fluid from lung transplant recipients with CLAD. Literature search revealed 1351 articles, 76 of which met the criteria for inclusion in our analysis. Our results illustrate significant complexity in both innate and adaptive immune cell responses in CLAD, along with presence of numerous immune cell products, including cytokines, chemokines and proteases associated with tissue remodelling. A clear link between neutrophils and eosinophils and CLAD incidence has been seen, in which eosinophils more specifically predisposed to restrictive allograft syndrome. The presence of cytotoxic and T‐helper cells in CLAD pathogenesis is well‐documented, although it is challenging to draw conclusions about their role in tissue processes from predominantly bronchoalveolar lavage data. In restrictive allograft syndrome, a more prominent humoral immune involvement with increased B cells, immunoglobulins and complement deposition is seen. Our evaluation of published studies over the last 20 years summarizes the complex multifactorial immunopathology of CLAD onset and progression. It highlights the phenotype of several key effector immune cells involved in CLAD pathogenesis, as well as the paucity of single cell resolution spatial studies in lung tissue from patients with CLAD. [ABSTRACT FROM AUTHOR]

Bacterial pneumonia is one of the most important causes of mortality in the United States. The bacteria Klebsiella pneumoniae (KP) accounts for a significant proportion of community and hospital‐acquired infections. Here, we determine that the holy basil (Ocimum sanctum) extract improves cell viability and dampens the proinflammatory cytokine response in an in vitro model of pneumonia. For this, A549, a human alveolar basal epithelial cell line, was subjected to a lethal KP model following a 24‐hr pretreatment with basil extract. Bacteremia, cell viability, apoptosis, MTT assay, phagocytic capacity, cytokines, and Khe gene expression were assessed in these cells following pneumonia. Cell morphology analysis showed that holy basil protected A549 cells from KP infection–mediated effects by inhibiting cell death due to apoptosis. Additionally, in the presence of basil, A549 cells demonstrated significantly higher bactericidal capacity and phagocytosis. Administration of holy basil led to reduced expression of hypoxia‐inducible factor‐1/2a, nuclear factor kappa B, and Khe in the KP‐infected cells while increasing interferon (IFN)‐γ expression. Our results suggest that basil significantly reduced cell death in the setting of KP infection, likely via attenuation of cytokine and IFN‐γ mediated signaling pathways. Holy basil is a promising therapeutic agent for managing and treating bacterial pneumonia based on its potency. [ABSTRACT FROM AUTHOR]

This advanced review describes the anatomical and physiological barriers and mechanisms impacting nanomedicine translocation from the nasal cavity directly to the brain. There are significant physiological and anatomical differences in the nasal cavity, olfactory area, and airflow reaching the olfactory epithelium between humans and experimentally studied species that should be considered when extrapolating experimental results to humans. Mucus, transporters, and tight junction proteins present barriers to material translocation across the olfactory epithelium. Uptake of nanoparticles through the olfactory mucosa and translocation to the brain can be intracellular via cranial nerves (intraneuronal) or other cells of the olfactory epithelium, or extracellular along cranial nerve pathways (perineural) and surrounding blood vessels (perivascular, the glymphatic system). Transport rates vary greatly among the nose to brain pathways. Nanomedicine physicochemical properties (size, surface charge, surface coating, and particle stability) can affect uptake efficiency, which is usually less than 5%. Incorporation of therapeutic agents in nanoparticles has been shown to produce pharmacokinetic and pharmacodynamic benefits. Assessment of adverse effects has included olfactory mucosa toxicity, ciliotoxicity, and olfactory bulb and brain neurotoxicity. The results have generally suggested the investigated nanomedicines do not present significant toxicity. Research needs to advance the understanding of nanomedicine translocation and its drug cargo after intranasal administration is presented. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological DiseaseTherapeutic Approaches and Drug Discovery > Emerging TechnologiesToxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), an emerging virus in late 2019 causing coronavirus disease 2019 (COVID‐19), has caused a catastrophic effect, resulting in an unprecedented global crisis. The immunopathology of COVID‐19 appears to be clearly associated with a dysregulated immune response leading to organ failure and death. Similarly, over two billion people worldwide are infected with helminth, with those living in low‐middle‐income countries disproportionately affected. Helminth infections have been shown to possess immunomodulatory effects in several conditions. Helminth co‐infection in COVID‐19 patients is one of the potential reasons for global attention to answer why COVID‐19 severity is still lower in helminth endemic countries. Recent studies have shown that helminth endemic countries showed fewer cases and deaths so far and helminth co‐infection might reduce the severity of COVID‐19. Moreover, lessons from other diseases with helminth co‐infection have been shown to substantially reduce vaccine efficacy that could also be implicated for COVID‐19. This immunomodulatory effect of helminth has intended and unintended consequences, both advantageous and disadvantageous which could decrease the severity of COVID‐19 and COVID‐19 vaccine efficacy respectively. Herewith, we discuss the overview of COVID‐19 immune response, immunomodulatory effects of helminth co‐infections in COVID‐19, lessons from other diseases, and perspectives on the efficacy of COVID‐19 vaccines. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Diabetes is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Unravelling the molecular mechanisms that account for functional pleiotropy is a major challenge for researchers in cytokine biology. Cytokine–receptor cross-reactivity and shared signalling pathways are considered primary drivers of cytokine pleiotropy. However, reports epitomized by studies of Jak-STAT cytokine signalling identify interesting biochemical and epigenetic determinants of transcription factor regulation that affect the delivery of signaldependent cytokine responses. Here, a regulatory interplay between STAT transcription factors and their convergence to specific genomic enhancers support the fine-tuning of cytokine responses controlling host immunity, functional identity, and tissue homeostasis and repair. In this review, we provide an overview of the signalling networks that shape the way cells sense and interpret cytokine cues. With an emphasis on the biology of interleukin-6, we highlight the importance of these mechanisms to both physiological processes and pathophysiological outcomes. [ABSTRACT FROM AUTHOR]

A central question in immunology is what features allow the immune system to respond in a timely manner to a variety of pathogens encountered at unanticipated times and diverse body sites. Two decades of advanced and static dynamic imaging methods have now revealed several major principles facilitating host defense. Suborgan spatial prepositioning of distinct cells promotes time‐efficient interactions upon pathogen sensing. Such pre‐organization also provides an effective barrier to movement of pathogens from parenchymal tissues into the blood circulation. Various molecular mechanisms maintain effective intercellular communication among otherwise rapidly moving cells. These and related discoveries have benefited from recent increases in the number of parameters that can be measured simultaneously in a single tissue section and the extension of such multiplex analyses to 3D tissue volumes. The application of new computational methods to such imaging data has provided a quantitative, in vivo context for cell trafficking and signaling pathways traditionally explored in vitro or with dissociated cell preparations. Here, we summarize our efforts to devise and employ diverse imaging tools to probe immune system organization and function, concluding with a commentary on future developments, which we believe will reveal even more about how the immune system operates in health and disease. [ABSTRACT FROM AUTHOR]

To explore the potential involvement of the chemokine system in synoviocyte‐mediated tissue destruction in rheumatoid arthritis (RA), we studied the expression profile of chemokine receptors and their function in the migration, proliferation, and matrix metalloproteinase (MMP) production of cultured fibroblast‐like synoviocytes (FLS) from RA patients.The presence of CC and CXC chemokine receptors on cultured FLS was studied at the messenger RNA (mRNA) level by reverse transcriptase–polymerase chain reaction and at the cell surface expression level by flow cytometry. Variations in cytosolic calcium influx induced by chemokine stimulation were assessed by flow cytometry on Fura Red–preloaded FLS. Two‐compartment transwell chambers were used for FLS chemotaxis assays. Cell growth was measured by a fluorescence‐based proliferation assay. Gelatinase and collagenase activities were determined by a fibril degradation assay and zymography.FLS constitutively expressed the receptors CCR2, CCR5, CXCR3, and CXCR4, both at the cell surface and mRNA levels, but failed to express CCR3 and CCR6. Significant intracytosolic calcium influx was observed on FLS challenged with monocyte chemotactic protein 1 (MCP‐1), stromal cell–derived factor 1α (SDF‐1α), and interferon‐inducible protein 10 (IP‐10). Stimulation with MCP‐1, SDF‐1α, IP‐10, and monokine induced by interferon‐γ enhanced the migration and proliferation of FLS. These chemokines, in addition to RANTES, increased in a dose‐ and time‐dependent manner the gelatinase and collagenase activities in cell‐free supernatants of cultured FLS. Interestingly, the chemokine‐mediated up‐regulation of MMP activities was significantly abrogated by the presence of anti–interleukin‐1β, but not anti–tumor necrosis factor α, blocking antibodies.These data suggest that through modulation of the migration, proliferation, and MMP production by FLS, the chemokine system may play a more direct role in the destructive phase of RA than is currently suspected, and thus emphasize the relevance of chemokines and their receptors as potential therapeutic targets in this disease. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Rheumatoid synovium is characterized by hyperplasia of fibroblast-like (type B) synoviocytes (FLS), infiltration with mononuclear leukocytes, and tissue hypoxia. Although the latter is well documented, it has received little attention in dissection of the biochemical events that mediate the inflammatory lesion in rheumatoid arthritis (RA). Therefore, this study was designed to assess the effect of hypoxia on FLS responses to the monokine interleukin-1beta (IL-1beta) and to monocyte conditioned medium. METHODS: FLS obtained from serial cultures of synovial fluid aspirates were treated with IL-1beta or monocyte conditioned medium, under normoxia and hypoxia. RESULTS: In hypoxia, transcription of cyclooxygenase 2 (COX-2), expression of COX-2 protein, and production of COX-2-derived eicosanoids and matrix metalloproteinase (MMP) activity by FLS were all increased in response to IL-1beta. In contrast to our recent observations concerning monocytes, there was no change in COX-2 message stability and cytosolic phospholipase A2 activity in the FLS under hypoxia. Treatment of monocyte conditioned medium with an IL-1beta blocking antibody showed that most of the effect of the conditioned medium was attributable to IL-1beta. CONCLUSION: The findings suggest that hypoxia is an important factor in aggravating the inflammatory lesion in RA, through increased production of COX-2-derived nociceptive eicosanoids and increased release of tissue-damaging MMPs. [ABSTRACT FROM AUTHOR]

Rheumatoid synovium is characterized by hyperplasia of fibroblast‐like (type B) synoviocytes (FLS), infiltration with mononuclear leukocytes, and tissue hypoxia. Although the latter is well documented, it has received little attention in dissection of the biochemical events that mediate the inflammatory lesion in rheumatoid arthritis (RA). Therefore, this study was designed to assess the effect of hypoxia on FLS responses to the monokine interleukin‐1β (IL‐1β) and to monocyte conditioned medium. FLS obtained from serial cultures of synovial fluid aspirates were treated with IL‐1β or monocyte conditioned medium, under normoxia and hypoxia. In hypoxia, transcription of cyclooxygenase 2 (COX‐2), expression of COX‐2 protein, and production of COX‐2–derived eicosanoids and matrix metalloproteinase (MMP) activity by FLS were all increased in response to IL‐1β. In contrast to our recent observations concerning monocytes, there was no change in COX‐2 message stability and cytosolic phospholipase A2 activity in the FLS under hypoxia. Treatment of monocyte conditioned medium with an IL‐1β blocking antibody showed that most of the effect of the conditioned medium was attributable to IL‐1β. The findings suggest that hypoxia is an important factor in aggravating the inflammatory lesion in RA, through increased production of COX‐2–derived nociceptive eicosanoids and increased release of tissue‐damaging MMPs. [ABSTRACT FROM AUTHOR]

Monokine Induced by Interferon-γ (MIG), a CXC chemokine, is a potent inducer of T-cell chemotaxis and activation and has been implicated in the host response to viral infections and tumor immunity as well as in the pathogenesis of autoimmunity and transplant rejection. Although it is known that the Toll-Like Receptor-4 (TLR-4) ligand LPS synergizes with IFN-γ to induce MIG expression in macrophages, the molecular mechanisms responsible for the synergy have yet to be elucidated. We determined that the marked synergy between LPS and IFN-γ on MIG mRNA expression in mouse macrophages is a result of LPS-induced NF-κB and IFN-γ-induced STAT. The synergy was not dependent on new protein synthesis, was independent of TNF-α, and occurred at the level of gene transcription. We identified 2 NF-κB sites located at -154 and -129 of the MIG promoter proximal to the γ-responsive element that mediated this effect. Finally, we demonstrated that other TLR ligands (zymosan, double stranded RNA and CpG) synergized with IFN-γ to induce MIG in an NF-κB dependent fashion. These data emphasize the ability of bacterial and viral products to activate/modify immune responses and promote adaptive T cell immunity through the NF-κB pathway. [ABSTRACT FROM AUTHOR]

To extend the study of the chemokine receptor repertoire on human chondrocytes to receptors with reported housekeeping functions (CXCR3, CXCR4, CXCR5, and CCR6) and to evaluate whether ligands of these receptors play a role in chondrocyte phenotype modulation and proliferation. Chemokine receptor expression was determined by flow cytometry. Subcultures of chondrocytes were collected and fixed at confluence or during the exponential phase of growth and analyzed for chemokine receptor modulation. The effects of chemokines on isolated cells as well as chondrocytes cultured within an intact extracellular matrix were investigated. Isolated human chondrocytes were stimulated with 100 nM chemokines (monokine induced by interferon-γ, stromal cell–derived factor 1α [SDF-1α], B cell–attracting chemokine 1 [BCA-1], or macrophage inflammatory protein 3α), and conditioned media were assessed for matrix-degrading enzyme contents (matrix metalloproteinases [MMPs] 1, 3, and 13, and N-acetyl-β-D-glucosaminidase [NAG]). Cell proliferation and phenotype modulation were evaluated by bromodeoxyuridine incorporation and cathepsin B production. Induction of cell proliferation was assessed in cartilage explants by immunodetection of the proliferation-associated antigen S100A4. CXCR3, CXCR4, CXCR5, and CCR6 were detected on human chondrocytes. CXCR3 and CXCR4 expression was increased in exponentially growing chondrocyte subcultures. Ligands of all receptors enhanced the release of MMPs 1, 3, and 13. Release of NAG and cathepsin B was significantly higher in chemokine-stimulated cultures than in unstimulated cultures. SDF-1α and BCA-1 also induced DNA synthesis and chondrocyte proliferation, as was shown by the up-regulation of S100A4 in cartilage explants as well. Our findings extend the repertoire of functional responses elicited by the activity of chemokines on chondrocytes and open new avenues in our understanding of the control of chondrocyte differentiation status by chemokines and their receptors. [ABSTRACT FROM AUTHOR]

CXCR3, predominately expressed on memory/activated T cells, is a receptor for both interferon-γ inducible protein-10/CXC ligand 10 (CXCL10) and monokine induced by interferon-γ/CXCL9. We reported here that CXCR3 was highly up-regulated on infiltrating eosinophils in Schistosoma japonicum egg-induced granuloma in the mouse liver. It was also highly and functionally up-regulated on peritoneal exudate eosinophils in mice infected with S. japonicum. The phenomena were demonstrated at protein and mRNA levels using immunohisto- and immunocytochemistry evaluation of biopsy, flow cytometry and real-time quantitative reverse transcriptase–polymerase chain reaction technique, and verified by Northern blotting and chemotaxis assay in vitro. We also found that CCR3 expression on the infiltrating and peritoneal exudate cells was significantly decreased, CXCR4 expression was unchanged during the 42-day period of infection. We screened mRNA expression levels of the all known chemokine receptors in purified peritoneal exudate eosinophils and liver granuloma dominated by eosinophils. CXCR3 was highly and functionally up-regulated on peritoneal exudate eosinophils in mice infected with S. japonicum, meanwhile CCR3 was significantly and functionally down-regulated in these cells. The findings could lead to a better understanding of the chemokine receptor expression pattern of eosinophils at inflamed tissue sites caused by parasites. These could be also crucial for establishing a therapeutic strategy for eosinophilic inflammation via intervention in chemokine actions. [ABSTRACT FROM AUTHOR]

Classical Hodgkin lymphoma (HL) is characterized by the presence of Hodgkin and Reed-Sternberg cells (H&RS) and a prominent lymphocytic infiltration. We previously reported Hodgkin-like adult T-cell leukemia/lymphoma (HL-like ATLL) (new WHO classification). Various CXC and CC chemokines are expressed on H&RS cells and the relationships between chemokines and the chemokine receptor (R) are thought to be important for selectivity of local immunity of Th1 and Th2 T cells. To clarify the role of T-cell immunity in classical HL and Hodgkin-like ATLL, we performed gene expression profiling (chemokine, chemokine R and cytokine DNA chips) in 12 cases {classical HL, 8 cases [mixed cellularity (MC) type, 4; nodular sclerosis (NS) type, 4]; Hodgkin-like ATLL, 4 cases} and immunohistochemical staining in 29 cases (MC, 10; NS, 10; Hodgkin-like ATLL, 9). EBV-infected H&RS cells were detected in 9 of 10 cases of HL MC, 5 of 9 of HL-like ATLL and 2 of 10 HL NS. T-cell-directed chemokine thymus- and activation-regulated chemokine (TARC)- and/or macrophage-derived chemokine (MDC)-positive H&RS cells were detected in all 20 cases of HL MC and HL NS but only in 5 of 9 cases of HL-like ATLL. Interferon-γ-inducible protein-10 (IP10)- and monokine induced by interferon-γ (MIG)-positive H&RS cells were detected in all 10 HL MC but only in 5 of 10 cases of HL NS and 2 of 9 cases of HL-like ATLL. However, 2 of 5 cases of HL-like ATLL with EBV infection and 2 of 2 HL NS with EBV had IP10/MIG-positive H&RS cells. The chemokine expressions in H&RS cells seemed to be associated with EBV infection rather than histologic subtypes. In the DNA chip expression analysis, classical HL and HL-like ATLL had a mixed Th1/Th2-type profile, and HL MC (EBV-positive) and HL NS (EBV-negative) were differentially clustered. However, 2 cases of HL-like ATLL clustered with HL MS and the other 2 cases of HL-like ATLL clustered with HL NS. The former HL-like ATLL had EBV infection in H&RS cells, whereas the latter did not have EBV infection. This finding also suggests that EBV might influence local expression of chemokines rather than HL subtypes. Our results indicate that local immunologic disorder or imbalance appears to influence the formation of H&RS cells and that in HL-like ATLL, HTLV-1 infection might not be necessary for H&RS cell formation. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Neutrophils are known to play an important role in inflammatory responses by virtue of their ability to perform a series of effector functions that collectively represent a major mechanism of innate immunity against injury infection. In recent years, however, it has become obvious that the contribution of neutrophils to host defence and natural immunity extends well beyond their traditional role as professional phagocytes. Indeed, neutrophils can be induced to express a number of genes whose products lie at the core of inflammatory and immune response. These include not only Fc receptors, complement components, cationic antimicrobial and NADPH oxidase proteins, but also a variety of cytokines (including tumour necrosis factors-α, interleukin (IL)-1Β, IL-1Rα, IL-12 and vascular endothelial growth factor), and chemokines such as IL-8, growth-related gene product, macrophage inflammatory protein (MIP)-1α, MIP-1Β interferon-γ-inducible protein of 10 kDa and monokine induced by interferon-γ. Because these chemokines are primarily chemotactic for neutrophils, monocytes, immature dendritic cells and T-lymphocyte subsets, a potential role for neutrophils in orchestrating the sequential recruitment of distinct leukocyte types to the inflamed tissue is likely to occur. The purpose of this review is to summarize the essential features of the production of chemokines by polymorphonuclear neutrophil leukocytes and the contribution that we have made to characterize some aspects of this newly discovered crucial function of neutrophils. [ABSTRACT FROM AUTHOR]

Background: Cerebral Aβ is the hallmark of the AD in the early therapeutic intervention as well as diagnosis of the disease. Detecting in‐vivo Aβ deposition, however, still have limited accessibility. In this respect, the current study aims to identify plasma markers related to cerebral Aβ status via simple machine learning approach. Methods: Predictability of the candidate plasma markers for cerebral Aβ burden was examined by analyzing 303 non‐demented participants those who had rules based medicine (RMB) and amyloid PET data from the ADNI cohort at baseline visit (83 control and 220 with MCI). Demographic variables (age, gender, education, and APOE status), and 146 of 190 plasma analytes passed quality check were selected as input in learning vector quantization (LVQ) model. The cerebral Aβ burden was measured using PiB PET images. Predictability and importance of variable were calculated using LVQ model. Results: LVQ model with 10‐cross validation predicted cerebral Aβ status with the 90.67% accuracy (balanced accuracy: 93.14%) in non‐demented people. Based on variable importance analysis, Top‐10 variables above importance ratio above 60 after rescaling were selected: APOE carrier status (100.00), Angiotensin‐Converting Enzyme (ACE, 92.77), Eotaxin‐3 (89.74), Chromogranin A (CgA, 83.61), Brain Natriuretic Peptide (BNP, 79.61), Creatine Kinase‐MB (CK‐MB, 69.61), Monokine Induced by Gamma Interferon (68.26), T Lymphocyte‐Secreted Protein I‐309 (I‐309, 66.89), Matrix Metalloproteinase‐9 (MMP‐9, 64.52), Matrix Metalloproteinase‐9 total (MMP‐9 total, 60.90). Conclusions: Our findings demonstrated that plasma based analytes can predict the cerebral Aβ positivity in non‐demented people. More specifically, ACE is can be a candidate marker for early detection of Aβ deposition in the asymptomatic stage of dementia. Plus, Eoxatain, and CgA can also play a role in AD pathology. To this end, this research was supported by the MSIT (Ministry of Science and ICT), Korea, under the ITRC (Information Technology Research Center) support program(IITP‐2021‐2017‐0‐01630) supervised by the IITP (Institute for Information & communications Technology Promotion). [ABSTRACT FROM AUTHOR]

Background: Monocyte chemoattractant protein‐1 (MCP‐1) is highly expressed by lymphocytes at skin sites affected by alopecia areata (AA). Variations in MCP‐1 as well as in methylene‐tetrahydrofolate reductase (MTHFR), a key enzyme related to many inflammatory pathologies, have been associated with several autoimmune disorders. This study was designed to test a possible association between MCP‐1 and MTHFR variations and altered expression of their genes and the risk of AA. Methods: Blood samples of patients (60) suffering from AA as well as healthy subjects (60) were collected. Gene expression levels of MCP‐1 and MTHFR were evaluated by real‐time reverse‐transcription polymerase chain reaction analysis. Moreover, MCP‐1 rs1024611 (A‐2518G) and MTHFR rs1801133 (C677T) polymorphisms were genotyped by using polymerase chain reaction‐restriction fragment length polymorphism assays. Results: In contrast to MCP‐1, the MTHFR gene expression was found to be significantly higher in patients than in controls. Further stratification of the patients revealed that polymorphic genotypes in MCP‐1 (AG + GG) and MTHFR (CT + TT) could significantly alter gene expression levels. Elevation of MCP‐1 expression was significantly associated with the total number of variant MCP‐1 and MTHFR alleles. However, no statistically significant difference was noticed in the genotypic distribution of MCP‐1 and MTHFR variations between patients and controls. Conclusion: In summary, despite MCP‐1 rs1024611 and MTHFR rs1801133 variations are not associated with AA risk, they may implicate the disease pathogenesis by influencing MCP‐1 activity. [ABSTRACT FROM AUTHOR]

In chronic hepatitis B (CHB) and C (CHC) infections, the composition of the immune cell microenvironment at the site of infection is poorly understood. Thus, our aim was to characterize and compare liver infiltrates to identify shared and exclusive hepatic immune components. Immunohistochemistry was performed on 26 CHB and 42 CHC liver biopsies to determine Th (CD4+), Th1 (T‐bet+), Th17 (IL‐17A+), Treg (Foxp3+) and CTL (CD8+) cells frequency in portal/periportal and intralobular areas and relate them to liver damage. CHB and CHC cases shared a portal/periportal CD4+ lymphocyte predominance and a lobular CD8+ lymphocyte majority. However, CHC exhibited a concomitant lobular T‐bet+ cell dominance while in CHB FoxP3+ cells prevail. CHC disclosed higher frequencies of P/P FoxP3+, IL‐17A+ and T‐bet+ cells and intralobular CD4+, IL‐17A+ and T‐bet+ lymphocytes. HBeAg+ chronic hepatitis and CHC cell frequencies were similar except for lobular T‐bet+ that remained higher among CHC cases. Comparison among cases with less severe liver disease revealed lower lymphocyte frequencies in CHB samples, while no differences were observed between patients with more severe stages. Interestingly, in CHB portal/periportal CD4+ and lobular CD4+, CD8+ and IL‐17A+ cells were associated with severe hepatitis. Even when all studied populations were identified in both infections preferential lymphocyte frequencies and prevalence at different areas along with their association with liver damage highlighted that CHB and CHC immune responses are not the same. [ABSTRACT FROM AUTHOR]

Infection and malignant tumors are the most common diseases in people's daily life, which seriously threaten human health. Because of the frequent and extensive administration of antibiotics and chemodrugs, the prevalence of multidrug‐resistant bacteria and tumor cells makes the conventional therapies less effective and even invalid. To overcome the repugnant dilemma, herein the authors devise and develop a hollow Cu2−XS nano‐homojunction (nano‐HJ) platform for the effective eradication of both bacteria and tumors upon tissue‐penetrable near‐infrared (NIR) light irradiation. Hyaluronan (HA) is covalently decorated onto the nano‐homojunctions (nano‐HJs) surface to enhance their biocompatibility, tumor‐targeting ability, and cutaneous wound healing capability. The decorated nano‐HJs exert robust NIR‐activatable bactericidal modality and accelerate the cutaneous regeneration of bacteria‐invaded full‐thickness wounds through the synergy of photothermal/photodynamic effects, glutathione depletion, and HA assistance. After loading anticancer drug doxorubicin in the cavity of nano‐HJs, the antitumor therapy efficacy is greatly strengthened both in vitro and in vivo by the collaborative photo‐chemotherapy. Accordingly, this work not only highlights the great promise of the Cu2−XS nano‐HJs in the treatment of bacteria‐induced contagious diseases and malignant tumors but also opens up a new research direction for the biomedical application of homojunction nanoplatforms in the future. [ABSTRACT FROM AUTHOR]

Macrophages are leukocytes that play a strategic role in immune response and can be associated with various diseases due to their effects on the inflammation process and oxidative events. The current study was evaluated the anti‐inflammatory and antioxidant properties of cinnamaldehyde and eugenol, which are phyto‐compounds with numerous bioactive properties, on lipopolysaccharide (LPS)‐induced macrophage cells. For this purpose, Raw 264.7 cells were incubated with cinnamaldehyde or eugenol (15, 25, and 50 μM) then stimulated with LPS. After 24 hr, tumor necrosis factor‐alpha (TNF‐α), interleukin‐1β (IL‐1β), and IL‐6 levels (as inflammatory mediators), and malondialdehyde (MDA) and nitric oxide (NOx) levels as well as superoxide dismutase (SOD) and catalase (CAT) activities (as oxidative status markers) were determined in cell cultures. Cinnamaldehyde and eugenol pre‐treatments decreased TNF‐α, IL‐1β, and IL‐6 levels as compared to LPS group at all concentrations. Furthermore, these pre‐treatments increased SOD activity while decreased MDA and NOx levels as well as CAT activity at different concentrations. Our results demonstrated that these phyto‐compounds have potential for the treatment of various diseases as protective agents against chronic inflammation and oxidative stress. Practical applications: Chronic inflammation and oxidative stress are complications that play a detrimental role in the pathophysiology of many diseases. Alternative treatment methods have been investigated to prevent them. Cinnamaldehyde and eugenol are phyto‐compounds with high bioactivity that can be obtained from foods and spices. In this study, the protective effects of cinnamaldehyde and eugenol on lipopolysaccharide‐induced oxidative stress and inflammation in macrophage cells were investigated. According to the obtained results, cinnamaldehyde and eugenol pre‐treatments decreased inflammation and also reduced oxidative stress. Cinnamaldehyde and eugenol may be a better natural alternative protective agent for the chronic inflammation‐ and oxidative stress‐related diseases. [ABSTRACT FROM AUTHOR]

Hip implants are a successful solution for osteoarthritis; however, some individuals with metal‐on‐metal (MoM) and metal‐on‐polyethylene (MoP) prosthetics develop adverse local tissue reactions (ALTRs). While MoM and MoP ALTRs are presumed to be delayed hypersensitivity reactions to corrosion products, MoM‐ and MoP‐associated ALTRs present with different histological characteristics. We compared MoM‐ and MoP‐associated ALTRs histopathology with cobalt and chromium levels in serum and synovial fluid. We analyzed the gene expression levels of leukocyte aggregates and synovial fluid chemokines/cytokines to resolve potential pathophysiologic differences. In addition, we classified ALTRs from 79 patients according to their leukocyte infiltrates as macrophage‐dominant, mixed, and lymphocyte‐dominant. Immune‐related transcript profiles from lymphocyte‐dominant MoM‐ and MoP‐associated ALTR patients with perivascular lymphocytic aggregates were similar. Cell signatures indicated predominantly macrophage, Th1 and Th2 lymphocytic infiltrate, with strong exhausted CD8+ signature, and low Th17 and B cell, relative to healthy lymph nodes. Lymphocyte‐dominant ALTR‐associated synovial fluid contained higher levels of induced protein 10 (IP‐10), interleukin‐1 receptor antagonist (IL‐1RN), IL‐8, IL‐6, IL‐16, macrophage inflammatory protein 1 (MIP‐1α), IL‐18, MCP‐2, and lower cell‐attracting chemokine levels, when compared with prosthetic revisions lacking ALTRs. In addition, the higher levels of IP‐10, IL‐8, IL‐6, MIP‐1α, and MCP‐2 were observed within the synovial fluid of the lymphocyte‐dominant ALTRs relative to the macrophage‐dominant ALTRs. Not all cytokines/chemokines were detected in the perivascular aggregate transcripts, suggesting the existence of other sources in the affected synovia. Our results support the hypothesis of common hypersensitivity pathogenesis in lymphocyte‐dominant MoM and MoP ALTRs. The exhausted lymphocyte signature indicates chronic processes and an impaired immune response, although the cause of the persistent T‐cell activation remains unclear. The cytokine/chemokine signature of lymphocyte‐dominant‐associated ATLRs may be of utility for diagnosing this more aggressive pathogenesis. [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of PF‐06650833, a highly potent and selective small‐molecule inhibitor of interleukin‐1–associated kinase 4 (IRAK4), in autoimmune pathophysiology in vitro, in vivo, and in the clinical setting. Methods: Rheumatoid arthritis (RA) inflammatory pathophysiology was modeled in vitro through 1) stimulation of primary human macrophages with anti–citrullinated protein antibody immune complexes (ICs), 2) RA fibroblast‐like synoviocyte (FLS) cultures stimulated with Toll‐like receptor (TLR) ligands, as well as 3) additional human primary cell cocultures exposed to inflammatory stimuli. Systemic lupus erythematosus (SLE) pathophysiology was simulated in human neutrophils, dendritic cells, B cells, and peripheral blood mononuclear cells stimulated with TLR ligands and SLE patient ICs. PF‐06650833 was evaluated in vivo in the rat collagen‐induced arthritis (CIA) model and the mouse pristane‐induced and MRL/lpr models of lupus. Finally, RNA sequencing data generated with whole blood samples from a phase I multiple‐ascending‐dose clinical trial of PF‐06650833 were used to test in vivo human pharmacology. Results: In vitro, PF‐06650833 inhibited human primary cell inflammatory responses to physiologically relevant stimuli generated with RA and SLE patient plasma. In vivo, PF‐06650833 reduced circulating autoantibody levels in the pristane‐induced and MRL/lpr murine models of lupus and protected against CIA in rats. In a phase I clinical trial (NCT02485769), PF‐06650833 demonstrated in vivo pharmacologic action pertinent to SLE by reducing whole blood interferon gene signature expression in healthy volunteers. Conclusion: These data demonstrate that inhibition of IRAK4 kinase activity can reduce levels of inflammation markers in humans and provide confidence in the rationale for clinical development of IRAK4 inhibitors for rheumatologic indications. [ABSTRACT FROM AUTHOR]

Background: Chemokines are important mediators in immune cell recruitment, contributing to allergy development. However, extensive studies of chemokines in the circulation in relation to the presence and development of allergic diseases remain scarce. Our aim was to investigate associations of circulating allergy‐related chemokines with the development of asthma and sensitization cross‐sectionally and longitudinally in a population‐based cohort. Methods: The chemokines CCL17, CCL22, CXCL10, CXCL11 and CCL18 were measured in plasma samples from children in the Manchester Asthma and Allergy Study. Samples were available from cord blood at birth (n = 376), age 1 (n = 195) and age 8 (n = 334). Cross‐sectional and longitudinal association analyses were performed in relation to asthma and allergic sensitization, as well as allergic phenotype clusters previously derived using machine learning in the same study population. Results: In children with asthma and/or allergic sensitization, CCL18 levels were consistently elevated at 1 and/or 8 years of ages. In a longitudinal model including information on asthma from 4 time points (5, 8, 11 and 16 years of ages), we observed a significant association between increasing CCL18 levels at age 1 and a higher risk of asthma from early school age to adolescence (OR = 2.9, 95% CI 1.1–7.6, p =.028). We observed similar associations in longitudinal models for allergic sensitization. Asthma later in life was preceded by increased CXCL10 levels after birth and decreased CXCL11 levels at birth. Conclusion: Elevated CCL18 levels throughout childhood precede the development of asthma and allergic sensitization. The Th1‐associated chemokines CXCL10 and CXCL11 also associated with the development of both outcomes, with differential temporal effects. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) accounts for about 2% to 3% of adult malignancies, and clear cell renal cell carcinoma (ccRCC) is the most common and aggressive type of kidney cancer. It accounts for 75% of all kidney tumors. Although new targeted drugs continue to appear, they are still not suitable for all patients. Therefore, an in-depth study of the molecular mechanism of the development of ccRCC and exploration of new targets for the treatment of ccRCC will help to achieve precise treatment for ccRCC. With the development of molecular research, the study of long noncoding RNA (LncRNA) has given us a new understanding of tumors. Although LncRNA does not encode proteins, it directly interacts with proteins in various signaling pathways and affects cell functions. Therefore, it is of great significance to study the mechanism of LncRNA in ccRCC. The expression level of Linc00472 in ccRCC tissues is significantly lower than adjacent normal tissues, and its low expression is closely related to Furman's high grade. The low expression of Linc00472 is associated with poor prognosis in patients with ccRCC. The results of protein interaction and functional enrichment analysis indicate that genes upregulated in renal clear cell carcinoma may play a major role. Analysis of target gene prediction results showed that Linc00472 may be used as ceRNA in the miR-24-3p-HLA-DPB1 pathway, miR-24-3p-CXCL9 pathway, miR-221-3p-C3aR1-VEGFR2 pathway, miR-17-5p-HLA-DQA1/HLA-DQB1 pathway, and miR-17-5p-C3aR1/C5aR1-VEGFR2 pathway which play important functions. In addition, the regulatory relationship between miR-24-3p and TNFR2 (TNFRSF1B), CD36, and COL4A1 should also be noted. The value of Linc00472 in the diagnosis and treatment of ccRCC is worthy of further study. [ABSTRACT FROM AUTHOR]

Background: Nicotinamide (vitamin B3) is a metabolite of tryptophan and dietary precursor of enzymes involved in many regulatory processes, which may influence fetal immune development. Objective: We examined whether maternal plasma concentrations of nicotinamide, tryptophan or nine related tryptophan metabolites during pregnancy were associated with the risk of development of infant eczema, wheeze, rhinitis or allergic sensitization. Methods: In the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) study, we analysed the associations between maternal plasma levels of nicotinamide, tryptophan and tryptophan metabolites at 26–28 weeks of gestation and allergic outcomes collected through interviewer‐administered questionnaires at multiple time‐points and skin prick testing to egg, milk, peanut and mites at age 18 months. Multivariate analysis was undertaken adjusting for all metabolites measured and separately adjusting for relevant demographic and environmental exposures. Analyses were also adjusted for multiple comparisons using the false discovery method. Results: Tryptophan metabolites were evaluated in 976/1247 (78%) women enrolled in GUSTO. In multivariate analysis including all metabolites, maternal plasma 3‐hydrokynurenine was associated with increased allergic sensitization at 18 months (AdjRR 2.6, 95% CI 1.3–5.2 for highest quartile) but the association with nicotinamide was not significant (AdjRR 1.8, 95% CI 0.9–3.6). In analysis adjusting for other exposures, both 3‐hydrokynurenine and nicotinamide were associated with increased allergic sensitization (AdjRR 2.0, 95% CI 1.1–3.6 for both metabolites). High maternal plasma nicotinamide was associated with increased infant eczema diagnosis by 6 and 12 months, which was not significant when adjusting for all metabolites measured, but was significant when adjusting for relevant environmental and demographic exposures. Other metabolites measured were not associated with allergic sensitization or eczema, and maternal tryptophan metabolites were not associated with offspring rhinitis and wheeze. Conclusions and Clinical Relevance: Maternal tryptophan metabolism during pregnancy may influence the development of allergic sensitization and eczema in infants. [ABSTRACT FROM AUTHOR]

Variants of UNC13D were most frequently detected (in 5 patients (10% of total)), followed by NOD2 (4 patients (8%)), LRBA (4 variants in 3 patients), and RNASEH2A in 3 patients (6%). B Methods: b A survey was conducted with patients with NPC and caregivers of patients with NPC (n=49; patient age: 13 months to 65 years) to assess patients' disease severity, the importance of NPC-related symptoms, and how symptoms affect patients' and caregivers' activities of daily living (ADLs) and health-related QoL (HRQoL). OA was the only treatment administered for 22 patients (31.9%); 28 patients (40.6%) received prior nusinersen treatment with no recorded doses after OA infusion; 15 patients (21.7%) received at least one nusinersen dose before, and at least one nusinersen or risdiplam dose after, OA infusion; 4 patients (5.8%) received nusinersen or risdiplam after OA. B Keywords: b Epilepsy 1 TABLEDemographics characteristics Abstract 232 HT

In humans, IL‐8 (CXCL8) is a key chemokine for chemotaxis of polymorphonuclear leukocytes and monocytes/macrophages when acting on CXCR1 and CXCR2. CXCL8 activity on neutrophils includes chemotaxis and eliciting the extrusion of neutrophil extracellular traps (NETs). In this study, we show that concentrations of IL‐8 that induce NETosis surpass in at least one order of magnitude those required to elicit chemoattraction in human neutrophils. IL‐8‐induced NETosis was less dependent on G‐proteins than migration, while extracellular Ca+2 chelation similarly inhibited both processes. Reactive oxygen species (ROS) were more important for NETosis than for chemotaxis as evidenced by neutralization with N‐acetyl ‐cysteine. Interestingly, selective blockade with anti‐CXCR1 mAb inhibited NETosis much more readily than chemotaxis, while pharmacological inhibition of both CXCR1 and CXCR2, or selective inhibition for CXCR2 alone, similarly inhibited both functions. Together, these results propose a model according to which low concentrations of IL‐8 in a gradient attract neutrophils to the inflammatory foci, while high receptor‐saturating concentrations of IL‐8 give rise to NETosis once leukocytes reach the core of the inflammatory insult. [ABSTRACT FROM AUTHOR]

Background: Access to safe, effective, and affordable contraception is important for women's health and essential to mitigate maternal and fetal mortality rates. The progestin‐based contraceptive depot medroxyprogesterone acetate (DMPA) is a popular contraceptive choice with a low failure rate and convenient administration schedule. Aim: In this review, we compiled observational data from human cohorts that examine how DMPA influences the mucosal biology of the female genital tract (FGT) that are essential in maintaining vaginal health, including resident immune cells, pro‐inflammatory cytokines, epithelial barrier function, and the vaginal microbiome Materials and Methods: This review focused on the recent published literature published in 2019 and 2020. Results: Recent longitudinal studies show that DMPA use associates with an immunosuppressive phenotype, increase in CD4+CCR5+ T cells, and alterations to growth factors. In agreement with previous meta‐analyses, DMPA use is associated with minimal effects of the composition of the vaginal microbiome. Cross‐sectional studies associate a more pro‐inflammatory relationship with DMPA, but these studies are confounded by inherent weaknesses of cross‐sectional studies, including differences in study group sizes, behaviors, and other variables that may affect genital inflammation. Discussion & Conclusion: These recent results indicate that the interactions between DMPA and the vaginal mucosa are complex emphasizing the need for comprehensive longitudinal studies that take into consideration the measurement of multiple biological parameters. [ABSTRACT FROM AUTHOR]

A 41-kDa protein, which was specifically phosphorylated upon incubation with natural purified murine interleukin 1, was recently identified by us [Martin, M., Lovett, D. H. and Resch, K. (1986) Immunobiology 171, 165-169] in highly purified plasma membranes from the human tumor cell line K 562. An in vitro assay was used to investigate and characterize the phosphorylation induced by interleukin 1, possibly involved in signal transduction and generation. Plasma membranes were incubated with radiolabeled ATP in the presence of purified natural murine interleukin 1, or recombinant human interleukin 1α and the pattern of phosphoproteins was studied after separation by SDS/PAGE and subsequent autoradiography. A 41-kDa protein (pp41) was specifically phosphorylated on a tyrosine residue in the presence of interleukin 1 in a dose- and time-dependent manner. The protein showed a weak background phosphorylation in the absence of monokine. Phosphorylation took place very efficiently at 0°C, whereas phosphatases were not active at that temperature. At 37 °C, a rapid dephosphorylation was observed which was inhibited specifically by Zn2+ and vanadate. The interleukin-1-specific induction of the phosphorylation could also be observed after detergent solubilization of the plasma membranes. Affinity labeling with an ATP analogue revealed an ATP-binding and cleaving site at 41 kDa. Interleukin 1 did not induce the phosphorylation of p41 in plasma membranes obtained from a subclone of K 562, which did not respond to interleukin 1 with growth inhibition, as was reported recently for the K 562 mother line [Lovett, D. H., Kozan, B., Hadam, M., Resch, K. and Gemsa, D. (1986) J. Immunol. 136, 340-347]. These data suggest that the interleukin-1 receptor is functionally linked to a protein-tyrosine kinase, which is implicated in its biological function. [ABSTRACT FROM AUTHOR]

Leucocytes and vascular cells interact closely in inflammation and immunity and cytokines are important mediators of this interaction. The present study was designed to define the capacity of human endothelial cells (HEC) to produce a monocyte-derived neutrophil chemotactic factor (provisionally termed IL-8). IL-8 is a polypeptide chemotactic for neutrophils originally identified in the culture supernatant of lipopolysaccharide (LPS)-stimulated monocytes. IL-1 induced high levels of production of neutrophil chemotactic activity in culture supernatants of HEC. Optimal stimulation of activity was observed when HEC were cultured with 10–100 ng/ml IL-1β for 16 hr. Anti-IL-8 antibody blocked the chemotactic activity for neutrophils of IL-1-activated HEC supernatants. IL-1-treated HEC expressed high levels of IL-8 mRNA transcripts, as assessed by Northern blot analysis. Tumour necrosis factor (TNF) and LPS, unlike the inflammatory monokine IL-6, also induced IL-8 expression. Nuclear run-off experiments revealed that IL-1 activated transcription of the IL-8 gene. The production of IL-8 may represent a mechanism whereby endothelial cells, exposed to inflammatory signals, participate in the regulation of neutrophil extravasation. [ABSTRACT FROM AUTHOR]

Human synovial fibroblast cell lines (HSN), established from tissues obtained from the knee joints of arthritis patients undergoing arthoplasty, were used to investigate the effects of human interleukin-1 (IL-1) β and turnout necrosis factor (TNF)α on proliferation and prostaglandin E2 (PGE2) secretion. IL-1β aad TNFα were equipotent stimulators of HSN proliferation. Classical non-steroidal anti-inflammatory drugs and glucocorticoids significantly augmented this effect. In addition, IL-1β and TNFα were potent inducers of PGE2 production while exogenous PGE2 was growth inhibiting. These data suggest that the secretion of PGE2 by monokine-stimulated HSN exerts a negative feedback signal. Further examination of IL-1β- and TNFα-induced PGE2 secretion revealed IL-1β to be a more potent stimulator; however, this observation may be due, in part, to differences in the kinetics of induction. Rabbit anti-IL-1β and anti-TNFα specifically neutralized both proliferation and PGE: production induced by these monokines, but anti-IL-1β (or anti-IL-1α) did not block TNFα activity. It is unclear whether TNFα stimulates HSN to produce IL-1, but the antibody data suggest that extracellular IL-1 is not responsible for TNFα in vitro activity. [ABSTRACT FROM AUTHOR]

The injection of BCG vaccine in C57BL/6J mice results in the suppression of the generation of cytotoxic T lymphocytes (CTL) in mixed lymphocyte cultures (MLC) and of mitogenic rections to concanavalin A (Con A). Suppression is mediated by macrophage-like suppressor cells. Since previous work had indicated that suppression involved the inhibition of the production of interlcukin-2 (IL-2), the effects of BCO on interleukin-l (IL-1), a monokine required for IL-2 production, were investigated. It was found that the release of IL-l-like activity in spleen cell cultures stimulated with LPS or Con A was increased by previous BCG treatment of the cell donors. In MLC, the release of IL-l-like activity was also increased by BCG. However, the detection of IL- l -like activity in MLC supernatants was prevented by the presence of a suppressor factor. In this case, the IL-l- like activity could be separated with gel filtration from the suppressor factor which had higher molecular weight. The production of IL-I-like activity by CBA/J spleen cells, which are not suppressed by 8CC, was not significantly different from that of C57BL/63 cells, which are markedly suppressed. Moreover, the addition of IL-I to the BCG-suppressed cultures not only did not restore normal reactivity, but actually further suppressed CTL formation. It was concluded that BCG- induced suppression cannot be attributed to decreased IL-i activity. The suppressor factor discovered during these investigations may have a role in this type of suppression. [ABSTRACT FROM AUTHOR]

The effect of African swine fever virus replication on T and B lymphocytes was studied by mitogen-driven assays. Live attenuated isolates caused a marked suppressive effect which was dose- and time-dependent. This effect appeared to be mediated through a monokine. Live virulent isolates enhanced lymphocyte mitogenesis in most cases, with increased [³H]-thymidine uptake by T cells and increased Ig secretion by B cells. Killed preparation had no effect. These results are discussed in the light of the allergic response and immunopathological lesions produced by African swine fever virus infections. [ABSTRACT FROM AUTHOR]