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Background Atopic dermatitis (AD) is a heterogeneous, chronic inflammatory skin disease linked to skin microbiome dysbiosis with reduced bacterial diversity and elevated relative abundance of Staphylococcus aureus (S. aureus). Objectives We aimed to characterize the yet incompletely understood association between the skin microbiome and patients' demographic and clinical cofactors in relation to AD severity. Methods The skin microbiome in 48 adult moderate-to-severe AD patients was investigated using next-generation deep sequencing (16S rRNA gene, V1–V3 region) followed by denoising (DADA2) to obtain amplicon sequence variant (ASV) composition. Results In lesional skin, AD severity was associated with S. aureus relative abundance (rS = 0.53, p

Contains fulltext : 237768.pdf (Publisher’s version ) (Open Access) The two most common chronic inflammatory skin diseases are atopic dermatitis (AD) and psoriasis. The underpinnings of the remarkable degree of clinical heterogeneity of AD and psoriasis are poorly understood and, as a consequence, disease onset and progression are unpredictable and the optimal type and time point for intervention are as yet unknown. The BIOMAP project is the first IMI (Innovative Medicines Initiative) project dedicated to investigating the causes and mechanisms of AD and psoriasis and to identify potential biomarkers responsible for the variation in disease outcome. The consortium includes 7 large pharmaceutical companies and 25 non-industry partners including academia. Since there is mounting evidence supporting an important role for microbial exposures and our microbiota as factors mediating immune polarization and AD and psoriasis pathogenesis, an entire work package is dedicated to the investigation of skin and gut microbiome linked to AD or psoriasis. The large collaborative BIOMAP project will enable the integration of patient cohorts, data and knowledge in unprecedented proportions. The project has a unique opportunity with a potential to bridge and fill the gaps between current problems and solutions. This review highlights the power and potential of the BIOMAP project in the investigation of microbe-host interplay in AD and psoriasis.

Background: Morbidity and mortality from COVID-19 caused by novel coronavirus SARS-CoV-2 is accelerating worldwide, and novel clinical presentations of COVID-19 are often reported. The range of human cells and tissues targeted by SARS-CoV-2, its potential receptors and associated regulating factors are still largely unknown. The aim of our study was to analyze the expression of known and potential SARS-CoV-2 receptors and related molecules in the extensive collection of primary human cells and tissues from healthy subjects of different age and from patients with risk factors and known comorbidities of COVID-19. Methods: We performed RNA sequencing and explored available RNA-Seq databases to study gene expression and co-expression of ACE2, CD147 (BSG), and CD26 (DPP4) and their direct and indirect molecular partners in primary human bronchial epithelial cells, bronchial and skin biopsies, bronchoalveolar lavage fluid, whole blood, peripheral blood mononuclear cells (PBMCs), monocytes, neutrophils, DCs, NK cells, ILC1, ILC2, ILC3, CD4+ and CD8+ T cells, B cells, and plasmablasts. We analyzed the material from healthy children and adults, and from adults in relation to their disease or COVID-19 risk factor status. Results: ACE2 and TMPRSS2 were coexpressed at the epithelial sites of the lung and skin, whereas CD147 (BSG), cyclophilins (PPIA andPPIB), CD26 (DPP4), and related molecules were expressed in both epithelium and in immune cells. We also observed a distinct age-related expression profile of these genes in the PBMCs and T cells from healthy children and adults. Asthma, COPD, hypertension, smoking, obesity, and male gender status generally led to the higher expression of ACE2- and CD147-related genes in the bronchial biopsy, BAL, or blood. Additionally, CD147-related genes correlated positively with age and BMI. Interestingly, we also observed higher expression of CD147-related genes in the lesional skin of patients with atopic dermatitis. Conclusions: Our data suggest different receptor repertoire potentially involved in the SARS-CoV-2 infection at the epithelial barriers and in the immune cells. Altered expression of these receptors related to age, gender, obesity and smoking, as well as with the disease status, might contribute to COVID-19 morbidity and severity patterns. Keywords: COPD; COVID-19; COVID-19 children; SARS receptor; asthma; hypertension; obesity.

International audience; No abstract available

Background Markedly elevated levels of pro-inflammatory cytokines and defective type-I interferon responses were reported in COVID-19 patients. Objective This study aimed to determine whether particular cytokine profiles are associated with COVID-19 severity and mortality. Methods Cytokine concentrations and SARS-CoV-2 antigen were measured at hospital admission in serum of symptomatic COVID-19 patients (N=115), classified at hospitalization into three respiratory severity groups: no need for mechanical ventilatory support (No-MVS), intermediate severity requiring mechanical ventilatory support (MVS) and critical severity requiring extracorporeal membrane oxygenation (ECMO). Principal component analysis was used to characterize cytokine profiles associated with severity and mortality. The results were thereafter confirmed in an independent validation cohort (N=86). Results At time of hospitalization, ECMO patients presented a dominant pro-inflammatory response with elevated levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, IL-8 and IL-10. In contrast, an elevated type-I interferon response involving IFN-α and IFN-β was characteristic of No-MVS patients, whereas MVS patients exhibited both profiles. Mortality at one month was associated with higher levels of pro-inflammatory cytokines in ECMO patients, higher levels of type-I interferons in No-MVS patients and their combination in MVS patients, resulting in a combined mortality prediction accuracy of 88.5% (Risk Ratio 24.3, p, Graphical abstract, Capsule SummaryDistinct cytokine profiles are observed in association with COVID-19 severity and are differentially predictive of mortality in different oxygen support modalities. These results warrant personalized treatment of COVID-19 patients based on cytokine profiling.

International audience; Davoudi-Monfared et al. (1) report in this Journal the results from a clinical trial on COVID-19 patients showing that subcutaneous administration of interferon-β (IFN-β) was associated with a more rapid recovery from SARS-CoV-2 infection and decreased mortality.….

BackgroundMorbidity and mortality from COVID-19 caused by novel coronavirus SARS-CoV-2 is accelerating worldwide and novel clinical presentations of COVID-19 are often reported. The range of human cells and tissues targeted by SARS-CoV-2, its potential receptors and associated regulating factors are still largely unknown. The aim of our study was to analyze the expression of known and potential SARS-CoV-2 receptors and related molecules in the extensive collection of primary human cells and tissues from healthy subjects of different age and from patients with risk factors and known comorbidities of COVID-19.MethodsWe performed RNA sequencing and explored available RNA-Seq databases to study gene expression and co-expression of ACE2, CD147 (BSG), CD26 (DPP4) and their direct and indirect molecular partners in primary human bronchial epithelial cells, bronchial and skin biopsies, bronchoalveolar lavage fluid, whole blood, peripheral blood mononuclear cells (PBMCs), monocytes, neutrophils, DCs, NK cells, ILC1, ILC2, ILC3, CD4+and CD8+T cells, B cells and plasmablasts. We analyzed the material from healthy children and adults, and from adults in relation to their disease or COVID-19 risk factor status.ResultsACE2andTMPRSS2were coexpressed at the epithelial sites of the lung and skin, whereas CD147 (BSG), cyclophilins (PPIA and PPIB), CD26 (DPP4) and related molecules were expressed in both, epithelium and in immune cells. We also observed a distinct age-related expression profile of these genes in the PBMCs and T cells from healthy children and adults. Asthma, COPD, hypertension, smoking, obesity, and male gender status generally led to the higher expression of ACE2- and CD147-related genes in the bronchial biopsy, BAL or blood. Additionally, CD147-related genes correlated positively with age and BMI. Interestingly, we also observed higher expression of ACE2- and CD147-related genes in the lesional skin of patients with atopic dermatitis.ConclusionsOur data suggest different receptor repertoire potentially involved in the SARS-CoV-2 infection at the epithelial barriers and in the immune cells. Altered expression of these receptors related with age, gender, obesity and smoking, as well as with the disease status might contribute to COVID-19 morbidity and severity patterns.

The epithelial cell-derived cytokine milieu has been discussed as a “master switch” in the development of allergic disease.To understand the role of innate immune response in nasal epithelial cells during allergic inflammation, we created and established a fast and minimally invasive method to isolate and culture human nasal epithelial cells from clinically and immunologically well characterized patients. Human nasal epithelial cells from non-atopic volunteers and from allergic rhinitis patients were compared in respect to their growth, barrier integrity, pattern recognition, receptor expression, and immune responses to allergens and an array of pathogen-associated molecular patterns and inflammasome activators.Cells from nasal scrapings were clearly identified as nasal epithelial cells by staining of pan-Cytokeratin, Cytokeratin-14 and Tubulin. Additionally, Mucin 5AC staining revealed the presence of goblet cells, while staining of tight-junction protein Claudin-1, Occludin and ZO-1 showed the ability of the cells to form a tight barrier. Cells of atopic donors grew slower than cells of non-atopic donors. All nasal epithelial cells expressed TLR1-6 and 9, yet the expression of TLR-9 was lower in cells from allergic rhinitis (AR) donors. Additionally, epithelial cells from AR donors responded with a different TLR expression pattern to stimulation with TLR ligands. TLR-3 was the most potent modulator of cytokine and chemokine secretion in all human nasal epithelial cells (HNECs). The secretion of IL-1β, CCL-5, IL-8, IL-18 and IL-33 was elevated in HNECs of AR donors as compared to cells of non-atopic donors. This was observed in the steady-state (IL-18, IL-33) as well as under stimulation with TLR ligands (IL-18, IL-33, CCL-5, IL-8), aqueous pollen extracts (IL-18, IL-33), or the inflammasome activator Nigericin (IL-1β).In conclusion, nasal epithelial cells of AR donors show altered physical barrier responses in steady-state and in response to allergen stimulation. Cells of AR donors show increased expression of pro-inflammatory and IL-1 family cytokines at baseline and under stimulation, which could contribute to a micromilieu which is favorable for Th2. Keywords: Allergic rhinitis, Nasal epithelium, Pattern recognition receptor, Pollen, Inflammation

Background Pollen exposure induces local and systemic allergic immune responses in sensitized individuals, but nonsensitized individuals also are exposed to pollen. The kinetics of symptom expression under natural pollen exposure have never been systematically studied, especially in subjects without allergy. Objective We monitored the humoral immune response under natural pollen exposure to potentially uncover nasal biomarkers for in-season symptom severity and identify protective factors. Methods We compared humoral immune response kinetics in a panel study of subjects with seasonal allergic rhinitis (SAR) and subjects without allergy and tested for cross-sectional and interseasonal differences in levels of serum and nasal, total, and Betula verrucosa 1–specific immunoglobulin isotypes; immunoglobulin free light chains; cytokines; and chemokines. Nonsupervised principal component analysis was performed for all nasal immune variables, and single immune variables were correlated with in-season symptom severity by Spearman test. Results Symptoms followed airborne pollen concentrations in subjects with SAR, with a time lag between 0 and 13 days depending on the pollen type. Of the 7 subjects with nonallergy, 4 also exhibited in-season symptoms whereas 3 did not. Cumulative symptoms in those without allergy were lower than in those with SAR but followed the pollen exposure with similar kinetics. Nasal eotaxin-2, CCL22/MDC, and monocyte chemoattactant protein-1 (MCP-1) levels were higher in subjects with SAR, whereas IL-8 levels were higher in subjects without allergy. Principal component analysis and Spearman correlations identified nasal levels of IL-8, IL-33, and Betula verrucosa 1–specific IgG4 (sIgG4) and Betula verrucosa 1–specific IgE (sIgE) antibodies as predictive for seasonal symptom severity. Conclusions Nasal pollen–specific IgA and IgG isotypes are potentially protective within the humoral compartment. Nasal levels of IL-8, IL-33, sIgG4 and sIgE could be predictive biomarkers for pollen-specific symptom expression, irrespective of atopy.

Background Atopic eczema (atopic dermatitis, AD) is characterized by disrupted skin barrier associated with elevated skin pH and skin microbiome dysbiosis, due to high Staphylococcus aureus loads, especially during flares. Since S aureus shows optimal growth at neutral pH, we investigated the longitudinal interplay between these factors and AD severity in a pilot study. Method Emollient (with either basic pH 8.5 or pH 5.5) was applied double-blinded twice daily to 6 AD patients and 6 healthy (HE) controls for 8 weeks. Weekly, skin swabs for microbiome analysis (deep sequencing) were taken, AD severity was assessed, and skin physiology (pH, hydration, transepidermal water loss) was measured. Results Physiological, microbiome, and clinical results were not robustly related to the pH of applied emollient. In contrast to longitudinally stable microbiome in HE, S aureus frequency significantly increased in AD over 8 weeks. High S aureus abundance was associated with skin pH 5.7-6.2. High baseline S aureus frequency predicted both increase in S aureus and in AD severity (EASI and local SCORAD) after 8 weeks. Conclusion Skin pH is tightly regulated by intrinsic factors and limits the abundance of S aureus. High baseline S aureus abundance in turn predicts an increase in AD severity over the study period. This underlines the importance and potential of sustained intervention regarding the skin pH and urges for larger studies linking skin pH and skin S aureus abundance to understand driving factors of disease progression.

Background Group 2 innate lymphoid cells (ILC2s) play critical roles in induction and exacerbation of allergic airway inflammation. Thus clarification of the mechanisms that underlie regulation of ILC2 activation has received significant attention. Although innate lymphoid cells are divided into 3 major subsets that mirror helper effector T-cell subsets, counterpart subsets of regulatory T cells have not been well characterized. Objective We sought to determine the factors that induce regulatory innate lymphoid cells (ILCregs). Methods IL-10+ ILCregs induced from ILC2s by using retinoic acid (RA) were analyzed with RNA-sequencing and flow cytometry. ILCregs were evaluated in human nasal tissue from healthy subjects and patients with chronic rhinosinusitis with nasal polyps and lung tissue from house dust mite– or saline-treated mice. Results RA induced IL-10 secretion by human ILC2s but not type 2 cytokines. IL-10+ ILCregs, which were converted from ILC2s by means of RA stimulation, expressed a regulatory T cell–like signature with expression of IL-10, cytotoxic T lymphocyte–associated protein 4, and CD25, with downregulated effector type 2–related markers, such as chemoattractant receptor–homologous molecule on TH2 cells and ST2, and suppressed activation of CD4+ T cells and ILC2s. ILCregs were rarely detected in human nasal tissue from healthy subjects or lung tissue from saline-treated mice, but numbers were increased in nasal tissue from patients with chronic rhinosinusitis with nasal polyps and in lung tissue from house dust mite–treated mice. Enzymes for RA synthesis were upregulated in airway epithelial cells during type 2 inflammation in vivo and by IL-13 in vitro. Conclusion We have identified a unique immune regulatory and anti-inflammatory pathway by which RA converts ILC2s to ILCregs. Interactions between airway epithelial cells and ILC2s play an important roles in the generation of ILCregs.

Influenza vaccination is a common approach to prevent seasonal and pandemic influenza. Pre-existing antibodies against close viral strains might impair antibody formation against previously unseen strains–a process called original antigenic sin. The role of this pre-existing cellular immunity in this process is, despite some hints from animal models, not clear. Here, we analyzed cellular and humoral immunity in healthy individuals before and after vaccination with seasonal influenza vaccine. Based on influenza-specific hemagglutination inhibiting (HI) titers, vaccinees were grouped into HI-negative and -positive cohorts followed by in-depth cytometric and TCR repertoire analysis. Both serological groups revealed cross-reactive T-cell memory to the vaccine strains at baseline that gave rise to the majority of vaccine-specific T-cells post vaccination. On the contrary, very limited number of vaccine-specific T-cell clones was recruited from the naive pool. Furthermore, baseline quantity of vaccine-specific central memory helper T-cells and clonotype richness of this population directly correlated with the vaccination efficacy. Our findings suggest that the deliberate recruitment of pre-existing cross-reactive cellular memory might help to improve vaccination outcome.

Background IL-22 is potentially a pathogenic cytokine in patients with atopic dermatitis (AD), but the molecular effects of IL-22 antagonism have not been defined in human subjects. Objective We sought to evaluate the cellular and molecular effects of IL-22 blockade in tissues from patients with moderate-to-severe AD. Methods We assessed lesional and nonlesional skin from 59 patients with moderate-to-severe AD treated with anti–IL-22 (fezakinumab) versus placebo (2:1) using transcriptomic and immunohistochemistry analyses. Results Greater reversal of the AD genomic profile was seen with fezakinumab versus placebo, namely 25.3% versus 10.5% at 4 weeks (P = 1.7 × 10−5) and 65.5% versus 13.9% at 12 weeks (P = 9.5 × 10−19), respectively. Because IL-22 blockade showed clinical efficacy only in patients with severe AD, we used baseline median IL-22 mRNA expression to stratify for high (n = 30) and low (n = 29) IL-22 expression groups. Much stronger mean transcriptomic improvements were seen with fezakinumab in the IL-22–high drug-treated group (82.8% and 139.4% at 4 and 12 weeks, respectively) than in the respective IL-22–high placebo-treated group (39.6% and 56.3% at 4 and 12 weeks) or the IL-22–low groups. Significant downregulations of multiple immune pathways, including TH1/CXCL9, TH2/CCL18/CCL22, TH17/CCL20/DEFB4A, and TH22/IL22/S100A's, were restricted to the IL-22–high drug group (P Conclusions This is the first report showing a profound effect of IL-22 blockade on multiple inflammatory pathways in AD. These data, supported by robust effects in patients with high IL-22 baseline expression, suggest a central role for IL-22 in AD, indicating the need for a precision medicine approach for improving therapeutic outcomes in patients with AD.

Background Interleukin 22 promotes epidermal hyperplasia and inhibits skin barrier function. Objective Evaluate interleukin 22 blockade in adults with moderate-to-severe atopic dermatitis (AD). Methods We performed a randomized, double-blind, placebo-controlled trial with intravenous fezakinumab monotherapy every 2 weeks for 10 weeks, with follow-up assessments until 20 weeks. The change in SCOring AD (SCORAD) score from baseline at 12 weeks served as the primary end point. Results At 12 weeks, the mean declines in SCORAD for the entire study population were 13.8 ± 2.7 in the fezakinumab arm and 8.0 ± 3.1 in the placebo arm (P = .134). In the severe AD patient subset (with a baseline SCORAD of ≥50), SCORAD decline was significantly stronger in the drug-treated patients than placebo-treated patients at 12 weeks (21.6 ± 3.8 vs 9.6 ± 4.2, P = .029) and 20 weeks (27.4 ± 3.9 vs 11.5 ± 5.1, P = .010). At 12 weeks, improvements in body surface area involvement in the entire population were significantly stronger in the drug-treated than placebo-treated patients (12.4% ± 2.4 vs 6.2% ± 2.7; P = .009), and in the severe AD subset, the decline in Investigator Global Assessment was significantly higher in the drug-treated than placebo-treated patients (0.7 ± 0.2 vs 0.3 ± 0.1; P = .034). All scores showed progressive improvements after last dosing (10 weeks) until end of study (20 weeks). Common adverse events were upper respiratory tract infections. Limitations The limited sample size and lack of assessment with Eczema Area and Severity Index and a pruritus numerical rating scale were limiting factors. Significance was primarily obtained in severe AD. Conclusion Fezakinumab was well-tolerated, with sustained clinical improvements after last drug dosing.

Human cytomegalovirus (CMV) infection is a substantial cause of morbidity and mortality in immunocompromised hosts and globally is one of the most important congenital infections. The nucleoside analogue ganciclovir (GCV), which requires initial phosphorylation by the viral UL97 kinase, is the mainstay for treatment. To date, CMV decay kinetics during GCV therapy have not been extensively investigated and its clinical implications not fully appreciated. We measured CMV DNA levels in the blood of 92 solid organ transplant recipients with CMV disease over the initial 21 days of ganciclovir therapy and identified four distinct decay patterns, including a new pattern exhibiting a transient viral rebound (Hump) following initial decline. Since current viral dynamics models were unable to account for this Hump profile, we developed a novel multi-level model, which includes the intracellular role of UL97 in the continued activation of ganciclovir, that successfully described all the decline patterns observed. Fitting the data allowed us to estimate ganciclovir effectiveness in vivo (mean 92%), infected cell half-life (mean 0.7 days), and other viral dynamics parameters that determine which of the four kinetic patterns will ensue. An important clinical implication of our results is that the virological efficacy of GCV operates over a broad dose range. The model also raises the possibility that GCV can drive replication to a new lower steady state but ultimately cannot fully eradicate it. This model is likely to be generalizable to other anti-CMV nucleoside analogs that require activation by viral enzymes such as UL97 or its homologues.

The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) with mammography (MG) and combined CESM + MG in terms of detection and size estimation of histologically proven breast cancers in order to assess the potential to reduce radiation exposure. A total of 118 patients underwent MG and CESM and had final histological results. CESM was performed as a bilateral examination starting 2 min after injection of iodinated contrast medium. Three independent blinded radiologists read the CESM, MG, and CESM + MG images with an interval of at least 4 weeks to avoid case memorization. Sensitivity and size measurement correlation and differences were calculated, average glandular dose (AGD) levels were compared, and breast densities were reported. Fisher's exact and Wilcoxon tests were performed. A total of 107 imaging pairs were available for analysis. Densities were ACR1: 2, ACR2: 45, ACR3: 42, and ACR4: 18. Mean AGD was 1.89 mGy for CESM alone, 1.78 mGy for MG, and 3.67 mGy for the combination. In very dense breasts, AGD of CESM was significantly lower than MG. Sensitivity across readers was 77.9 % for MG alone, 94.7 % for CESM, and 95 % for CESM + MG. Average tumor size measurement error compared to postsurgical pathology was -0.6 mm for MG, +0.6 mm for CESM, and +4.5 mm for CESM + MG (p < 0.001 for CESM + MG vs. both modalities). CESM alone has the same sensitivity and better size assessment as CESM + MG and was significantly better than MG with only 6.2 % increase in AGD. The combination of CESM + MG led to systematic size overestimation. When a CESM examination is planned, additional MG can be avoided, with the possibility of saving up to 61 % of radiation dose, especially in patients with dense breasts.

Renal transplant recipients (RTR) are considered at high risk for influenza-associated complications due to immunosuppression. The efficacy of standard influenza vaccination in RTRs is unclear. Hence, we evaluated activation of the adaptive immunity by the pandemic influenza A(H1N1) 2009 (A(H1N1)pdm09) vaccine in RTRs as compared to healthy controls. To determine cross-reactivity and/or bystander activation, seasonal trivalent influenza vaccine and tetanus/diphteria toxoid (TT/DT) vaccine-specific T cells along with allospecific T cells were quantified before and after A(H1N1)pdm09 vaccination. Vaccination-induced alloimmunity was additionally determined by quantifying serum creatinine and proinflammatory protein IP-10. Contrary to healthy controls, RTRs required a booster vaccination to achieve seroconversion (13.3 % day 21; 90 % day 90). In contrast to humoral immunity, sufficient A(H1N1)pdm09-specific T-cell responses were mounted in RTRs already after the first immunization with a magnitude comparable with healthy controls. Interestingly, vaccination simultaneously boosted T cells reacting to seasonal flu but not to TT/DT, suggesting cross-activation. No alloimmune effects were recorded. In conclusion, protective antibody responses required booster vaccination. However, sufficient cellular immunity is established already after the first vaccination, demonstrating differential kinetics of humoral and cellular immunity.

Immunosenescence is a hallmark of the aging immune system and is considered the main cause of a reduced vaccine efficacy in the elderly. Although γδ T cells can become activated by recombinant influenza hemagglutinin, their age- related immunocompetence during a virus-induced immune response has so far not been investigated. In this study we evaluate the kinetics of γδ T cells after vaccination with the trivalent 2011/2012 northern hemisphere seasonal influenza vaccine. We applied multi-parametric flow cytometry to a cohort of 21 young (19–30 years) and 23 elderly (53–67 years) healthy individuals. Activated and proliferating γδ T cells, as identified by CD38 and Ki67 expression, were quantified on the days 0, 3, 7, 10, 14, 17, and 21. We observed a significantly lower number of activated and proliferating γδ T cells at baseline and following vaccination in elderly as compared to young individuals. The kinetics changes of activated γδ T cells were much stronger in the young, while corresponding changes in the elderly occurred slower. In addition, we observed an association between day 21 HAI titers of influenza A and the frequencies of Ki67+ γδ T cells at day 7 in the young. In conclusion, aging induces alterations of the γδ T cell response that might have negative implications for vaccination efficacy.

Background: Antiviral treatment of chronic hepatitis C is not invariably successful costly and associated with serious side effects and therefore should be indicated only when the chances of benefitting patients exceed the potential risks. The suppressor of cytokine signalling (SOCS) family members have been suggested to affect the rate of virological response to therapy but the published evidence is conflicting. Methods: We measured the intrahepatic SOCS1 SOCS3 and SOCS7 mRNA levels in 107 chronic hepatitis C patients and assessed their clinical and histological correlates with the virological response to therapy and with some factors known for affecting treatment outcome. Results: By multivariate analysis SOCS1 SOCS3 and SOCS7 mRNA levels were not associated with rapid or sustained virological response. Similarly no association was found between the levels of any intrahepatic SOCS mRNA and those of the homeostasis model assessment of insulin resistance. Conversely SOCS1 (OR 2.185 95 CI 1.223 3.906 P=0.0083) and SOCS3 (OR 40.601 95 CI 2.357 699.25 P=0.0108) mRNA level (but not SOCS7) together with age (OR 1.156 95 CI 1.049 1.275 P=0.0036) were independently associated with cirrhosis. Conclusions: Intrahepatic SOCS1 SOCS3 and SOCS7 mRNA levels do not predict virological response to therapy in chronic hepatitis C. The association between SOCS1 SOCS3 and cirrhosis warrants further study. © 2012 John Wiley Sons A/S.

Hepatitis C viral (HCV) kinetics after initiation of interferon-based therapy provide valuable insights for understanding virus pathogenesis, evaluating treatment antiviral effectiveness and predicting treatment outcome. Adverse effects of liver fibrosis and steatosis on sustained virological response have been frequently reported, yet their impacts on the early viral kinetics remain unclear. In this study, associations between histology status and early viral kinetics were assessed in 149 HCV genotype 1-infected patients treated with pegylated interferon alfa-2a and ribavirin (DITTO trial). In multivariate analyses adjusted for critical factors such as IL28B genotype and baseline viral load, presence of significant fibrosis (Ishak stage > 2) was found to independently reduce the odds of achieving an initial reduction (calculated from day 0 to day 4) in HCV RNA of ≥2 logIU/mL (adjusted OR 0.03, P = 0.004) but was not associated with the second-phase slope of viral decline (calculated from day 8 to day 29). On the contrary, presence of liver steatosis was an independent risk factor for not having a rapid second-phase slope, that is, ≥0.3 logIU/mL/week (adjusted OR 0.22, P = 0.012) but was not associated with the first-phase decline. Viral kinetic modelling theory suggests that significant fibrosis primarily impairs the treatment antiviral effectiveness in blocking viral production by infected cells, whereas the presence of steatosis is associated with a lower net loss of infected cells. Further studies will be necessary to identify the biological mechanisms underlain by these findings.

The anti-malaria drug artesunate has been shown to be an effective inhibitor of cytomegalovirus (CMV) in vitro , in an experimental animal model, and in a recent single-case clinical use. In this first case-series of 6 stem cell transplant recipients who received preemptive artesunate treatment for CMV infection, we have examined the viral kinetics following institution of artesunate, and employed first-phase viral kinetics studies to calculate its antiviral effectiveness. Two patients demonstrated a rapid 0.8–2.1 log viral load decline by 7 days, with a viral decay half-live of 0.9–1.9 days. Four patients demonstrated a continued yet stalled viral growth slope during treatment. No adverse events were noted in treatment courses of up to 28 days. Overall, a divergent antiviral efficacy was revealed, ranging from 43% to 90%, which appeared to be primarily dependent on the virus baseline growth dynamics. Further dose escalation studies are needed to examine the role of artesunate in the treatment of CMV infection in the transplantation setting.

Summary. The objective of this study was to find very early viral kinetic markers to predict nonresponse to hepatitis C virus (HCV) therapy in a group of human immunodeficiency virus (HIV)/HCV-coinfected patients. Twenty-six patients (15 HCV genotype-1 and 11 genotype-3) were treated with a 48-week regimen of peginterferon-alfa-2a (PEG-IFN) (180 μg/week) and weight-based ribavirin (11 mg/kg/day). Samples were collected at baseline; 4, 8, 12, 18, 24, 30, 36 and 42 h; days 2, 3, 4, 7, 8, 15, 22, 29, 43 and 57 then weekly and monthly. Five patients discontinued treatment. Seven patients (27%) achieved a sustained virological response (SVR). Nadir HCV RNA levels were observed 1.6 ± 0.3 days after initiation of therapy, followed by a 0.3- to 12.9-fold viral rebound until the administration of the second dose of PEG-IFN, which were not associated with SVR or HCV genotype. A viral decline

A longitudinal discriminant analysis is applied to build predictive models based on repeated measurements of serum hepatitis C virus RNA. These models are evaluated through the partial area under the receiver operating curve index (PA index) and, the final selection of the best model is based on cross-validated estimates of the PA index. Models are compared by building 95% bootstrap confidence interval for the difference in PA index between two models. Data from a randomised trial, in which chronic HCV patients were enrolled, are used to illustrate the application of the proposed method to predict treatment outcome.

The combination of ribavirin and pegylated interferon is used to treat hepatitis C, but it achieves viral clearance in 19%–52% of patients infected with hepatitis C virus (HCV) genotype 1 and in 76%–80% of patients infected with HCV genotypes 2 and 3 [1–3]. Such host factors as race and infection with human immunodeficiency virus (HIV) have been associated with a poor response to treatment [3–5]. The optimal clinical outcome—a sustained virologic response (SVR)—is closely associated with an early response (ER) at week 4 of treatment [6]. Thus, early changes in the HCV level can give insights as to why some groups have a poor response to anti-HCV treatment. Viral kinetics studies [7–11] have shown a lower effectiveness of interferon in black Americans, compared with white Americans [8], and this lower effectiveness is a possible explanation for the lower SVR encountered among blacks [3]. Similarly, treatment trials involving HIV/HCV-infected patients have also demonstrated a lower SVR [4, 5]. However, whether the presence of HIV alters the early viral kinetics of HCV during interferon therapy remains unclear. Viral genotype is another important determinant of responsiveness: HCV genotype 1 is less responsive than HCV genotypes 2 and 3, which demonstrate first- and second-phase decreases faster than those observed for genotype 1 [9, 11]. The different viral clones observed within an individual have different pharmacodynamic responses to exogenous interferon. Nonstructural 5A (NS5A) is a viral protein that has been most associated with interferon responsiveness, especially the interferon sensitivity–determining region. NS5A binds and inhibits the protein kinase R–binding domain (PKRbd), attenuating the kinase action in interferon-mediated antiviral responses in a manner that varies among viral quasispecies [9, 11–14]. It has been suggested that variation from an interferon-resistant prototype viral sequence for genotype 1b (ie, HCV-J) is associated with greater likelihood of a response to therapy; however, this suggestion remains controversial [15–22]. We undertook a thorough reexamination of NS5A to determine how variations in this region might contribute to an ER to anti-HCV therapy. We hypothesized that viral factors, such as the composition of NS5A quasispecies and the dynamic changes in NS5A quasispecies during the first week of therapy, may be associated with the virologic response at week 4 (ie, an ER) and an eventual SVR.

Primary human immunodeficiency virus (HIV) infection is characterized by an initial exponential increase of viral load in peripheral blood reaching a peak, followed by a rapid decline to the viral setpoint. Although the target-cell-limited model can account for part of the viral kinetics observed early in infection [Phillips, 1996. Reduction of HIV concentration during acute infection: independence from a specific immune response. Science 271 (5248), 497–499], it frequently predicts highly oscillatory kinetics after peak viremia, which is not typically observed in clinical data. Furthermore, the target-cell-limited model is unable to predict long-term viral kinetics, unless a delayed immune effect is assumed [Stafford et al., 2000. Modeling plasma virus concentration during primary HIV infection. J. Theor. Biol. 203 (3), 285–301]. We show here that extending the target-cell-limited model, by implementing a saturation term for HIV-infected cell loss dependent upon infected cell levels, is able to reproduce the diverse observed viral kinetic patterns without the assumption of a delayed immune response. Our results suggest that the immune response may have significant effect on the control of the virus during primary infection and may support experimental observations that an anti-HIV immune response is already functional during peak viremia.

Background Telaprevir (TVR) is a hepatitis C virus (HCV) NS3.4A protease inhibitor that has exhibited antiviral activity in patients with HCV genotype 1 infection. The viral dynamics in patients dosed with TVR were compared with those reported for patients treated with interferon (IFN). Methods The dynamics of wild-type HCV genotype 1 in patients dosed with TVR monotherapy ( n=36) and TVR plus pegylated interferon (PEG-IFN)-α2a ( n=8) were quantified using a biphasic viral dynamic model. Results Patients dosed with either TVR monotherapy or TVR plus PEG-IFN-α2a had median first and second phase decreases of 12 per day and 1.1 per day, respectively. The second phase decrease was approximately 10-fold higher than reported values for IFN-based treatments ( P10. In patients dosed with TVR mono-therapy, increased TVR dosage of the same schedule was related to better blockage. Conclusions These results suggested that TVR-based regimens for chronic HCV infection will lead to an early and more rapid viral decrease that could potentially result in higher sustained viral response rates as well as offer the potential for a reduced duration of treatment.

Understanding the immune response after vaccination against new influenza strains is highly important in case of an imminent influenza pandemic and for optimization of seasonal vaccination strategies in high risk population groups, especially the elderly. Models predicting the best sero-conversion response among the three strains in the seasonal vaccine were recently suggested. However, these models use a large number of variables and/or information post- vaccination. Here in an exploratory pilot study, we analyzed the baseline immune status in young (

Background & Aims: The second slope of viral decline induced by interferon treatment has been suggested to be influenced mainly by the hepatitis C virus (HCV)-specific T-cell response; however, this hypothesis needs to be validated by results derived from experimental studies. Methods: To address this issue, the HCV-specific T-cell response of 32 genotype-1–infected patients of the 270 patients enrolled in the dynamically individualized treatment of hepatitis C infection and correlates of viral/host dynamics phase III, open-label, randomized, multicenter trial was studied in relation to viral kinetics and treatment outcome. Results: Greater proliferative responses by HCV-specific CD8 cells were found before treatment in patients with a fast viral decline and with a sustained viral response. However, no significant improvement of HCV-specific CD8 responses was observed in the first weeks of therapy in both rapid viral responder and non–rapid viral responder patients. A mild enhancement of proliferative T-cell responses and a partial restoration of the cytotoxic T-cell potential was expressed only late during treatment, likely favored by HCV clearance. Conclusions: Early restoration of an efficient T-cell response does not seem to be an essential requirement for a rapid viral decline in the first weeks of treatment. However, patients presenting a better HCV-specific CD8 cell proliferative potential at baseline are more likely to present a rapid and sustained viral response. Therefore, future treatment protocols should consider the development of strategies aimed at improving HCV-specific T-cell responses.

OBJECTIVE The major antiviral effect of interferon (IFN)-alpha on hepatitis C virus (HCV) is blocking of virion production from infected cells. We now investigate the previously unknown mechanism of action of IFN-alpha against HIV. METHODS HIV kinetics in parallel to HCV kinetics and IFN pharmacokinetics during pegylated-IFN-alpha-2b (1.5 microg/Kg q.w., PEG-IFN) and ribavirin (1-1.2 g daily) treatment in nine HIV patients co-infected with HCV genotype 1 were analyzed. In vivo modeling predictions of suppression of HIV replication by PEG-IFN in CD8-depleted peripheral blood mononuclear cells were verified by in vitro experiments. RESULTS HCV and HIV show different viral decline patterns after administration of PEG-IFN. Unlike the bi-phasic decline shown by HCV, HIV shows a slow continuous decline during the first week, with no rebound when PEG-IFN levels decline. Fitting of HIV kinetics with known half-lives of free virus and infected cells indicates that the major effect of IFN on HIV is to block de novo infection rather than to block virion production. The magnitude of the antiviral effect is similar (mean 1.1 log10 decline at 7 days) to those of direct anti-HIV drugs, but shows an inverse correlation with baseline viremia. In vitro studies show that preincubation with IFN renders a suppression of HIV replication superior to that of treatment postinfection, thus corroborating the mathematical analysis in vivo. CONCLUSION The complimentary antiviral properties of IFN-alpha and antiretroviral therapy suggest a role for pharmacokinetically improved formulations of IFN as part of salvage therapy for HIV-infected individuals.

It is well known that the mathematical models provide very important information for the research of human immunodeficiency virus-type 1 and hepatitis C virus (HCV). However, the infection rate of almost all mathematical models is linear. The linearity shows the simple interaction between the T cells and the viral particles. In this paper, we consider the classical mathematical model with saturation response of the infection rate. By stability analysis we obtain sufficient conditions on the parameters for the global stability of the infected steady state and the infection-free steady state. We also obtain the conditions for the existence of an orbitally asymptotically stable periodic solution. Numerical simulations are presented to illustrate the results.

Liver steatosis is highly prevalent in chronic hepatitis C virus (HCV) infection, especially in patients infected with genotype 3 virus, but its significance for the outcome of antiviral treatment is not fully understood. We have monitored steatosis in liver biopsies from 231 patients with chronic HCV infection who received pegylated recombinant interferon-alpha and ribavirin in a phase III study (DITTO trial). The degree of steatosis, along with relevant metabolic parameters, was correlated with the early disappearance of virus and with the final outcome of treatment. Our data suggest that the presence of steatosis impairs the early reduction of viral load during treatment in patients infected with HCV genotype 3 and non-3. Steatosis negatively affected the final outcome of treatment mainly in patients infected with HCV genotype non-3 virus. Based on these findings, we propose that interventions aiming at reducing hepatic steatosis prior to the onset of antiviral therapy may be of benefit to patients infected with HCV of the non-3 genotypes. Patients infected with genotype 3, on the other hand, should be offered early antiviral treatment.

Albumin-interferon-alpha (IFN-alpha) is a novel 85.7-kDa recombinant protein consisting of IFN-alpha that is genetically fused to human serum albumin. In this Phase I/II, multicentre, open-label study, we evaluated the safety and tolerability, pharmacokinetics and pharmacodynamics of albumin-IFN-alpha in IFN-alpha-experienced patients with chronic hepatitis C. Albumin-IFN-alpha was administered in 22 escalating doses (7-900 microg) in a single injection or in two injections 14 days apart. In the 119 patients studied, there were no discontinuations because of adverse events, and albumin-IFN-alpha had a favourable safety profile at doses up to 900 microg. The most common adverse events were headache (56%), fatigue (52%), injection site erythema (38%), arthralgias (32%) and pyrexia (27%). Reduced clearance resulted in a mean elimination half-life of 159 h, which supports dosing at 2- to 4-week intervals. Induction of the IFN-specific gene OAS1 was maintained for > or = 28 days following a single injection of albumin-IFN-alpha at doses of > or = 40 microg. Dose-dependent antiviral activity was observed in this IFN-alpha-experienced study population. Antiviral activity of > or = 1.0-log reductions in HCV RNA was observed in 47% (37/78) of patients in the 120- to 900-microg cohorts and in 59% (16/27) in the 400- to 900-microg double-injection cohorts. These results support further clinical studies of albumin-IFN-alpha for the treatment of patients with chronic hepatitis C.

Plasma from 173 patients with HCV genotype 1 infection was analyzed for IP-10 levels prior to treatment with pegylated interferon-α-2a and ribavirin. Significantly lower IP-10 levels were observed in patients achieving a rapid viral response (RVR) (P < .0001), even in those with body mass index (BMI) ≥ 25 kg/m2 (P = .004) and with baseline viral load ≥ 2 million IU/mL (P = .001). Similarly, significantly lower IP-10 levels were observed in patients obtaining a sustained viral response (SVR) (P = .0002), including those having higher BMI (P < .05), higher viral load (P = .0005), and both higher BMI and viral load (P < .03). In multivariate logistic regression analyses, a low IP-10 value was independently predictive of both RVR and SVR. A baseline cutoff IP-10 value of 600 pg/mL yielded a negative predictive value (NPV) of 79% (19/24) for all genotype 1–infected patients, which was comparable with that observed using a reduction in HCV-RNA by at least 2 logs after 12 weeks of therapy (NPV 86%; 19/22); by combining the two, 30 of 38 patients (NPV 79%) potentially could have been spared unnecessary therapy. In patients having both higher BMI and viral load, cut-off levels of 150 and 600 pg/mL yielded a positive predictive value (PPV) of 71% and NPV of 100%, respectively. In conclusion, pretreatment IP-10 levels predict RVR and SVR in patients infected with HCV genotype 1, even in those with higher BMI and viral load. A substantial proportion of the latter patients may achieve SVR in spite of unfavorable baseline characteristics if their pretreatment IP-10 level is low. Thus, pretreatment IP-10 analysis may prove helpful in decision-making regarding pharmaceutical intervention. (HEPATOLOGY 2006;44:1617–1625.)

Background & Aims: Although hepatitis C virus kinetics and immune determinants during primary infection have been described, the virus-host interplay is not fully understood. We used mathematical modeling to elucidate and quantify virus-host dynamics. Methods: Ten chimpanzees were infected intrahepatically with H77-RNA (n = 3) or intravenously with infected serum. Blood samples were taken 1–3 times per week for 6 months. A new model was fitted to the observed HCV RNA and alanine aminotransferase (ALT) kinetics. Results: After infection, viral levels increased in a biphasic manner with a transient decline in between. This can be explained by a partial block (mean, 91%) of virion production, possibly due to an endogenous type I interferon response. After reaching maximum levels, a long viral plateau (mean, 6.1 log cp/mL) can be explained by blind homeostasis and lack of susceptible cells. Modest elevations in ALT levels (21–93 IU/L) were concurrently observed, indicating a shorter half-life of infected versus noninfected hepatocytes (mean ratio, 2.6). Following the ALT flare, viral titers rapidly declined to a lower (mean, 4.5 log cp/mL; n=6) or undetectable level (n = 4). This decline is compatible with increased cell death (mean minimal estimate half-life, 28.7 days) and noncytolytic clearance (mean maximal estimate half-life, 24.1 days) of infected cells. Conclusions: Our results quantify virus-host dynamics during primary HCV infection and suggest that endogenous type I interferon slows virus production in the early acute phase. Partial or effective virus control correlates with the half-life of infected cells regulated by both cytolytic and noncytolytic mechanisms.

Background & Aims : In the patients with chronic hepatitis C, the addition of ribavirin to interferon (IFN)-α significantly increases the virologic responses. Our aim was to assess the antiviral action of ribavirin on hepatitis C virus (HCV) as a function of ribavirin pharmacokinetics and to evaluate the influence of this antiviral effect on IFN-α efficacy. Methods : Forty-five patients with chronic hepatitis C (genotype 1b) received various schedules of IFN-α and/or ribavirin administration. Frequent blood sampling was performed for HCV RNA kinetics and ribavirin pharmacokinetics assessment. Results : Ribavirin monotherapy induced a significant, moderate, early, and transient viral load decrease in approximately half of the patients. The occurrence of this effect was associated with longer ribavirin clearance half-lives and higher serum ribavirin concentrations. Ribavirin antiviral effect partly reduced the rebound preceding the second IFN-α injection in patients receiving standard IFN-α 3 times per week plus ribavirin. The magnitude of the rebound was inversely related to ribavirin concentrations. These patients subsequently experienced a slow, but significant, second slope of viral decrease and cleared HCV RNA. The addition of ribavirin to daily IFN-α monotherapy did not have any impact on the second phase of viral decline. Conclusions : Ribavirin exerts a significant, moderate, and transient antiviral effect in a significant proportion of patients with chronic hepatitis C. The antiviral effect of ribavirin correlates with ribavirin pharmacokinetics and is partly responsible for the improved efficacy of the combination of standard IFN-α and ribavirin compared with IFN-α monotherapy by increasing the incidence of the initial response.

To study determinants of clinical outcome following HCV infection, viral kinetics, immune events, and intrahepatic cytokine markers were compared in 10 naive chimpanzees. Four of the animals cleared HCV; 6 developed persistent infections. All animals developed similar acute infections with increasing viremia from 1 to 2 weeks, followed by alanine aminotransferase (ALT) elevations and seroconversion. This viremia pattern consisted of a biphasic increase, a rapid slope (mean doubling time [t2] = 0.5 days) followed by a slower slope after the second week (t2 = 7.5 days). This slowing of virus replication correlated in all animals with increased intrahepatic 2′5′ oligoadenylate synthetase 1 (2OAS-1) messenger RNA (mRNA) levels and was independent of disease outcome. An effective control of virus replication was observed following increases in intrahepatic interferon γ (IFN-γ) mRNA and ALT levels. Although this control was associated in all animals with a 2-log decrease in virus titer, the timing occurred approximately 2 weeks later in the chronic group (P < .05). Additionally, while cleared infections were characterized by a continual decrease in virus titer, the titers in the persistent infections reached a steady state level of 104 to 105 RNA copies/mL. This inability of the immune response to sustain viral clearance in the persistent infections was associated with a reduced intrahepatic CD3e and monocyte-induced protein 1α (MIP-1α) mRNA induction. In conclusion, these data indicate that, regardless of outcome, chimpanzees generate responses that control HCV replication during the early and late acute phase. However, the pathogenesis of HCV may be determined by a more rapid onset of the induced response and the cell population that migrates to the liver. (HEPATOLOGY 2004;39:1709–1720.)