Endotoxemia Associated with Liver Disease Correlates with Systemic Inflammation and T Cell Exhaustion in Hepatitis C Virus Infection.

Both acute and chronic hepatitis C virus (HCV) infections are characterized by inflammation. HCV and reduced liver blood filtration contribute to inflammation; however, the mechanisms of systemic immune activation and dysfunction as a result of HCV infection are not clear. We measured circulating inflammatory mediators (IL-6, IP10, sCD163, sCD14), indices of endotoxemia (EndoCab, LBP, FABP), and T cell markers of exhaustion and senescence (PD-1, TIGIT, CD57, KLRG-1) in HCV-infected participants, and followed a small cohort after direct-acting anti-viral therapy. IL-6, IP10, Endocab, LBP, and FABP were elevated in HCV participants, as were T cell co-expression of exhaustion and senescence markers. We found positive associations between IL-6, IP10, EndoCab, LBP, and co-expression of T cell markers of exhaustion and senescence. We also found numerous associations between reduced liver function, as measured by plasma albumin levels, and T cell exhaustion/senescence, inflammation, and endotoxemia. We found positive associations between liver stiffness (TE score) and plasma levels of IL-6, IP10, and LBP. Lastly, plasma IP10 and the proportion of CD8 T cells co-expressing PD-1 and CD57 decreased after initiation of direct-acting anti-viral therapy. Although associations do not prove causality, our results support the model that translocation of microbial products, resulting from decreased liver blood filtration, during HCV infection drives chronic inflammation that results in T cell exhaustion/senescence and contributes to systemic immune dysfunction.

Low rates of antibiotics prescribed during telehealth primary-care visits persisted during the coronavirus disease 2019 (COVID-19) pandemic.

For primary care clinics at a Veterans' Affairs (VA) medical center, the shift from in-person to telehealth visits during the coronavirus disease 2019 (COVID-19) pandemic was associated with low rates of antibiotic prescription. Understanding contextual factors associated with antibiotic prescription practices during telehealth visits may help promote antibiotic stewardship in primary care settings.

Red Cell Distribution Width and Absolute Lymphocyte Count Associate With Biomarkers of Inflammation and Subsequent Mortality in Rheumatoid Arthritis.

OBJECTIVE: Morbidity and mortality in rheumatoid arthritis (RA) is partly mitigated by maintaining immune and hematologic homeostasis. Identification of those at risk is challenging. Red cell distribution width (RDW) and absolute lymphocyte count (ALC) associate with cardiovascular disease (CVD) and mortality in the general population, and with disease activity in RA. How these variables relate to inflammation and mortality in RA was investigated. METHODS: In a retrospective single Veterans Affairs (VA) Rheumatology Clinic cohort of 327 patients with RA treated with methotrexate (MTX)+/- a tumor necrosis factor (TNF) inhibitor (TNFi), we evaluated RDW and ALC before and during therapy and in relation to subsequent mortality. Findings were validated in a national VA cohort (n = 13,914). In a subset of patients and controls, we evaluated inflammatory markers. RESULTS: In the local cohort, high RDW and low ALC prior to MTX treatment was associated with subsequent mortality over 10 years (both P < 0.001). The highest mortality was observed in those with both high RDW and low ALC. This remained after adjusting for age and comorbidities and was validated in the national RA cohort. In the immunology cohort, soluble and cellular inflammatory markers were higher in patients with RA than in controls. ALC correlated with age, plasma TNF receptor II, natural killer HLA-DR mean fluorescence intensity, and CD4CM/CD8CM HLA-DR/CD38%, whereas RDW associated with age and ALC. MTX initiation was followed by an increase in RDW and a decrease in ALC. TNFi therapy added to MTX resulted in an increase in ALC. CONCLUSION: RDW and ALC before disease-modifying antirheumatic drug therapy are associated with biomarkers of monocyte/macrophage inflammation and subsequent mortality. The mechanistic linkage between TNF signaling and lymphopenia found here warrants further investigation.

Markers of T Cell Exhaustion and Senescence and Their Relationship to Plasma TGF-ß Levels in Treated HIV+ Immune Non-responders.

Background: Immune non-responders (INR) are HIV+, ART-controlled (>2 yrs) people who fail to reconstitute their CD4 T cell numbers. Systemic inflammation and markers of T cell senescence and exhaustion are observed in INR. This study aims to investigate T cell senescence and exhaustion and their possible association with soluble immune mediators and to understand the immune profile of HIV-infected INR. Selected participants were <50 years old to control for the confounder of older age. Methods: Plasma levels of IL-6, IP10, sCD14, sCD163, and TGF-ß and markers of T cell exhaustion (PD-1, TIGIT) and senescence (CD57, KLRG-1) were measured in ART-treated, HIV+ participants grouped by CD4 T cell counts (n = 63). Immune parameters were also measured in HIV-uninfected, age distribution-matched controls (HC; n = 30). Associations between T cell markers of exhaustion and senescence and plasma levels of immune mediators were examined by Spearman rank order statistics. Results: Proportions of CD4 T cell subsets expressing markers of exhaustion (PD-1, TIGIT) and senescence (CD57, KLRG-1) were elevated in HIV+ participants. When comparing proportions between INR and IR, INR had higher proportions of CD4 memory PD-1+, EM CD57+, TEM TIGIT+ and CD8 EM and TEM TIGIT+ cells. Plasma levels of IL-6, IP10, and sCD14 were elevated during HIV infection. IP10 was higher in INR. Plasma TGF-ß levels and CD4 cycling proportions of T regulatory cells were lower in INR. Proportions of CD4 T cells expressing TIGIT, PD-1, and CD57 positively correlated with plasma levels of IL-6. Plasma levels of TGF-ß negatively correlated with proportions of TIGIT+ and PD-1+ T cell subsets. Conclusions: INR have lower levels of TGF-ß and decreased proportions of cycling CD4 T regulatory cells and may have difficulty controlling inflammation. IP10 is elevated in INR and is linked to higher proportions of T cell exhaustion and senescence seen in INR.

Hepatitis C Virus (HCV) Direct-Acting Antiviral Therapy in Persons With Human Immunodeficiency Virus-HCV Genotype 1 Coinfection Resulting in High Rate of Sustained Virologic Response and Variable in Normalization of Soluble Markers of Immune Activation.

BACKGROUND: Hepatitis C virus (HCV) direct-acting antivirals are highly effective. Less is known about changes in markers of immune activation in persons with human immunodeficiency virus (HIV) in whom a sustained virologic response (SVR) is achieved. METHODS: We conducted a nonrandomized clinical trial of 12 or 24 weeks of paritaprevir-ritonavir-ombitasvir plus dasabuvir (PrOD) with or without ribavirin in persons with HCV-1/HIV coinfection suppressed with antiretroviral therapy. Plasma HCV, soluble CD14 (sCD14), interferon-inducible protein 10, soluble CD163 (sCD163), interleukin 6 (IL-6), interleukin 18, monocyte chemoattractant protein (MCP-1), autotaxin (ATX), and Mac2-binding protein (Mac2BP) were measured over 48 weeks. RESULTS: Participants were treated with PrOD for 12 (n = 9) or 24 (n = 36) weeks; the SVR rate at 12 weeks was 93%. At baseline, cirrhosis was associated with higher ATX and MCP-1, female sex with higher ATX and IL-6, older age with higher Mac2BP, higher body mass index with higher ATX, and HIV-1 protease inhibitor use with higher sCD14 levels. In those with SVR, interferon-inducible protein 10, ATX, and Mac2BP levels declined by week 2, interleukin 18 levels declined by the end of treatment, sCD14 levels did not change, and sCD163, MCP-1, and IL-6 levels changed at a single time point. CONCLUSIONS: During HIV/HCV coinfection, plasma immune activation marker heterogeneity is in part attributable to age, sex, cirrhosis, body mass index, and/or type of antiretroviral therapy. HCV treatment with paritaprevir-ritonavir-ombitasvir plus dasabuvir is highly effective and is associated with variable rate and magnitude of decline in markers of immune activation. CLINICAL TRIALS REGISTRATION: NCT02194998.