Improved CD4 T cell profile in HIV-infected subjects on maraviroc-containing therapy is associated with better responsiveness to HBV vaccination

Cured HCV patients with suboptimal hepatitis B vaccine response exhibit high self-reactive immune signatures

BACKGROUND AND RATIONALE

Chronic HCV infection induces lasting effects on the immune system despite viral clearance. It is unclear whether certain immune alterations are associated with vaccine responses in cured HCV patients.

APPROACH

Thirteen cured HCV patients received the standard 3-dose hepatitis B vaccine and were followed up at the 0, 1st, 6th, and 7th months (M0, M1, M6, and M7) after the first dose of vaccination. Thirty-three-color and 26-color spectral flow cytometry panels were used for high-dimensional immunophenotyping of the T-cell and B-cell subsets, respectively.

RESULTS

Compared to the healthy controls (HC), 17 of 43 (39.5%) immune cell subsets showed abnormal frequencies in cured HCV patients. Patients with cured HCV were further divided into high responders (HR, n = 6) and nonresponders (NR1, n = 7) based on the levels of hepatitis B surface antibodies at M1. Alterations in cell populations were more significant in NR1. Moreover, we found that high levels of self-reactive immune signatures, including Tregs, TD/CD8, IgD-only memory B, and autoantibodies, were associated with suboptimal hepatitis B vaccine responses.

CONCLUSIONS

Our data suggest that cured HCV patients exhibit persistent perturbations in the adaptive immune system, among which highly self-reactive immune signatures may contribute to a suboptimal hepatitis B vaccine response.

Do Combination Antiretroviral Therapy Regimens for HIV Infection Feature Diverse T-Cell Phenotypes and Inflammatory Profiles?

Immune abnormalities featuring HIV infection persist despite the use of effective combination antiretroviral therapy (cART) and may be linked to the development of noninfectious comorbidities. The aim of the present narrative, nonsystematic literature review is to understand whether cART regimens account for qualitative differences in immune reconstitution. Many studies have reported differences in T-cell homeostasis, inflammation, coagulation, and microbial translocation parameters across cART classes and in the course of triple vs dual regimens, yet such evidence is conflicting and not consistent. Possible reasons for discrepant results in the literature are the paucity of randomized controlled clinical trials, the relatively short follow-up of observational studies, the lack of clinical validation of the numerous inflammatory biomarkers utilized, and the absence of research on the effects of cART in tissues. We are currently thus unable to establish if cART classes and regimens are truly accountable for the differences observed in immune/inflammation parameters in different clinical settings. Questions still remain as to whether an early introduction of cART, specifically in the acute stage of disease, or newer drugs and novel dual drug regimens are able to significantly impact the quality of immune reconstitution and the risk of disease progression in HIV-infected subjects.

Predictive value of plasmacytoid dendritic cells and Toll-like receptor-9 regarding the treatment efficacy of interferon-α in HBeAg-positive chronic hepatitis B patients

Hepatitis B virus (HBV) infection represents a public health threat and a challenge for the medical community. Untimely treatment may lead to liver cirrhosis and even liver cancer. At present, the major treatment for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients includes administration of interferon-α (IFN-α), which has anti-viral and immunomodulatory effects. Plasmacytoid dendritic cells (pDCs) and Toll-like receptor-9 (TLR-9) have important roles in anti-viral therapy. However, their predictive value regarding the efficacy of IFN-α treatment of HBeAg-positive chronic hepatitis B (CHB) patients has remained elusive. A total of 178 patients with CHB and HBeAg-positive status, who had not received any previous anti-HBV treatment, were enrolled in the present study. All patients were treated with IFN-α. HBV DNA load, hepatitis B surface antigen and serum alanine aminotransferase were measured prior to and following 48 weeks of treatment. According to HBV levels, the patients were divided into a response group and non-responders group. To determine the amount of pDCs, blood dendritic cell antigen 2 (BDCA-2)- and immunoglobulin-like transcript 7 (ILT7)-expressing cells in liver biopsies were detected using immunohistochemistry. TLR-9 expression in peripheral blood mononuclear cells was determined by reverse transcription-quantitative PCR. There was no significant difference in the proportion of pDCs (BDCA-2; ILT7) and TLR-9 mRNA expression between the response group and the non-responders group prior to IFN-α treatment. After IFN-α treatment, BDCA-2, ILT7 and TLR-9 mRNA expression was obviously increased in the response group compared with that in the non-responders group (P<0.05). Increased expression of BDCA-2, ILT7 and TLR-9 mRNA was negatively correlated with HBV DNA (P<0.05). Increased levels of pDCs and TLR-9 were negatively correlated with HBV DNA, and were thus capable of predicting the IFN-α treatment response in patients with CHB and HBeAg-positive status.

Effect of homeostatic T-cell proliferation in the vaccine responsiveness against influenza in elderly people

Background

Seasonal influenza virus infection is a significant cause of morbimortality in the elderly. However, there is poor vaccine efficacy in this population due to immunosenescence. We aimed to explore several homeostatic parameters in the elderly that could impact influenza vaccine responsiveness.

Methods

Subjects (> 60 years old) who were vaccinated against influenza virus were included, and the vaccine response was measured by a haemagglutination inhibition (HAI) test. At baseline, peripheral CD4 and CD8 T-cells were phenotypically characterized. Thymic function and the levels of different inflammation-related biomarkers, including Lipopolysaccharide Binding Protein (LBP) and anti-cytomegalovirus (CMV) IgG antibodies, were also measured.

Results

Influenza vaccine non-responders showed a tendency of higher frequency of regulatory T-cells (Tregs) before vaccination than responders (1.49 [1.08–1.85] vs. 1.12 [0.94–1.63], respectively, p = 0.061), as well as higher expression of the proliferation marker Ki67 in Tregs and different CD4 and CD8 T-cell maturational subsets. The levels of inflammation-related biomarkers correlated with the frequencies of different proliferating T-cell subsets and with thymic function (e.g., thymic function with D-dimers, r = − 0.442, p = 0.001).

Conclusions

Age-related homeostatic dysregulation involving the proliferation of CD4 and CD8 T-cell subsets, including Tregs, was related to a limited responsiveness to influenza vaccination and a higher inflammatory status in a cohort of elderly people.

Electronic supplementary material

The online version of this article (10.1186/s12979-019-0154-y) contains supplementary material, which is available to authorized users.

HIV-1-derived exosomal microRNAs miR88 and miR99 promote the release of cytokines from human alveolar macrophages by binding to TLR8

The human monocytic cell line U937 and human alveolar macrophages were used as in vitro models to explore the role of miR88 and miR99 in the chronic abnormal activation of the body caused by human immunodeficiency virus (HIV). The functions and underlying mechanisms of miR88 and miR99 were studied by real-time quantitative polymerase chain reaction, transwell, and chromatin immunoprecipitation (ChIP) assays. HIV-1-infected cells released miR88 and miR99 into the extracellular space through exosomes, and miR88 and miR99 promoted the release of tumor necrosis factor alpha (TNFα), interleukin (IL)-6, and IL-12 by activating inflammatory factors, such as TLR8, on the surface of macrophages. HIV-derived microRNAs miR88 and miR99 performed these functions by binding to TLR8 and stimulating the release of pro-inflammatory factors from macrophages, such as TNFα, IL-6, and IL-12; these factors may be involved in chronic abnormal immune activation induced by HIV infection.