Association between hepatitis B vaccine antibody response and CD4 reconstitution after initiation of combination antiretroviral therapy in HIV-infected persons

Chronic inflammation degrades CD4 T cell immunity to prior vaccines in treated HIV infection

To date, our understanding of how HIV infection impacts vaccine-induced cellular immunity is limited. Here, we investigate inflammation, immune activation and antigen-specific T cell responses in HIV-uninfected and antiretroviral-treated HIV-infected people. Our findings highlight lower recall responses of antigen-specific CD4 T cells that correlate with high plasma cytokines levels, T cell hyperactivation and an altered composition of the T subsets enriched with more differentiated cells in the HIV-infected group. Transcriptomic analysis reveals that antigen-specific CD4 T cells of the HIV-infected group have a reduced expression of gene sets previously reported to correlate with vaccine-induced pathogen-specific protective immunity and further identifies a consistent impairment of the IFNα and IFNγ response pathways as mechanism for the functional loss of recall CD4 T cell responses in antiretroviral-treated people. Lastly, in vitro treatment with drugs that reduce inflammation results in higher memory CD4 T cell IFNγ responses. Together, our findings suggest that vaccine-induced cellular immunity may benefit from strategies to counteract inflammation in HIV infection.

Evaluation of response to hepatitis B virus vaccine in adults with human immunodeficiency virus

INTRODUCTION AND AIM

Viral hepatitis is a serious public health problem. The risk of progression to chronic hepatitis in hepatitis B virus (HBV) infection occurs in 5-10% of adults and is a leading cause of cirrhosis and hepatocellular carcinoma worldwide. Individuals infected with human immunodeficiency virus (HIV) may have coinfection with HBV. The existence of unvaccinated groups represents a significant risk not only individually but also at the community level. The aim of this study was to evaluate HBV vaccine response in adults with HIV infection.

MATERIALS AND METHODS

A retrospective, descriptive study of the cross-sectional type was carried out in an outpatient HIV referral center in southern Brazil. All medical records of adult HIV patients seen during January 2006 to December 2015 were selected. In statistical analysis, a significance level of 5% was used.

RESULTS

Of the 201 patients evaluated with a complete vaccination scheme, 55.72% were males, with a mean age of 43.86±12.68 years. Vaccine response occurred in 80.10% (161/201) of the patients, and it did not correlate with age, CD4+ cell count or viral load.

CONCLUSION

HBV vaccine response in a HIV population was satisfactory, highlighting the importance of vaccination for prevention, cost reduction and better prognosis in preventing HBV/HIV coinfection.

Suboptimal immune recovery during antiretroviral therapy with sustained HIV suppression in sub-Saharan Africa

OBJECTIVE

To assess incidence, determinants and clinical consequences of suboptimal immune recovery in HIV-1 infected adults in sub-Saharan Africa with sustained viral suppression on antiretroviral therapy (ART).

DESIGN

Multicountry prospective cohort.

METHODS

Suboptimal immune recovery was defined as proportions of participants who failed to attain clinically relevant CD4+ cell count thresholds (>200, >350 and >500 cells/μl) despite sustained viral suppression on continuous first-line ART. Participants were censored at the earliest of death, loss to follow-up, last viral load less than 50 copies/ml, or database closure. Determinants of immune recovery were assessed using multivariable Cox regression. We estimated incidence rates of AIDS, pulmonary tuberculosis and all-cause mortality for CD4+ strata.

RESULTS

One thousand, five hundred and ninety-two participants were included; 60% were women, median age was 37 years (IQR 31-43) and median pre-ART CD4+ cell count was 147 cells/μl (IQR 76-215). After 6 years of ART, suboptimal immune recovery at CD4+ cell counts less than 200 cells/μl, less than 350  cells/μl, and less than 500 cells/μl occurred in 7, 27, and 57% of participants, respectively. Compared with participants with CD4+ cell count greater than 500 cells/μl, on-ART incidence rates were 12.5, 4.1, 0.9 times higher for AIDS and 16.9, 3.5, and 2.3 times higher for pulmonary tuberculosis in participants with CD4+ cell count less than 200, 200-349, and 350-499 cells/μl, respectively. All-cause mortality was highest in participants with CD4+ cell count less than 200 cells/μl, and comparable across the higher CD4+ strata. Older age, male sex, and lower pre-ART CD4+ cell count were strongly associated with suboptimal immune recovery.

CONCLUSION

These findings warrant close clinical and laboratory monitoring until adequate immune reconstitution is achieved and support early ART initiation before decline of CD4+ cell count.