Elevated Foxp3+ double-negative T cells are associated with disease progression during HIV infection

Association between gut microbiota in HIV-infected patients and immune reconstitution following antiretroviral therapy (ART)

BACKGROUND

This study aims to examine the potential link between incomplete immune reconstitution following ART treatment and gut microbiota dysbiosis.

METHODS

We collected clinical data and fecal samples from 50 HIV patients undergoing ART and 30 untreated patients. Based on the observed immune function reconstruction, we further categorized the ART(+) group into a responder group (n = 30) and a non-responder group (n = 20). The gut microbiota composition differences were assessed using Alpha diversity and Beta diversity analysis, while differential genera were identified through linear discriminant analysis effect size (LEfSe). Subsequently, functional disparities in the gut microbiota were investigated using PICRUSt2 and metagenomeSeq software.

RESULTS

The results of Alpha diversity and Beta diversity revealed significant differences in the composition of gut microbiota among the three groups. Differential genus analysis identified Morganella as an exclusive genus present only in the Non-responder group, exhibiting a significantly higher relative abundance. Correlation analysis demonstrated a positive association between Morganella and LDL levels. The CAZY analysis revealed that glycosyltransferase 25 (GT25) was significantly expressed in the Non-responder group, whereas it was either undetectable or exhibited extremely low expression levels in both the Responder group and the ART(-) group. Importantly, the correlation analysis indicated a positive association between Morganella and GT25 secretion.

CONCLUSIONS

The ecological imbalance of Morganella might be associated with incomplete immune reconstitution following ART, potentially mediated by GT25 secretions. Consequently, Morganella could serve as a promising biomarker for predicting incomplete immune reconstitution in AIDS patients undergoing ART.

Double-Negative T-Cells during Acute Human Immunodeficiency Virus and Simian Immunodeficiency Virus Infections and Following Early Antiretroviral Therapy Initiation

HIV infection significantly affects the frequencies and functions of immunoregulatory CD3+CD4-CD8- double-negative (DN) T-cells, while the effect of early antiretroviral therapy (ART) initiation on these cells remains understudied. DN T-cell subsets were analyzed prospectively in 10 HIV+ individuals during acute infection and following early ART initiation compared to 20 HIV-uninfected controls. In this study, 21 Rhesus macaques (RMs) were SIV-infected, of which 13 were assessed during acute infection and 8 following ART initiation four days post-infection. DN T-cells and FoxP3+ DN Treg frequencies increased during acute HIV infection, which was not restored by ART. The expression of activation (HLA-DR/CD38), immune checkpoints (PD-1/CTLA-4), and senescence (CD28-CD57+) markers by DN T-cells and DN Tregs increased during acute infection and was not normalized by ART. In SIV-infected RMs, DN T-cells remained unchanged despite infection or ART, whereas DN Treg frequencies increased during acute SIV infection and were not restored by ART. Finally, frequencies of CD39+ DN Tregs increased during acute HIV and SIV infections and remained elevated despite ART. Altogether, acute HIV/SIV infections significantly changed DN T-cell and DN Treg frequencies and altered their immune phenotype, while these changes were not fully normalized by early ART, suggesting persistent HIV/SIV-induced immune dysregulation despite early ART initiation.

Host immunity associated with spontaneous suppression of viremia in therapy-naïve young rhesus macaques following neonatal SHIV infection

IMPORTANCE

Despite the advent of highly active anti-retroviral therapy, people are still dying from HIV-related causes, many of whom are children, and a protective vaccine or cure is needed to end the HIV pandemic. Understanding the nature and activation states of immune cell subsets during infection will provide insights into the immunologic milieu associated with viremia suppression that can be harnessed via therapeutic strategies to achieve a functional cure, but these are understudied in pediatric subjects. We evaluated humoral and adaptive host immunity associated with suppression of viremia in rhesus macaques infected soon after birth with a pathogenic SHIV. The results from our study provide insights into the immune cell subsets and functions associated with viremia control in young macaques that may translate to pediatric subjects for the design of future anti-viral strategies in HIV-1-infected infants and children and contribute to an understudied area of HIV-1 pathogenesis in pediatric subjects.