Characteristics of blood immune cell profile and their correlation with disease progression in patients infected with HIV-1.

BACKGROUND: Antiretroviral therapy (ART) can reduce viral load in individuals infected with human immunodeficiency virus (HIV); however, some HIV-infected individuals still cannot achieve optimal immune recovery even after ART. Hence, we described the profile of peripheral immune cells and explored the association with disease progression in patients infected with HIV-1. METHODS: Mass cytometry analysis was used to characterize the circulating immune cells of 20 treatment-naïve (TNs), 20 immunological non-responders (INRs), 20 immunological responders (IRs), and 10 healthy controls (HCs). Correlation analysis was conducted between cell subpopulation percentages and indicators including HIV-1 cell-associated (CA)-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio. RESULTS: Global activation, immunosenescence, and exhaustion phenotypes were observed in myeloid cells and T cells from individuals with HIV-1 infection. We also found that specific subsets or clusters of myeloid, CD4+ T, and CD8+ T cells were significantly lost or increased in TN individuals, which could be partially restored after receiving ART. The percentages of several subpopulations correlated with HIV-1 CA-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio, suggesting that changes in immune cell composition were associated with therapeutic efficacy. CONCLUSION: These data provide a complete profile of immune cell subpopulations or clusters that are associated with disease progression during chronic HIV-1 infection, which will improve understanding regarding the mechanism of incomplete immune recovery in INRs.

Severe intestinal barrier damage in HIV-infected immunological non-responders.

The intestinal epithelial barrier plays an important role during human immunodeficiency virus (HIV) disease progression. However, the extent to which the intestinal epithelial barrier is damaged in immunological non-responders (INRs) and immunological responders (IRs) is largely unknown. In this study, we investigated and compared the levels of intestinal gland damage and related molecules, including the tight junction protein claudin-1, apoptosis marker caspase-3, HIV DNA, CD4+ T cell count, and inflammation marker tumor necrosis factor-α (TNF-α) among the IRs (n = 10), INRs (n = 8), and healthy controls (HCs, n = 7). Intestinal damage was not completely restored in both INRs and IRs and was more serious in INRs than that in IRs. Moreover, intestinal damage was positively correlated with HIV DNA levels and negatively correlated with CD4+ T cell counts. These results provide insight into understanding the characteristics of intestinal epithelial barrier damage between IRs and INRs.

The Imbalance Between Intestinal Th17 and Treg Cells Is Associated with an Incomplete Immune Reconstitution During Long-Term Antiretroviral Therapy in Patients with HIV.

Studies assessing the gut mucosal immune balance in HIV-infected patients using intestinal samples are scarce. In this study, we used intestinal mucosal specimens from the ileocecal region of seven immunological nonresponders (INRs), nine immunological responders (IRs), and six HIV-negative controls. We investigated T helper 17 (Th17) and T regulatory (Treg) cell counts and their ratio, zonula occludens-1 (ZO-1), intestinal fatty acid-binding protein (I-FABP), tumor necrosis factor-α, CD4+ T cell counts, HIV DNA, and cell-associated HIV RNA. The results showed that INRs had lower Th17 and higher Treg cell counts than IR, resulting in a significant difference in the Th17/Treg ratio between IRs and INRs. In addition, INRs had lower ZO-1 and higher I-FABP levels than IRs. The Th17/Treg ratio was positively associated with ZO-1 and negatively associated with I-FABP levels. There was a positive correlation between Th17/Treg ratio and CD4+ T cell counts and a negative correlation between the Th17/Treg ratio and HIV DNA in the intestine. Our study suggests that the imbalance of Th17/Treg in the intestine is a characteristic of incomplete immune reconstitution to antiretroviral therapy and is associated with intestinal damage.

Serum globulin levels are associated with HIV reservoir size and immune restoration during long-term ART.

OBJECTIVES: The objectives of this study were to analyze the relationship between serum globulin levels and immune restoration and HIV reservoir size during long-term antiretroviral therapy (ART). METHODS: We enrolled 13 patients living with HIV who had been receiving ART for 5 years. We measured levels of serum globulin, cell-associated (CA) HIV DNA and RNA, and p24 antibody at 0, 1, 3, and 5 years of ART. CD38 and human leukocyte antigen - DR isotype (HLA-DR) were used as activation markers for T-cell activation. Serum concentrations of the inflammatory cytokines interferon gamma-inducible protein (IP)-10 and soluble CD163 (sCD163) were detected by enzyme-linked immunosorbent assay. We analyzed the relationship between serum globulin levels, HIV reservoir size, immune restoration, T-cell immune activation, and inflammatory levels during long-term ART. RESULTS: Our data showed that serum globulin levels in people living with HIV were higher than in healthy controls and significantly decreased during the first year of ART. Serum globulin levels during long-term ART were positively correlated with CA HIV DNA, CA HIV RNA, p24 antibody levels, and CD8+ T-cell counts and negatively correlated with CD4+ T-cell counts and CD4/CD8 ratios. Moreover, serum globulin levels were positively correlated with CD4+ and CD8+ T-cell activation and the concentrations of inflammatory biomarkers IP-10 and sCD163 during long-term ART. CONCLUSIONS: Our findings suggest that serum globulin levels may be associated with HIV reservoir size and immune restoration during long-term ART.

α4ß7high CD4+ T cells are prone to be infected by HIV-1 and associated with HIV-1 disease progression.

INTRODUCTION: To investigate the characteristics of ß7high CD4+ T cells during HIV-1 infection and the relationship between ß7high CD4+ T cells and HIV-1 disease progress. METHODS: This study enrolled 124 HIV-1-infected patients, including 80 treatment naïve patients (TNs), 41 patients who underwent antiretroviral therapy (ARTs), and three long-term no progression patients (LTNPs). Nineteen matched healthy subjects were included as controls (HCs). The characteristics and frequency of ß7high CD4+ T cells were analyzed using flow cytometry. An in vitro culture experiment was used to study HIV-1 infection of ß7high CD4+ T cells. Real-time polymerase chain reaction was performed to quantify HIV-1 DNA and CA-RNA levels. RESULTS: The frequency of ß7high CD4+ T in the peripheral blood was significantly decreased and negatively correlated with disease progression during chronic HIV-1 infection. A large proportion of ß7high CD4+ T cells showed Th17 phenotype. Furthermore, ß7high CD4+ T cells were preferentially infected by HIV-1 in vitro and in vivo. There were no significant differences of HIV-1 DNA, and CA-RNA levels between ß7high CD4+ T and ß7low CD4+ T subsets in HIV-1 infected individuals after antiviral treatment. CONCLUSION: The ß7high CD4+ T cells were negatively correlated with disease progression during chronic HIV-1 infection. ß7high CD4+ T cells are susceptible to infection with HIV-1 and HIV-1 latent cells.