Proviral Quasispecies Diversity Is Not Associated With Virologic Breakthrough or CD4+ T Cell Loss in HIV-1 Elite Controllers

Elite controllers (EC) are able to control HIV-1 replication to extremely low levels (<50 HIV-1 RNA copies/mL) in the absence of antiretroviral therapy. However, some EC experience CD4+ T cell loss and/or lose their ability to control HIV-1 over the course of infection. High levels of HIV-1 env proviral diversity, activated T cells and proinflammatory cytokines were pointed out as relevant biomarkers for detection of EC at risk of virologic/immunologic progression. The aim of this study was to assess the importance of proviral diversity as a prognostic marker of virologic and/or immunologic progression in EC. To this end, we analyzed plasma viremia, total HIV DNA levels, T cells dynamics, and activation/inflammatory biomarkers in EC with low (ECLD = 4) and high (ECHD = 6) HIV-1 env diversity. None of ECLD and ECHD subjects displayed evidence of immunologic progression (decrease in absolute and percentage of CD4+ T cells) and only one ECHD subject presented virologic progression (≥2 consecutive viral loads measurements above the detection limit) 2–5 years after determination of proviral env diversity. Despite differences in proviral genetic diversity, the ECLD and ECHD subgroups displayed comparable levels of total cell-associated HIV DNA, activated CD8+ T (CD38+HLA-DR+) cells and plasmatic inflammatory biomarkers (IP-10, IL-18, RANTES, PDGF-AA, and CTACK). These results indicate that the genetic diversity of the HIV-1 proviral reservoir is not a surrogate marker of residual viral replication, immune activation or inflammation, nor an accurate biomarker for the prediction of virologic breakthrough or CD4+ T cells loss in EC

Plasmatic Levels of IL-18, IP-10, and Activated CD8+ T Cells Are Potential Biomarkers to Identify HIV-1 Elite Controllers With a True Functional Cure Profile

Elite controllers (ECs) are rare individuals able to naturally control HIV-1 replication below the detection limit of viral load (VL) commercial assays. It is unclear, however, whether ECs might be considered a natural model of a functional cure because some studies have noted CD4+ T cell depletion and disease progression associated with abnormally high levels of immune activation and/or inflammation in this group. Here, we propose the use of immunological parameters to identify HIV-1 ECs that could represent the best model of a functional cure. We compared plasma levels of six inflammatory biomarkers (IP-10, IL-18, sCD163, sCD14, CRP, and IL-6) and percentages of activated CD8+ T cells (CD38+HLA-DR+) between 15 ECs [8 with persistent undetectable viremia (persistent elite controllers) and 7 with occasional viral blips (ebbing elite controllers)], 13 viremic controllers (VCs—plasma VL between 51 and 2,000 RNA copies/mL), and 18 HIV-1 infected patients in combined antiretroviral therapy, with suppressed viremia, and 18 HIV-uninfected controls (HIV-neg). The two groups of ECs presented inflammation and activation profiles similar to HIV-neg individuals, and there was no evidence of CD4+ T cell decline over time. VCs, by contrast, had higher levels of IL-18, IP-10, and CRP and a lower CD4/CD8 ratio than that of HIV-neg (P < 0.05). Plasma levels of IL-18 and IP-10 correlated positively with CD8+ T cell activation and negatively with both CD4/CD8 and CD4% in HIV-1 controllers. These results suggest that most ECs, defined using stringent criteria in relation to the cutoff level of viremia (≤50 copies/mL) and a minimum follow-up time of >5 years, show no evidence of persistent inflammation or immune activation. This study further suggests that plasmatic levels of IL-18/IP-10 combined with the frequency of CD8+CD38+HLA-DR+ T cells can be important biomarkers to identify models of a functional cure among HIV-1 ECs

HIV-1 elite controllers present a high frequency of activated regulatory T and Th17 cells.

HIV-1 infection is characterized by generalized deregulation of the immune system, resulting in increased chronic immune activation. However, some individuals called HIV controllers (HICs) present spontaneous control of viral replication and have a more preserved immune system. Among HICs, discordant results have been observed regarding immune activation and the frequency of different T cell subsets, including Treg and Th17 cells. We evaluated T cell immune activation, differentiation and regulatory profiles in two groups of HICs-elite controllers (ECs) and viremic controllers (VCs)-and compared them to those of cART-treated individuals (cART) and HIV-1-negative (HIV-neg) individuals. ECs demonstrated similar levels of activated CD4+ and CD8+ T cells in comparison to HIV-neg, while cART and VCs showed elevated T cell activation. CD4+ T cell subset analyses showed differences only for transitional memory T cell frequency between the EC and HIV-neg groups. However, VC individuals showed higher frequencies of terminally differentiated, naïve, and stem cell memory T cells and lower frequencies of transitional memory and central memory T cells compared to the HIV-neg group. Among CD8+ T cell subsets, ECs presented higher frequencies of stem cell memory T cells, while VCs presented higher frequencies of terminally differentiated T cells compared to the HIV-neg group. HICs showed lower frequencies of total Treg cells compared to the HIV-neg and cART groups. ECs also presented higher frequencies of activated and a lower frequency of resting Treg cells than the HIV-neg and cART groups. Furthermore, we observed a high frequency of Th17 cells in ECs and high Th17/Treg ratios in both HIC groups. Our data showed that ECs had low levels of activated T cells and a high frequency of activated Treg and Th17 cells, which could restrict chronic immune activation and be indicative of a preserved mucosal response in these individuals

HIV controllers with different viral load cut-off levels have distinct virologic and immunologic profiles

Submitted by sandra infurna ([email protected]) on 2016-04-05T13:12:25Z No. of bitstreams: 1 fernanda_cortes_etal_IOC_2015.pdf: 720405 bytes, checksum: e4ef65f6aa4098f1ff80207771af65c0 (MD5)Approved for entry into archive by sandra infurna ([email protected]) on 2016-04-05T13:31:20Z (GMT) No. of bitstreams: 1 fernanda_cortes_etal_IOC_2015.pdf: 720405 bytes, checksum: e4ef65f6aa4098f1ff80207771af65c0 (MD5)Made available in DSpace on 2016-04-05T13:31:20Z (GMT). No. of bitstreams: 1 fernanda_cortes_etal_IOC_2015.pdf: 720405 bytes, checksum: e4ef65f6aa4098f1ff80207771af65c0 (MD5) Previous issue date: 2015Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de AIDS e Imunologia Molecular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de AIDS e Imunologia Molecular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de AIDS e Imunologia Molecular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de AIDS e Imunologia Molecular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Infectologia Evandro Chagas - INI. Rio de Janeiro, RJ, Brasil.University of Miami. Miller School of Medicine. Department of Medicine. Miami, FL, USA.University of Miami. Miller School of Medicine. Department of Medicine. Miami, FL, USA.Fundação Oswaldo Cruz. Instituto Nacional de Infectologia Evandro Chagas - INI. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Nacional de Infectologia Evandro Chagas - INI. Rio de Janeiro, RJ, Brasil.University of Miami. Miller School of Medicine. Department of Medicine. Miami, FL, USA.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de AIDS e Imunologia Molecular. Rio de Janeiro, RJ, Brasil.Background—The mechanisms behind natural control of HIV replication are still unclear, and several studies pointed that elite controllers are a heterogeneous group. Methods—We performed analyses of virologic, genetic and immunologic parameters of HIV-1 controllers groups: 1) Elite Controllers (EC; VL <80 copies/mL); 2) Ebbing Elite Controllers (EEC; transient viremia/blips); and Viremic Controllers (VC; detectable viremia <5,000 copies/ mL). Untreated non-controllers (NC), patients under suppressive HAART and HIV-1 negative individuals were analyzed as controls. Results—Total and integrated HIV-1 DNA for EC were significantly lower than for NC and HAART groups. 2-LTR circles were detected in EEC (3/5) and VC (6/7) but not in EC. While EC and EEC maintain normal T cell counts over time, some VC displayed negative CD4+ T cells slopes. VC and EEC showed a higher percentage of activated CD8+ T cells and microbial translocation than HIV-1 negative controls. EC displayed a weaker Gag/Nef IFN-γ T cell response and a significantly lower proportion of anti-HIV IgG antibodies than EEC, VC and NC groups. Conclusion—Transient/persistent low level viremia in HIV controllers may have an impact on immunologic and virologic profiles. Classify HIV controllers patients taking into account their virologic profile may decrease the heterogeneity of HIV controllers cohorts, which may help to clarify the mechanisms associated to the elite control of HIV

data_sheet_1_Plasmatic Levels of IL-18, IP-10, and Activated CD8+ T Cells Are Potential Biomarkers to Identify HIV-1 Elite Controllers With a True Functional Cure Profile.docx

<p>Elite controllers (ECs) are rare individuals able to naturally control HIV-1 replication below the detection limit of viral load (VL) commercial assays. It is unclear, however, whether ECs might be considered a natural model of a functional cure because some studies have noted CD4⁺ T cell depletion and disease progression associated with abnormally high levels of immune activation and/or inflammation in this group. Here, we propose the use of immunological parameters to identify HIV-1 ECs that could represent the best model of a functional cure. We compared plasma levels of six inflammatory biomarkers (IP-10, IL-18, sCD163, sCD14, CRP, and IL-6) and percentages of activated CD8⁺ T cells (CD38⁺HLA-DR⁺) between 15 ECs [8 with persistent undetectable viremia (persistent elite controllers) and 7 with occasional viral blips (ebbing elite controllers)], 13 viremic controllers (VCs—plasma VL between 51 and 2,000 RNA copies/mL), and 18 HIV-1 infected patients in combined antiretroviral therapy, with suppressed viremia, and 18 HIV-uninfected controls (HIV-neg). The two groups of ECs presented inflammation and activation profiles similar to HIV-neg individuals, and there was no evidence of CD4⁺ T cell decline over time. VCs, by contrast, had higher levels of IL-18, IP-10, and CRP and a lower CD4/CD8 ratio than that of HIV-neg (P < 0.05). Plasma levels of IL-18 and IP-10 correlated positively with CD8⁺ T cell activation and negatively with both CD4/CD8 and CD4% in HIV-1 controllers. These results suggest that most ECs, defined using stringent criteria in relation to the cutoff level of viremia (≤50 copies/mL) and a minimum follow-up time of >5 years, show no evidence of persistent inflammation or immune activation. This study further suggests that plasmatic levels of IL-18/IP-10 combined with the frequency of CD8⁺CD38⁺HLA-DR⁺ T cells can be important biomarkers to identify models of a functional cure among HIV-1 ECs.</p