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Ruiz-Riol M.,IrsiCaixa AIDS Research Institute HIVACAT | Mothe B.,IrsiCaixa AIDS Research Institute HIVACAT | Mothe B.,Autonomous University of Barcelona | Gandhi R.T.,Massachusetts General Hospital | And 5 more authors.
European Journal of Immunology | Year: 2013

The induction of cytotoxic T lymphocytes (CTLs) is believed to be an important defense mechanism against viral infections. The availability of simple, sensitive, specific and physiologically informative in vivo tests, applicable to humans, would greatly elucidate the nature of protective immune responses and facilitate immune monitoring in large vaccine trials. Here we studied the possibility of using defined HLA-A*02:01-restricted CTL epitopes from influenza matrix protein (GL9, GILGFVFTL) and HIV Gag p17 (SL9, SLYNTVATL) to elicit a cutaneous delayed-type hypersensitivity (DTH) reaction. Our results show that the GL9 but not the SL9 epitope was able to induce a DTH reaction. HIV infection status, HIV RNA level and CD4+ T-cell counts were not predictive of the extent of DTH reactions. However, a markedly reduced expression of skin homing markers CD103 and cutaneous lymphocyte associated Ag (CLA) on epitope-specific CTL populations was associated with a lack of SL9 DTH reactivity. These data demonstrate that DTH reactions can be elicited by optimally defined CTL epitopes per se and point towards specific homing markers that are required for such reactions. These data may offer new insights into the immune pathogenesis of HIV infection and provide the basis of novel immune monitoring approaches for large-scale HIV vaccine trials. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Mothe B.,IrsiCaixa AIDS Research Institute HIVACAT | Mothe B.,Autonomous University of Barcelona | Llano A.,IrsiCaixa AIDS Research Institute HIVACAT | Ibarrondo J.,IrsiCaixa AIDS Research Institute HIVACAT | And 35 more authors.
Journal of Translational Medicine | Year: 2011

Background: The efficacy of the CTL component of a future HIV-1 vaccine will depend on the induction of responses with the most potent antiviral activity and broad HLA class I restriction. However, current HIV vaccine designs are largely based on viral sequence alignments only, not incorporating experimental data on T cell function and specificity.Methods: Here, 950 untreated HIV-1 clade B or -C infected individuals were tested for responses to sets of 410 overlapping peptides (OLP) spanning the entire HIV-1 proteome. For each OLP, a "protective ratio" (PR) was calculated as the ratio of median viral loads (VL) between OLP non-responders and responders.Results: For both clades, there was a negative relationship between the PR and the entropy of the OLP sequence. There was also a significant additive effect of multiple responses to beneficial OLP. Responses to beneficial OLP were of significantly higher functional avidity than responses to non-beneficial OLP. They also had superior in-vitro antiviral activities and, importantly, were at least as predictive of individuals' viral loads than their HLA class I genotypes.Conclusions: The data thus identify immunogen sequence candidates for HIV and provide an approach for T cell immunogen design applicable to other viral infections. © 2011 Mothe et al; licensee BioMed Central Ltd. Source

Echeverria P.,Autonomous University of Barcelona | Bonjoch A.,Autonomous University of Barcelona | Puig J.,Autonomous University of Barcelona | Molto J.,Autonomous University of Barcelona | And 9 more authors.
PLoS ONE | Year: 2014

Background: Etravirine (ETR) was approved for patients with virological failure and antiretroviral resistance mutations. It has also shown antiviral efficacy in antiretroviral-naïve patients. However, data on the switching from protease inhibitors (PI) to ETR are lacking. Methods: HIV-1-infected patients with suppressed viral load (VL) during a PI-containing regimen (>12 months) and no previous virological failure were randomized to switch from the PI to ETR (400 mg/day, dissolved in water) (ETR group, n = 22) or to continue with the same regimen (control group, n = 21). Percentage of patients with VL≤50 copies/mL were assessed at week 48, as well as changes in CD4 T-cell counts and metabolic profile. Results: We included 43 patients [72.9% male, 46.3 (42.2; 50.6) years]. Two patients receiving ETR (grade-1 diarrhea and voluntary discontinuation) and another in the control group (simplification) discontinued therapy early. No patients presented virological failure (two consecutive VL>50 copies/mL); treatment was successful in 95.2% of the control group and 90.9% of the ETR group (intention-to-treat analysis, missing = failure) (p = 0.58). CD4+ T-cell counts did not significantly vary [+49 cells/μL in the ETR group (p = 0.25) and 24 cells/μL in the control group (p = 0.71)]. The ETR group showed significant reductions in cholesterol (p<0.001), triglycerides (p = <0.001), and glycemia (p = 0.03) and higher satisfaction (0-10 scale) (p = 0.04). Trough plasma concentrations of ETR were similar to observed in studies using ETR twice daily. Conclusion: Switch from a PI-based regimen to a once-daily combination based on ETR maintained undetectable VL during 48 weeks in virologically suppressed HIV-infected patients while lipid profile and patient satisfaction improved significantly. Trial Registration: ClinicalTrials.gov NCT01034917. © 2014 Echeverría et al. Source

Olvera A.,IrsiCaixa AIDS Research Institute HIVACAT | Perez-Alvarez S.,IrsiCaixa AIDS Research Institute HIVACAT | Perez-Alvarez S.,Autonomous University of Barcelona | Ibarrondo J.,University of California at Los Angeles | And 14 more authors.
AIDS | Year: 2015

Objective: The objective of this study is to identify human leukocyte antigen (HLA) class I and killer-cell immunoglobulin-like receptor (KIR) genotypes associated with different risks for HIV acquisition and HIV disease progression. Design: A cross-sectional study of a cohort of 468 high-risk individuals (246 HIV-positive and 222 HIV-negative) from outpatient clinics in Lima (Perú). Methods: The cohort was high-resolution HLA and KIR-typed and analysed for potential differences in single-allele frequencies and allele combinations between HIV-positive and HIV-negative individuals and for associations with HIV viral load and CD4+ cell counts in infected individuals. Results: HLA class I alleles associated with a lack of viral control had a significantly higher population frequency than relatively protective alleles (P = 0.0093), in line with a rare allele advantage. HLA-A∗02 : 01 and HLA-C∗04 : 01 were both associated with high viral loads (P = 0.0313 and 0.0001, respectively) and low CD4+ cell counts (P = 0.0008 and 0.0087, respectively). Importantly, the association between HLA-C∗04 : 01 and poor viral control was not due to its linkage disequilibrium with other HLA alleles. Rather, the coexpression of its putative KIR ligand KIR2DS4f was critically linked to elevated viral loads. Conclusion: These results highlight the impact of population allele frequency on viral control and identify a novel association between HLA-C∗04 : 01 in combination with KIR2DS4f and uncontrolled HIV infection. Our data further support the importance of the interplay of markers of the adaptive and innate immune system in viral control. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source

Mothe B.,IrsiCaixa AIDS Research Institute HIVACAT | Mothe B.,Autonomous University of Barcelona | Llano A.,IrsiCaixa AIDS Research Institute HIVACAT | Ibarrondo J.,IrsiCaixa AIDS Research Institute HIVACAT | And 25 more authors.
PLoS ONE | Year: 2012

Cytotoxic T lymphocyte (CTL) responses targeting specific HIV proteins, in particular Gag, have been associated with relative control of viral replication in vivo. However, Gag-specific CTL can also be detected in individuals who do not control the virus and it remains thus unclear how Gag-specific CTL may mediate the beneficial effects in some individuals but not in others. Here, we used a 10mer peptide set spanning HIV Gag-p24 to determine immunogen-specific T-cell responses and to assess functional properties including functional avidity and cross-reactivity in 25 HIV-1 controllers and 25 non-controllers without protective HLA class I alleles. Our data challenge the common belief that Gag-specific T cell responses dominate the virus-specific immunity exclusively in HIV-1 controllers as both groups mounted responses of comparable breadths and magnitudes against the p24 sequence. However, responses in controllers reacted to lower antigen concentrations and recognized more epitope variants than responses in non-controllers. These cross-sectional data, largely independent of particular HLA genetics and generated using direct ex-vivo samples thus identify T cell responses of high functional avidity and with broad variant reactivity as potential functional immune correlates of relative HIV control. © 2012 Mothe et al. Source

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