Browsing by Author "Salomon, Horacio"
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Item 7-oxo-DHEA enhances impaired M. tuberculosis-specific T cell responses during HIV-TB coinfection(2020-01-06) Vecchione, María Belén; Laufer, Natalia; Omar, Sued; Corti, Marcelo; Salomon, Horacio; Quiroga, Maria FlorenciaBackground Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), affecting approximately one third of the world’s population. Development of an adequate immune response will determine disease progression or progress to chronic infection. Risk of developing TB among human immunodeficiency virus (HIV)-coinfected patients (HIV-TB) is 20–30 times higher than those without HIV infection, and a synergistic interplay between these two pathogens accelerates the decline in immunological functions. TB treatment in HIV-TB coinfected persons is challenging and it has a prolonged duration, mainly due to the immune system failure to provide an adequate support for the therapy. Therefore, we aimed to study the role of the hormone 7-oxo-dehydroepiandrosterone (7-OD) as a modulator of anti-tuberculosis immune responses in the context of HIV-TB coinfection. Methods A cross-sectional study was conducted among HIV-TB patients and healthy donors (HD). We characterized the ex vivo phenotype of CD4 + T cells and also evaluated in vitro antigen-specific responses by Mtb stimulation of peripheral blood mononuclear cells (PBMCs) in the presence or absence of 7-OD. We assessed lymphoproliferative activity, cytokine production and master transcription factor profiles. Results Our results show that HIV-TB patients were not able to generate successful anti-tubercular responses in vitro compared to HD, as reduced IFN-γ/IL-10 and IFN-γ/IL-17A ratios were observed. Interestingly, treatment with 7-OD enhanced Th1 responses by increasing Mtb-induced proliferation and the production of IFN-γ and TNF-α over IL-10 levels. Additionally, in vitro Mtb stimulation augmented the frequency of cells with a regulatory phenotype, while 7-OD reduced the proportion of these subsets and induced an increase in CD4 + T-bet+ (Th1) subpopulation, which is associated with clinical data linked to an improved disease outcome. Conclusions We conclude that 7-OD modifies the cytokine balance and the phenotype of CD4 + T cells towards a more favorable profile for mycobacteria control. These results provide new data to delineate novel treatment approaches as co-adjuvant for the treatment of TB.Item Acute HIV Seroconversion Presenting with Active Tuberculosis and Associated with High Levels of T-Regulatory Cells(2011) Sued, Omar; Quiroga, Maria F.; Socias, Maria E.; Turk, Gabriela; Salomon, Horacio; Cahn, PedroA patient with well-defined acute HIV infection who developed concomitant pulmonary tuberculosis during the retroviral acute syndrome is reported here. In this patient high levels of T-regulatory cells (Tregs) and a low proliferation response to M. tuberculosis were initially detected, which normalized throughout follow-up. This case calls for the consideration of tuberculosis in patients in the early stages of HIV, and emphasizes the need for further study of the potential causal relationship between Treg cells and the risk of TB reactivation in HIV patients.Item Acute retroviral syndrome and high baseline viral load are predictors of rapid HIV progression among untreated Argentinean seroconverters(2011) Socias, Maria E.; Sued, Omar; Laufer, Natalia; Lázaro, Maria E.; Mingrone, Hugo; Remondegui, Claudio; Figueroa, Maria Ines; Cesar, Carina; Gun, Ana; Turk, Gabriela; Bouzas, Maria B.; Kavasery, Rosanna; Krolewiecki, Alejandro J.; Perez, Hector; Salomon, Horacio; Pryluka, DamianBackground Diagnosis of primary HIV infection (PHI) has important clinical and public health implications. HAART initiation at this stage remains controversial. Methods Our objective was to identify predictors of disease progression among Argentinean seroconverters during the first year of infection, within a multicentre registry of PHI-patients diagnosed between 1997 and 2008. Cox regression was used to analyze predictors of progression (LT-CD4 < 350 cells/mm3, B, C events or death) at 12 months among untreated patients. Results Among 134 subjects, 74% presented with acute retroviral syndrome (ARS). Seven opportunistic infections (one death), nine B events, and 10 non-AIDS defining serious events were observed. Among the 92 untreated patients, 24 (26%) progressed at 12 months versus three (7%) in the treated group (p = 0.01). The 12-month progression rate among untreated patients with ARS was 34% (95% CI 22.5-46.3) versus 13% (95% CI 1.1-24.7) in asymptomatic patients (p = 0.04). In univariate analysis, ARS, baseline LT-CD4 < 350 cells/mm3, and baseline and six-month viral load (VL) > 100,000 copies/mL were associated with progression. In multivariate analysis, only ARS and baseline VL > 100,000 copies/mL remained independently associated; HR: 8.44 (95% CI 0.97-73.42) and 9.44 (95% CI 1.38-64.68), respectively. Conclusions In Argentina, PHI is associated with significant morbidity. HAART should be considered in PHI patients with ARS and high baseline VL to prevent disease progression.Item Bioinformatic analysis of post-transmission viral readaptation in Argentine patients with acute HIV-1 infection(2020-07) Damilano, G; Sued, Omar; Satorres, S; Ruiz, Maria; Ghiglione, Y; Guzman, F; Turk, Gabriela ; Quiroga, F; Cahn, Pedro; Salomon, Horacio; Dilernia, DarioDuring the acute phase of HIV-1 infection, a strong readaptation occurs in the viral population. Our objective was to analyze the post-transmission mutations associated with escape to the cytotoxic immune response and its relationship with the progression of the infection. In this study, a total of 17 patients were enrolled during acute/early primary HIV infection and 8 subjects that were the HIV positive partner resulting in 8 transmission pairs. Genotyping of the genetic polymorphisms of HLA class I A and B was performed using PCR-SSOP. Viral RNA extraction was from plasma. 570 single Gag-gene amplifications were obtained by limiting-dilution RT-PCR. Epitope prediction was performed with NetMHC CBS prediction server for the 19 HLA-A and single bondB alleles. Cytotoxic response prediction was performed by using the IEDB Analysis Resource. From our results, we deduce that the transmitted CTL / gag escape frequency in the founder virus was at least double compared to the post-transmission events. Additionally, by means of an algorithm that combines these frequencies, we observed that the founder viruses better adapted to the HLA A / B alleles of the recipient could contribute to a greater progression of the infection. Our results suggest that there is a large adaptation of HIV-1 to the HLA A / B alleles prevalent in our population. However, despite this adaptive advantage, the virus needs to make “readjustments” through new escape and compensatory mutations. Interestingly, according to our results, this readaptation could have a role in the progression of the infection.Item Biomarkers of Progression after HIV Acute/Early Infection: Nothing Compares to CD4+ T-cell Count?(2018-01-13) Turk, Gabriela; Ghiglione, Yanina; Hormanstorfer, Macarena; Laufer, Natalia; Coloccini, Romina; Salido, Jimena; Trifone, César; Ruiz, Maria; Falivene, Juliana; Holgado, María Pía; Caruso, María Paula; Figueroa, María Inés; Salomon, Horacio ; Giavedoni, Luis D; De los Ángeles Pando, María; Gherardi, María Magdalena; Rabinovich, Roberto Daniel; Pury, Pedro A; Sued, OmarProgression of HIV infection is variable among individuals, and definition disease progression biomarkers is still needed. Here, we aimed to categorize the predictive potential of several variables using feature selection methods and decision trees. A total of seventy-five treatment-naïve subjects were enrolled during acute/early HIV infection. CD4+ T-cell counts (CD4TC) and viral load (VL) levels were determined at enrollment and for one year. Immune activation, HIV-specific immune response, Human Leukocyte Antigen (HLA) and C-C chemokine receptor type 5 (CCR5) genotypes, and plasma levels of 39 cytokines were determined. Data were analyzed by machine learning and non-parametric methods. Variable hierarchization was performed by Weka correlation-based feature selection and J48 decision tree. Plasma interleukin (IL)-10, interferon gamma-induced protein (IP)-10, soluble IL-2 receptor alpha (sIL-2Rα) and tumor necrosis factor alpha (TNF-α) levels correlated directly with baseline VL, whereas IL-2, TNF-α, fibroblast growth factor (FGF)-2 and macrophage inflammatory protein (MIP)-1β correlated directly with CD4+ T-cell activation (p < 0.05). However, none of these cytokines had good predictive values to distinguish “progressors” from “non-progressors”. Similarly, immune activation, HIV-specific immune responses and HLA/CCR5 genotypes had low discrimination power. Baseline CD4TC was the most potent discerning variable with a cut-off of 438 cells/μL (accuracy = 0.93, κ-Cohen = 0.85). Limited discerning power of the other factors might be related to frequency, variability and/or sampling time. Future studies based on decision trees to identify biomarkers of post-treatment control are warrantied.Item Computational comparison of availability in CTL/gag epitopes among patients with acute and chronic HIV-1 infection(2016) Damilano, Gabriel Dario; Sued, Omar; Ruiz, Maria; Ghiglione, Yanina; Canitano, Flavia; Pando, Maria; Turk, Gabriela; Cahn, Pedro; Salomon, Horacio; Dilernia, DarioBackground Recent studies indicate that there is selection bias for transmission of viral polymorphisms associated with higher viral fitness. Furthermore, after transmission and before a specific immune response is mounted in the recipient, the virus undergoes a number of reversions which allow an increase in their replicative capacity. These aspects, and others, affect the viral population characteristic of early acute infection. Methods 160 single gag-gene amplifications were obtained by limiting-dilution RT-PCR from plasma samples of 8 ARV-naïve patients with early acute infection (<30 days, 22 days average) and 8 ARV-naive patients with approximately a year of infection (10 amplicons per patient). Sanger sequencing and NGS SMRT technology (Pacific Biosciences) were implemented to sequence the amplicons. Phylogenetic analysis was performed by using MEGA 6.06. HLA-I (A and B) typing was performed by SSOP-PCR method. The chromatograms were analyzed with Sequencher 4.10. Epitopes and immune-proteosomal cleavages prediction was performed with CBS prediction server for the 30 HLA-A and -B alleles most prevalent in our population with peptide lengths from 8 to 14 mer. Cytotoxic response prediction was performed by using IEDB Analysis Resource. Results After implementing epitope prediction analysis, we identified a total number of 325 possible viral epitopes present in two or more acute or chronic patients. 60.3% (n = 196) of them were present only in acute infection (prevalent acute epitopes) while 39.7% (n = 129) were present only in chronic infection (prevalent chronic epitopes). Within p24, the difference was equally dramatic with 59.4% (79/133) being acute epitopes (p < 0.05). This is consistent with progressive viral adaptation to immune response in time and further supported by the fact that cytotoxic responses prediction showed that acute epitopes are more likely to generate immune response than chronic epitopes. Interestingly, only 27.5% of acute epitopes match the population-level consensus sequence of the virus. Conclusions Our results indicate that certain non-consensus viral residues might be transmitted more frequently than consensus-residues when located in immunological relevant positions (epitopes). This observation might be relevant to the rationale behind development of an effective vaccine to reduce viral reservoir and induce functional cure of HIV infection based in prevalent acute epitopes. Introduction Following transmission, Cytotoxic CD8+T lymphocytes (CTLs) mount a powerful response to transmitted HIV in the acute phase of infection [1]. However, the vast majority of cases is an inefficient response and directed to a limited number of epitopes [2]. This response is manifested producing a viral set point generally after first month of infection [3], [4], [5] with great specificity on the gag protein, which is strongly associated with control of viral replication [6], [7], [8], [9]. At this point, just after the peak of viremia, the first viral populations with HLA/CTL escape mutations are generated [2], which will increase over time and will have an impact on viral diversity during the chronic phase [10], [11], [12]. Therefore, it is interesting to investigate if these HLA-dependent reversions that occur during the acute phase are associated with a greater availability of epitopes in this stage. Reversions are another important aspect to be considered among viral factors shaping the viral diversity during the acute stage of infection [13], [14]. While their impact on viral fitness on transmitted/founder virus has not yet been elucidated, it is believes reversal mutations make the virus more fit [13], [15], [16].These post-transmission reversions may range from those associated with HLA alleles present on the donor [17], to the CD8 T-cell TCR receptor [13], [18], [19], to the proteasome [20], [21], or reversions that arise at random and increase the viral fitness that end up being established in the major viral population [22], [24]. Also, these reversions could occur prior to transmission, in a process of viral compartmentalization in mucosal associated tissues [25], [26], [27]. In this research, our objective was to determine, in patients under study, whether the viral sequences approach phylogenetically in acute patients compared with chronic patients. In turn, we evaluated whether possible reversions in acute viral sequences could significantly influence to decrease viral phylogenetic distance in these patients. Also, using computational prediction analysis, we evaluated the relationship of phylogenetically relevant amino acid positions (possibly reversions), with epitopes associated with cytotoxic immune response mediated by HLA I. Finally, we evaluated the distribution and characteristics of CTL epitopes, in conserved viral segments. We did an availability and frequency analysis of possible CTL epitopes found in the early acute phase compared to those found in the chronic phase.Item Correction: HLA-Driven Convergence of HIV-1 Viral Subtypes B and F Toward the Adaptation to Immune Responses in Human Populations(2008-11-04) Dilernia, Dario; Jones, Leandro; Rodriguez, Sabrina; Turk, Gabriela; Rubio, Andrea E; Pampuro, Sandra; Gomez-Carrillo, Manuel; Bautista, Christian T; Deluchi, Gabriel; Benetucci, Jorge; Lasala, María Beatriz; Lourtau, Leonardo; Losso, Marcelo Horacio; Perez, Héctor; Cahn, Pedro; Salomon, HoracioThe eighth author's name was displayed incorrectly. It should be: Christian T. Bautista.Item Cytomegalovirus UL97 mutations associated with ganciclovir resistance in immunocompromised patients from Argentina(2004) Sánchez Puch, Santiago; Ochoa, Carlos; Carballal, Guillermo; Zala, Carlos; Cahn, Pedro; Brunet, Ricardo; Salomon, Horacio; Videla, CeciliaBackground: Prolonged therapy with ganciclovir (GCV) can result in the development of GCV-resistant strains due to mutations in the viral phosphotransferase (UL97 gene) and/or in the viral DNA polymerase (UL54 gene). Objectives: The purpose of this study was to detect by molecular methods the most prevalent UL97 mutants which confer ganciclovir-resistance in immunocompromised populations. Study design: Patients from two populations were selected: (a) renal transplant patients with active cytomegalovirus (CMV) infection and more than one cycle of GCV; (b) HIV-infected patients with retinitis due to CMV, who were under GCV induction, maintenance therapy or withdrawal. Patients were followed up by pp65 antigenemia and by viral isolation from blood or/and urine samples. Two fragments (133 and 255pb) of the UL97 gene were amplified by polymerase chain reaction (PCR) from CMV isolates. Results: Nine from 12 isolates obtained were sequenced, three from two renal transplant patients and six from five HIV-infected patients. A UL97 mutation, known to confer GCV resistance, was found in two isolates from a renal transplant patient. A methionine to valine mutation at codon 460 (M460V) was detected. These isolates exhibited another mutation at codon 605, whose amino acid changed from aspartic acid (D) to glutamic acid (E). These findings were observed after treatment with IV-GCV/ O-GCV/ IV-GCV for 151 days. The 605 mutation was also detected in leukocytes from the same patient previous to the beginning of the treatment with GCV. Conclusions: Although a known resistant mutation appeared in a renal transplant patient, it was not associated with CMV disease. We suggest that the D605E mutation could "partially or totally compensate" for the effect of GCV resistance conferred by the 460 mutation. Further studies should be performed to confirm this hypothesis.Item Distribution of Bulk and HIV-specific CD8 + T Cell Memory Phenotypes during Acute/Early HIV Infection Is Related to Reduced Antiviral Activity(2014) Ghiglione, Yanina; Falivene, Juliana; Ruiz, Maria; Laufer, Natalia; Socias, Maria E.; Cahn, Pedro; Sued, Omar; Salomon, Horacio; Gherardi, María Magdalena; Turk, GabrielaBackground: Memory CD8+ T-cells are important components of protective immunity. Understanding their development during primary HIV infection (PHI) may contribute to optimal vaccine design. Aim: To analyze the distribution of memory subsets during PHI and their correlation with functionality and clinical parameters. Methods: 19 samples from acutely infected subjects were obtained at baseline and 12 months post-infection (mpi). Phenotypic (CD45RO, CCR7, PD-1) and functional markers (cytokines) were used to identify bulk and HIV-specific CD8+ memory populations. CD8 virus inhibitory assay (VIA) was performed. Data was compared intra-group and correlated to clinical parameters, PD-1 analysis and CD8 antiviral activity, using non-parametric statistics. Results: Bulk and HIV-specific CD8+ profile was terminal effectors (TE)>naïve>effector memory (TEM)>central memory. Spearman's correlation showed that baseline CD8+ VIA inversely correlated with the concurrent proportion of HIV-specific CD8+ TEM cells (r=-0.593, p=0.009) and directly correlated with the proportion of HIV-specific CD8+ TE cells (r=0.718, p=0.0008). Identical correlations were observed between baseline CD8+ T cell phenotype and CD8+ VIA at 12 mpi. Also, percentage of PD-1high CD8+ T cells negatively correlated with bulk and HIV-specific CD8+ TEM cells (r=−0.501, p=0.034 and r=−0.668, p=0.004, respectively). Conversely, positive correlations were observed with the proportion of bulk and HIV-specific CD8+ TE cells (r=-0.510, p=0.0308 and r=−0.564, p=0.022, respectively). Conclusions: A higher proportion of fully differentiated HIV-specific cells are related to the magnitude of CD8+ antiviral activity (rapidly able to exert effector functions) and to a higher PD-1 expression (related to T cell differentiation stage and activation status). This is the first report were a relation between CD8+ T cell memory differentiation hierarchy and antiviral function is reported during acute infection, providing information potentially useful for vaccine design.Item Dynamics of Adrenal Steroids Are Related to Variations in Th1 and Treg Populations during Mycobacterium tuberculosis Infection in HIV Positive Persons(2012) Quiroga, Maria F.; Angerami, Matias; Santucci, Natalia; Ameri, Daniel; Francos, Juan L.; Wallach, Julio; Sued, Omar; Cahn, Pedro; Salomon, Horacio; Bottasso, OsvaldoTuberculosis (TB) remains the most frequent cause of illness and death from an infectious agent, and its interaction with HIV has devastating effects. We determined plasma levels of dehydroepiandrosterone (DHEA), its circulating form DHEA-suphate (DHEA-s) and cortisol in different stages of M. tuberculosis infection, and explored their role on the Th1 and Treg populations during different scenarios of HIV-TB coinfection, including the immune reconstitution inflammatory syndrome (IRIS), a condition related to antiretroviral treatment. DHEA levels were diminished in HIV-TB and HIV-TB IRIS patients compared to healthy donors (HD), HIV+ individuals and HIV+ individuals with latent TB (HIV-LTB), whereas dehydroepiandrosterone sulfate (DHEA-s) levels were markedly diminished in HIV-TB IRIS individuals. HIV-TB and IRIS patients presented a cortisol/DHEA ratio significantly higher than HIV+, HIV-LTB and HD individuals. A positive correlation was observed between DHEA-s and CD4 count among HIV-TB individuals. Conversely, cortisol plasma level inversely correlated with CD4 count within HIV-TB individuals. M. tuberculosis-specific Th1 lymphocyte count was increased after culturing PBMC from HIV-TB individuals in presence of DHEA. We observed an inverse correlation between DHEA-s plasma level and Treg frequency in co-infected individuals, and CD4+FoxP3+ Treg frequency was increased in HIV-TB and IRIS patients compared to other groups. Strikingly, we observed a prominent CD4+CD25-FoxP3+ population across HIV-TB and HIV-TB IRIS patients, which frequency correlated with DHEA plasma level. Finally, DHEA treatment negatively regulated FoxP3 expression without altering Treg frequency in co-infected patients. These data suggest an enhancing role for DHEA in the immune response against M. tuberculosis during HIV-TB coinfection and IRIS.Item Early Gag Immunodominance of the HIV-Specific T-Cell Response during Acute/Early Infection Is Associated with Higher CD8(+) T-Cell Antiviral Activity and Correlates with Preservation of the CD4(+) T-Cell Compartment(2013) Turk, Gabriela; Ghiglione, Yanina; Falivene, Juliana; Socias, Maria E.; Laufer, Natalia; Coloccini, Romina.; Rodriguez, Ana María; Ruiz, Maria; Pando, María; Giavedoni, Luis; Cahn, Pedro; Sued, Omar; Salomon, Horacio; Gherardi, MaríaThe important role of the CD8+ T-cell response on HIV control is well established. Moreover, the acute phase of infection represents a proper scenario to delineate the antiviral cellular functions that best correlate with control. Here, multiple functional aspects (specificity, ex vivo viral inhibitory activity [VIA] and polyfunctionality) of the HIV-specific CD8+ T-cell subset arising early after infection, and their association with disease progression markers, were examined. Blood samples from 44 subjects recruited within 6 months from infection (primary HIV infection [PHI] group), 16 chronically infected subjects, 11 elite controllers (EC), and 10 healthy donors were obtained. Results indicated that, although Nef dominated the anti-HIV response during acute/early infection, a higher proportion of early anti-Gag T cells correlated with delayed progression. Polyfunctional HIV-specific CD8+ T cells were detected at early time points but did not associate with virus control. Conversely, higher CD4+ T-cell set points were observed in PHI subjects with higher HIV-specific CD8+ T-cell VIA at baseline. Importantly, VIA levels correlated with the magnitude of the anti-Gag cellular response. The advantage of Gag-specific cells may result from their enhanced ability to mediate lysis of infected cells (evidenced by a higher capacity to degranulate and to mediate VIA) and to simultaneously produce IFN-γ. Finally, Gag immunodominance was associated with elevated plasma levels of interleukin 2 (IL-2) and macrophage inflammatory protein 1β (MIP-1β). All together, this study underscores the importance of CD8+ T-cell specificity in the improved control of disease progression, which was related to the capacity of Gag-specific cells to mediate both lytic and nonlytic antiviral mechanisms at early time points postinfection.Item Early skewed differentiation and PD-1 expression in CD4+ cells relate to immune dysfunction and viral persistence in individuals living with HIV 1 year post-cART initiationSalido, Jorge; Czernikier, Ana; Trifone, Carolina; Figueroa, María Isabel; Salomon, Horacio; Cahn, Pedro; Sued, Omar; Laufer, Natalia; Ghiglione, Yanina; Turk, GabrielaAchieving HIV functional cure is a priority. Strategies such as adoptive cell transfer have been assayed, without success yet mainly due to immune dysfunctions observed among individuals. Samples from 25 HIV+ subjects were collected at diagnosis (baseline sample, BSL) and one year post-cART initiation (post- cART ). At BSL, bulk and HIV-specific CD4 phenotype (CD45RO , CCR 7, CD95 and PD1 expression) was assessed by flow cytometry after a short stimulation with HIV peptides. Also, proportion of CD4+/HLA-DR+/ CD38+ cells was measured. At post-cART , HIV-specific CD8TC s were obtained after 2-week expansion with peptides. Phenotype and antiviral activity (VIA and VITA L assays) were evaluated post-expansion. Plasma CXCL10 (IP-10) was assessed by ELISA. Cell-associated HIV DNA (total and integrated) and unspliced (US) and multiply-spliced (MS) RNA were quantified by real-time PCR. Non-parametric statistics were applied. Early CD4TC exhaustion, elevated activation and inadequate differentiation seem to be associated with viral persistence, inflammation, as well as with the phenotype and antiviral capacity of HIV-specific CD8TC s that persist one year after cART is initiated. These parameters could serve as predictors of CD8TC function on treated subjects.Item Early Skewed Distribution of Total and HIV-Specific CD8 T-Cell Memory Phenotypes during Primary HIV Infection Is Related to Reduced Antiviral Activity and Faster Disease Progression(2014-8) Ghiglione, Yanina; Falivene, Juliana; Ruiz, Maria; Laufer, Natalia; Socias, Maria E.; Cahn, Pedro; Giavedoni, Luis; Sued, Omar; Gherardi, María Magdalena; Salomon, Horacio; Turk, GabrielaThe important role of the CD8+ T-cells on HIV control is well established. However, correlates of immune protection remain elusive. Although the importance of CD8+ T-cell specificity and functionality in virus control has been underscored, further unraveling the link between CD8+ T-cell differentiation and viral control is needed. Here, an immunophenotypic analysis (in terms of memory markers and Programmed cell death 1 (PD-1) expression) of the CD8+ T-cell subset found in primary HIV infection (PHI) was performed. The aim was to seek for associations with functional properties of the CD8+ T-cell subsets, viral control and subsequent disease progression. Also, results were compared with samples from Chronics and Elite Controllers. It was found that normal maturation of total and HIV-specific CD8+ T-cells into memory subsets is skewed in PHI, but not at the dramatic level observed in Chronics. Within the HIV-specific compartment, this alteration was evidenced by an accumulation of effector memory CD8+ T (TEM) cells over fully differentiated terminal effector CD8+ T (TTE) cells. Furthermore, higher proportions of total and HIV-specific CD8+ TEM cells and higher HIV-specific TEM/(TEM+TTE) ratio correlated with markers of faster progression. Analysis of PD-1 expression on total and HIV-specific CD8+ T-cells from PHI subjects revealed not only an association with disease progression but also with skewed memory CD8+ T-cell differentiation. Most notably, significant direct correlations were obtained between the functional capacity of CD8+ T-cells to inhibit viral replication in vitro with higher proportions of fully-differentiated HIV-specific CD8+ TTE cells, both at baseline and at 12 months post-infection. Thus, a relationship between preservation of CD8+ T-cell differentiation pathway and cell functionality was established. This report presents evidence concerning the link among CD8+ T-cell function, phenotype and virus control, hence supporting the instauration of early interventions to prevent irreversible immune damage.Item Env-Specific IgA from Viremic HIV-Infected Subjects Compromises Antibody-Dependent Cellular Cytotoxicity(2016) Ruiz, Maria; Ghiglione, Yanina; Falivene, Juliana; Laufer, Natalia; Holgado, Maria Pia; Socias, Maria E.; Cahn, Pedro; Sued, Omar; Giavedoni, Luis; Salomon, Horacio; Gherardi, María Magdalena; Rodriguez, Ana María; Turk, GabrielaElucidating the factors that modulate HIV-specific antibody-dependent cellular cytotoxicity (ADCC) will help in understanding its role in HIV immunity. The aim of this study was to determine whether IgA could modify the magnitude of ADCC in HIV infection, abrogating its protective role. Plasma samples from 20 HIV-positive (HIV(+)) subjects enrolled during primary HIV infection (PHI), 10 chronically infected subjects (chronic), and 7 elite controllers (EC) were used. ADCC was determined by using a fluorometric ADCC assay, before and after removal of plasma IgA. Data were analyzed by using nonparametric statistics. ADCC was documented in 80% of PHI enrollment samples and in 100% of PHI 12-month, chronic, and EC samples; it peaked after acute infection, reached a plateau in chronic infection, and decreased after initiation of antiretroviral treatment (ART). Significant associations between ADCC and disease progression were found only after removal of plasma IgA from 12-month PHI samples: the magnitude of ADCC not only increased after IgA removal but also correlated with CD4(+) T-cell preservation. This work provides evidence that gp120-specific IgA was capable of modifying ADCC responses during natural HIV infection for the first time and adds to similar evidence provided in other settings. Furthermore, it underscores the complexity of the ADCC phenomenon and will help in an understanding of its underlying mechanisms. Importance: Although the induction of ADCC-mediating antibodies in HIV-infected subjects has been extensively documented, the association of these antibodies with protection from disease progression is poorly understood. Here, we demonstrate that plasma IgA is a factor capable of modifying the magnitude of IgG-mediated ADCC in HIV infection, mitigating its beneficial effect. These results help in understanding why previous studies failed to demonstrate correlations between ADCC and disease progression, and they also contribute to the notion that an HIV vaccine should stimulate the production of ADCC-mediating IgG antibodies but not IgA.Item Evaluation of Different Parameters of Humoral and Cellular Immune Responses in HIV Serodiscordant Heterosexual Couples: Humoral Response Potentially Implicated in Modulating Transmission Rates(2017-11-03) Ruiz, Maria; Salido, Jimena; Abusamra, Lorena; Ghiglione, Yanina; Cevallos, Cintia; Damilano, Gabriel; Rodriguez, Ana María; Trifone, César; Laufer, Natalia; Giavedoni, Luis D; Sued, Omar; Salomon, Horacio ; Gherardi, María Magdalena; Turk, GabrielaAs the HIV/AIDS pandemic still progresses, understanding the mechanisms governing viral transmission as well as protection from HIV acquisition is fundamental. In this context, cohorts of HIV serodiscordant heterosexual couples (SDC) represent a unique tool. The present study was aimed to evaluate specific parameters of innate, cellular and humoral immune responses in SDC. Specifically, plasma levels of cytokines and chemokines, HIV-specific T-cell responses, gp120-specific IgG and IgA antibodies, and HIV-specific antibody-dependent cellular cytotoxicity (ADCC) activity were assessed in nine HIV-exposed seronegative individuals (ESN) and their corresponding HIV seropositive partners (HIV+-P), in eighteen chronically infected HIV subjects (C), nine chronically infected subjects known to be HIV transmitters (CT) and ten healthy HIV− donors (HD). Very low magnitude HIV-specific cellular responses were found in two out of six ESN. Interestingly, HIV+-P had the highest ADCC magnitude, the lowest IgA levels and the highest IgG/IgA ratio, all compared to CT. Positive correlations between CD4+ T-cell counts and both IgG/IgA ratios and %ADCC killing uniquely distinguished HIV+-P. Additionally, evidence of IgA interference with ADCC responses from HIV+-P and CT is provided. These data suggest for the first time a potential role of ADCC and/or gp120-specific IgG/IgA balance in modulating heterosexual transmission. In sum, this study provides key information to understand the host factors that influence viral transmission, which should be considered in both the development of prophylactic vaccines and novel immunotherapies for HIV-1 infection.Item Expansion of CD25-Negative Forkhead Box P3-Positive T Cells during HIV and Mycobacterium tuberculosis Infection(2017-05-09) Angerami, Matías T; Suarez, Guadalupe V; Vecchione, María B; Laufer, Natalia; Ameri, Diego; Ben, Graciela; Perez, Hector; Sued, Omar; Salomon, Horacio ; Quiroga, María FTuberculosis (TB) and HIV alter the immune system, and coinfected (HIV-TB) individuals usually present deregulations of T-lymphocytic immune response. We previously observed an increased frequency of “unconventional” CD4+CD25−FoxP3+ Treg (uTreg) population during HIV-TB disease. Therefore, we aimed to explore the phenotype and function of uTreg and conventional CD4+CD25+FoxP3+ Treg subsets (cTreg) in this context. We evaluated the expression of CD39, programmed cell death protein 1 (PD1), glucocorticoid-induced tumor necrosis factor receptor (GITR), and the effector/memory distribution by flow cytometry in cTreg and uTreg. Also, IL-10, TGF-β, IFN-γ production, and the suppressor capacity of uTregs were analyzed in cocultures with effector lymphocytes and compared with the effect of regulatory T cells (Tregs). We found diminished expression of CD39 and higher levels of PD1 on uTreg compared to cTreg in both HIV-TB and healthy donors (HD). In addition, uTreg and cTreg showed differences in maturation status in both HIV-TB and HD groups, due to the expansion of effector memory uTregs. Interestingly, both HIV-TB and HD showed a pronounced production of IFN-γ in uTreg population, though no significant differences were observed for IL-10 and TGF-β production between uTreg and cTreg. Moreover, IFN-γ+ cells were restricted to the CD39− uTreg population. Finally, when the suppressor capacity was evaluated, both uTreg and cTreg inhibited polyclonal T cell-proliferation and IFN-γ production in a similar extent. These findings suggest that uTregs, which are expanded during HIV-TB coinfection, exert regulatory functions in a similar way to cTregs despite an altered surface expression of Treg characteristic markers and differences in cytokine production.Item Fostemsavir: a new CD4 attachment inhibitor(2018-10-23) Salido, Jimena; Ruiz, Maria; Trifone, César; Figueroa, María Inés; Caruso, María Paula; Gherardi, María Magdalena; Sued, Omar; Salomon, Horacio; Laufer, Natalia; Ghiglione, Yanina; Turk, GabrielaSince anti-HIV treatment cannot cure the infection, many strategies have been proposed to eradicate the viral reservoir, which still remains as a major challenge. The success of some of these strategies will rely on the ability of HIV-specific CD8+ T-cells (CD8TC) to clear reactivated infected cells. Here, we aimed to investigate the phenotype and function of in vitro expanded CD8TC obtained from HIV+ subjects on combination antiretroviral therapy (cART), either initiated earlier (median = 3 months postinfection, ET: Early treatment) or later (median = 20 months postinfection, DT: Delayed treatment) after infection. Peripheral blood mononuclear cells from 12 DT and 13 ET subjects were obtained and stimulated with Nef and Gag peptide pools plus IL-2 for 14 days. ELISPOT was performed pre- and post-expansion. CD8TC memory/effector phenotype, PD-1 expression, polyfunctionality (CD107a/b, IFN-γ, IL-2, CCL4 (MIP-1β), and/or TNF-α production) and antiviral activity were evaluated post-expansion. Magnitude of ELISPOT responses increased after expansion by 103 times, in both groups. Expanded cells were highly polyfunctional, regardless of time of cART initiation. The memory/effector phenotype distribution was sharply skewed toward an effector phenotype after expansion in both groups although ET subjects showed significantly higher proportions of stem-cell and central memory CD8TCs. PD-1 expression was clustered in HIV-specific effector memory CD8TCs, subset that also showed the highest proportion of cytokine–producing cells. Moreover, PD-1 expression directly correlated with CD8TC functionality. Expanded CD8TCs from DT and ET subjects were highly capable of mediating antiviral activity, measured by two different assays. Antiviral function directly correlated with the proportion of fully differentiated effector cells (viral inhibition assay) as well as with CD8TC polyfunctionality and PD-1 expression (VITAL assay). In sum, we show that, despite being dampened in subjects on cART, the HIV-specific CD8TC response could be selectively stimulated and expanded in vitro, presenting a high proportion of cells able to carry-out multiple effector functions. Timing of cART initiation had an impact on the memory/effector differentiation phenotype, most likely reflecting how different periods of antigen persistence affected immune function. Overall, these results have important implications for the design and evaluation of strategies aimed at modulating CD8TCs to achieve the HIV functional cure.Item Hepatitis B virus, hepatitis C virus and HIV coinfection among people living with HIV/AIDS in Buenos Aires, Argentina(2010) Laufer, Natalia; Quarleri, Jorge; Bouzas, Maria B.; Juncos, Gerardo; Cabrini, Mercedes; Moretti, Franco; Bolcic, Federico; Fernández-Giuliano, Silvina; Mammana, Lilia; Salomon, Horacio; Cahn, PedroThe HIV epidemic in Argentina has changed since the first case was reported in 1982. Since the beginning of the 1990s, a decrease in the number parenterally acquired infections has been observed, with a marked increase in transmission through unprotected sexual contact (heterosexual and homosexual), and in the number of women living with HIV/AIDS [1]. Few prevalence studies have addressed the hepatitis B and C virus coinfection in Argentina. We performed this study in a large single clinic in Buenos Aires, taking care of more than 3,000 HIV patients. During a seven-month period (9/2004 to 3/2005), all HIV-positive patients ≥ 18 years old, who were followed up at our unit and who had their scheduled controls for HIV viral load (VL) at the Argentinean National Reference Centre for AIDS (CNRS), were invited to participate in the study. The study was approved by the Fernández Hospital Ethics Committee. Patients gave their informed consent to be included in the study. Six hundred subjects were asked to enter the study, and 593 accepted. Studied population: 65.6% males, 64% young adults between 20 and 40 years old. The main route of HIV infection was through sexual contact (70%). Of the 593 samples, 52% (n=308) showed positive results for serological markers (HBcAb/HBsAg/anti-HCV) for hepatitis B or C coinfection. Coinfection rates and subjects characteristics are described in Table 1.Item Hepatitis C Virus (HCV) Clearance After Treatment With Direct-Acting Antivirals in Human Immunodeficiency Virus (HIV)-HCV Coinfection Modulates Systemic Immune Activation and HIV Transcription on Antiretroviral Therapy(2020-04-02) Ghiglione, Yanina; Polo, María Laura; Urioste, Alejandra; Rhodes, Ajantha; Czernikier, Alejandro; Trifone, César; Florencia Quiroga, María; Sisto, Alicia; Patterson, Patricia; Salomon, Horacio ; Rolón, María José; Bakkour, Sonia; Lewin, Sharon R; Turk, Gabriela; Laufer, Nataliahttps://doi.org/10.1093/ofid/ofaa115Item Higher Rate of Toxicity With No Increased Efficacy When Hydroxyurea Is Added to a Regimen of Stavudine Plus Didanosine and Nevirapine in Primary HIV Infection(2002-04-01) Zala, Carlos; Salomon, Horacio; Ochoa, Claudia; Kijak, Gustavo; Federico, Andrea; Perez, Héctor; Julio SG, Montaner; Cahn, PedroSummary: Twenty-four subjects presenting at a single treatment center with primary HIV infection were enrolled in a pilot study aimed to establish the possible role of hydroxyurea in this setting. Study participants were randomly assigned to receive or not to receive hydroxyurea in addition to stavudine (d4T) plus didanosine (ddI) and nevirapine (NVP). Seventy-five percent of patients without hydroxyurea had plasma HIV RNA below 50 copies/mL at 48 weeks by both intention-to-treat (ITT) and on-treatment (OT) analysis in comparison with 50% (ITT) and 67% (OT) of patients with hydroxyurea (p > .1). A median increase of >200 cells/mm3 was observed from baseline to week 48 whether or not hydroxyurea was included in the regimen. Overall, in 12 patients treated with hydroxyurea, 33 adverse events were reported versus 19 reported for 12 patients who did not receive hydroxyurea (p < .05). Our results suggest that that adding hydroxyurea to a regimen of d4T plus ddI and NVP increases toxicity without improving the antiviral effect.