DSpace Repository :: Browsing by Author "Laufer, Natalia"

Browsing by Author "Laufer, Natalia"

Now showing 1 - 20 of 28

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 Florencia
Background 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.
A dynamic interplay of circulating extracellular vesicles and galectin-1 reprograms viral latency during HIV-1 infection
(2019) Rubione, Julieta; Duette, Gabriela; Perez, Paula; Pereyra Gerber, Pablo; Salido, Jorge; Cagnoni, Ana; Guzman, Laura; Adamczyk, Ariel; Sued, Omar; Ghiglione, Yanina; Laufer, Natalia; Mariño, Karina; Rabinovich, Gabriel; Ostrowski, Mario
HIV-positive individuals on antiretroviral therapy(art) have detectable cell-associated unspliced (ca-Us) HIV rNain cD4+ t-cells from blood which varies with time. additionally, werecently showed that circadian transcription factors, circadian Loco-motor output cycles Kaput (cLocK) and brain and Muscle arnt-likeprotein-1 (bMaL1), bind to the HIV Ltr and increase HIV transcrip-tion. We hypothesised that circadian rhythms exert transcriptionalcontrol on latent HIV.
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, Damian
Background 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.
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, Omar
Progression 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.
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, Gabriela
Background: 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.
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, María
The 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.
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 initiation
Salido, Jorge; Czernikier, Ana; Trifone, Carolina; Figueroa, María Isabel; Salomon, Horacio; Cahn, Pedro; Sued, Omar; Laufer, Natalia; Ghiglione, Yanina; Turk, Gabriela
Achieving 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.
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, Gabriela
The 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.
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, Gabriela
Elucidating 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.
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, Gabriela
As 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.
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 F
Tuberculosis (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.
Exposición ocupacional al virus de la hepatitis C
(2007) Ricart, Javier J.; Fink, Valeria; Cabrini, Mercedes; Figueroa, Maria Ines; Laufer, Natalia; Cahn, Pedro
La transmisión ocupacional de virus de hepatitis C (VHC) es un área de creciente preocupación dada la falta de profilaxis y la poca información de su prevalencia en el medio hospitalario. Sobre 128 exposiciones ocupacionales ocurridas en el Hospital Diego Paroissien entre1999 y 2003 hubieron 8 casos de exposición a VHC (6.3%) y un caso de seroconversión posterior a la exposición (0.8%). No existiendo en la actualidad terapia preventiva para VHC resulta de gran interés la posibilidad de tratamiento de la infección aguda. La mayor parte de los autores coincide en recomendar el tratamiento del episodio agudo de hepatitis por VHC basado en la evidencia actual, aunque aún no está bien definida la mejor estrategia diagnóstica y terapéutica. El acatamiento de las Normas de Precauciones Universales sigue siendo en la actualidad la más importante medida preventiva para evitar la infección ocupacional por VHC en el personal de salud y la de mejor equilibrio costo-beneficio.
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, Gabriela
Since 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.
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, Pedro
The 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.
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, Natalia
https://doi.org/10.1093/ofid/ofaa115
HIV-TB co-infection impairs CD8+ T-cell differentiation and function while dehydroepiandrosterone improves cytotoxic anti-tubercular immune responses
(2015-9) Suarez, Guadalupe V.; Angerami, Matias; Vecchione, María B.; Laufer, Natalia; Turk, Gabriela; Ruiz, Maria; Mesch, Viviana; Fabre, Bibiana; Maidana, Patricia; Ameri, Diego; Cahn, Pedro; Sued, Omar; Salomon, Horacio; Bottasso, Oscar A.; Quiroga, María F.
Tuberculosis (TB) is the leading cause of death among HIV-positive patients. The decreasing frequencies of terminal effector (TTE) CD8+T cells may increase reactivation risk in persons latently infected with Mycobacterium tuberculosis (Mtb). We have previously shown that dehydroepiandrosterone (DHEA) increases the protective antitubercular immune responses in HIV–TB patients. Here, we aimed to study Mtb-specific cytotoxicity, IFN-γ secretion, memory status of CD8+T cells, and their modulation by DHEA during HIV–TB coinfection. CD8+T cells from HIV–TB patients showed a more differentiated phenotype with diminished naïve and higher effector memory and TTE T-cell frequencies compared to healthy donors both in total and Mtb-specific CD8+T cells. Notably, CD8+T cells from HIV–TB patients displayed higher Terminal Effector (TTE) CD45RAdim proportions with lower CD45RA expression levels, suggesting a not fully differentiated phenotype. Also, PD-1 expression levels on CD8+T cells from HIV–TB patients increased although restricted to the CD27+ population. Interestingly, DHEA plasma levels positively correlated with TTE in CD8+T cells and in vitro DHEA treatment enhanced Mtb-specific cytotoxic responses and terminal differentiation in CD8+T cells from HIV–TB patients. Our data suggest that HIV–TB coinfection promotes a deficient CD8+ T-cell differentiation, whereas DHEA may contribute to improving antitubercular immunity by enhancing CD8+T-cell functions during HIV–TB coinfection.
Host Genetic Factors Associated with Symptomatic Primary HIV Infection and Disease Progression among Argentinean Seroconverters
(2014) Coloccini, Romina; Dilernia, Dario; Ghiglione, Yanina; Turk, Gabriela; Laufer, Natalia; Rubio, Andrea; Socias, Maria E.; Figueroa, Maria Ines; Sued, Omar; Cahn, Pedro; Salomon, Horacio; Mangano, Andrea; Pando, María Angeles
Background Variants in HIV-coreceptor C-C chemokine receptor type 5 (CCR5) and Human leukocyte antigen (HLA) genes are the most important host genetic factors associated with HIV infection and disease progression. Our aim was to analyze the association of these genetic factors in the presence of clinical symptoms during Primary HIV Infection (PHI) and disease progression within the first year. Methods Seventy subjects diagnosed during PHI were studied (55 symptomatic and 15 asymptomatic). Viral load (VL) and CD4 T-cell count were evaluated. HIV progression was defined by presence of B or C events and/or CD4 T-cell counts <350 cell/mm3. CCR5 haplotypes were characterized by polymerase chain reaction and SDM-PCR-RFLP. HLA-I characterization was performed by Sequencing. Results Symptoms during PHI were significantly associated with lower frequency of CCR5-CF1 (1.8% vs. 26.7%, p = 0.006). Rapid progression was significantly associated with higher frequency of CCR5-CF2 (16.7% vs. 0%, p = 0.024) and HLA-A*11 (16.7% vs. 1.2%, p = 0.003) and lower frequency of HLA-C*3 (2.8% vs. 17.5%, p = 0.035). Higher baseline VL was significantly associated with presence of HLA-A*11, HLA-A*24, and absence of HLA-A*31 and HLA-B*57. Higher 6-month VL was significantly associated with presence of CCR5-HHE, HLA-A*24, HLA-B*53, and absence of HLA-A*31 and CCR5-CF1. Lower baseline CD4 T-cell count was significantly associated with presence of HLA-A*24/*33, HLA-B*53, CCR5-CF2 and absence of HLA-A*01/*23 and CCR5-HHA. Lower 6-month CD4 T-cell count was associated with presence of HLA-A*24 and HLA-B*53, and absence of HLA-A*01 and HLA-B*07/*39. Moreover, lower 12-month CD4 T-cell count was significantly associated with presence of HLA-A*33, HLA-B*14, HLA-C*08, CCR5-CF2, and absence of HLA-B*07 and HLA-C*07. Conclusion Several host factors were significantly associated with disease progression in PHI subjects. Most results agree with previous studies performed in other groups. However, some genetic factor associations are being described for the first time, highlighting the importance of genetic studies at a local level.
ICOS, SLAM and PD-1 expression and regulation on T lymphocytes reflect the immune dysregulation in patients with HIV-related illness with pulmonary tuberculosis
(2012) Jurado, Jorge O.; Pasquinelli, Virginia; Alvarez, Ivan B.; Martínez, Griselda J.; Laufer, Natalia; Sued, Omar; Cahn, Pedro; Musella, Roberto M.; Abbate, Esteban; Salomon, Horacio; Quiroga, Maria F.
Background: Tuberculosis (TB) continues to be the most frequent cause of illness and death from an infectious agent globally, and its interaction with HIV is having devastating effects. To investigate how HIV alters the immune response to Mycobacterium tuberculosis (Mtb), we assessed basal and Mtb-induced proliferation, cytokine production, and expression of signalling lymphocytic activation molecule (SLAM), inducible costimulator (ICOS) and programmed death-1 (PD-1) on T lymphocytes from HIV-positive individuals coinfected with TB, HIV-positive subjects, TB patients and healthy donors (HD). Findings: HIV-TB patients showed increased ICOS, SLAM and PD-1 basal levels on T lymphocytes, whereas HIV-positive individuals displayed elevated levels of SLAM and PD-1, TB patients high levels of SLAM, and HD low levels of the three proteins. Mtb-stimulation enhanced ICOS expression in the four groups, but only TB and HD increased SLAM and PD-1 levels. Conclusions: These data show the immune deregulation that takes place during the immune response against TB in different study populations.
Immune variations throughout the course of tuberculosis treatment and its relationship with adrenal hormone changes in HIV-1 patients co-infected with Mycobacterium tuberculosis
(2022-03) Vecchione, María Belén; Angerami, Matias; Suarez, Guadalupe Verónica; Turk, Gabriela; Laufer, Natalia; Ben, Graciela; Ameri, Diego; Gonzalez, Diego; Parodi, Laura M.; Giavedoni, Luis D.; Maidana, Patricia; Fabre, Bibiana; Mesch, Viviana; Sued, Omar; Quiroga, Maria Florencia
HIV infection is a major risk factor predisposing for Mycobacterium tuberculosis infection and progression to active tuberculosis (TB). As host immune response defines the course of infection, we aimed to identify immuno-endocrine changes over six-months of anti-TB chemotherapy in HIV+ people. Plasma levels of cortisol, DHEA and DHEA-S, percentages of CD4+ regulatory T cell subsets and number of IFN-γ-secreting cells were determined. Several cytokines, chemokines and C-reactive protein levels were measured. Results were correlated with clinical parameters as predictors of infection resolution and compared to similar data from HIV+ individuals, HIV-infected persons with latent TB infection and healthy donors. Throughout the course of anti-TB/HIV treatment, DHEA and DHEA-S plasma levels raised while cortisol diminished, which correlated to predictive factors of infection resolution. Furthermore, the balance between cortisol and DHEA, together with clinical assessment, may be considered as an indicator of clinical outcome after anti-TB treatment in HIV+ individuals. Clinical improvement was associated with reduced frequency of unconventional Tregs, increment in IFN-γ-secreting cells, diminution of systemic inflammation and changes of circulating cytokines and chemokines. This study suggests that the combined anti-HIV/TB therapies result in partial restoration of both, immune function and adrenal hormone plasma levels.
Low Rate of Emergence of Nevirapine and Lamivudine Resistance after Post-Partum Interruption of a Triple-Drug Regimen
(2008-01-01) Pérez, Héctor; Vignoles, Moira; Laufer, Natalia; Gómez, Alejandro; Coll, Patricia; Lattner, Jorge; Rolón, María José; Salomon, Horacio ; Cahn, Pedro
Introduction Emergence of nevirapine (NVP) resistance may be a consequence of its use in monotherapy to prevent HIV mother-to-child transmission (MTCT). The aim of this study was to evaluate the emergence of strains resistant to NVP and lamivudine (3TC) after discontinuation of anti-retroviral therapy (ART) with 3TC/zidovudine (ZDV)/NVP. Methods Twenty pregnant women (ART-naive or pre-exposed only to ZDV), to whom 3TC/ZDV/NVP was prescribed as MTCT prophylaxis, were studied. They received ART for a median of 4 months with median viral load (VL) at labour <50 copies/ml. Samples were collected between 1 and 15 months (median: 3 months) after ART interruption. Sequence-selective real-time PCR (SPCR), which quantifies minority viral populations containing K103N, Y181C and M184V mutations, and standard genotypic sequencing were assayed. Results No mutations associated with resistance to 3TC or NVP were found by standard population sequencing. Analysis of K103N by SPCR showed that 35% of the patients contained ≤0.1% of viruses carrying either the AAC or AAT mutations. For Y181C mutation, 10% of the patients contained <0.5% of viruses with TGT codon change. For M184V mutation, one patient contained 6.2% of virus with GTG mutation and 13 patients (65%) contained <0.9% of mutated viruses. Four women were re-exposed to 3TC/ZDV/NVP and achieved HIV VL <50 copies/ml. No perinatal transmission occurred in any of the 22 births. Conclusions NVP associated with ZDV/3TC as a regimen to prevent MTCT may involve a low risk for the selection of antiretroviral-resistant strains and may not jeopardize the use of these same drugs for future treatment.

Browsing by Author "Laufer, Natalia"

Results Per Page

Sort Options