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.

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 1ß (MIP-1ß). 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.

[Prevalence of HIV infection and Treponema pallidum in Argentine female sex workers]. / Prevalencia de la infección por el VIH y de Treponema pallidum en mujeres trabajadoras sexuales de Argentina.

OBJECTIVE: Estimate the prevalence of human immunodeficiency virus (HIV) infection and Treponema pallidum in Argentine female sex workers (FSW), and describe the sociodemographic characteristics of this population group associated with HIV transmission. METHODS: A cross-sectional study and convenience sampling were conducted in FSW over 18 years of age in nine Argentine cities from October 2006 to December 2009. A total of 1 255 women participated in this study. A group of FSW was especially trained to invite other women to participate in the workshops and undergo screening for HIV and T. pallidum. RESULTS: The most noteworthy socioepidemiological characteristics of the FSW included a high percentage of sexual abuse, limited condom use with noncommercial sex partners, and a high percentage of violence. HIV prevalence was 2% (25/1 255, 95% confidence interval [95% CI]:1.2-2.8) and T. pallidum prevalence was 22.4% (245/1 094; 95% CI: 19.9-24.9). In the city of La Plata, HIV prevalence in FSW was significantly lower compared to that of other regions of the country (0.3% vs. 2.7%, P < 0.05, respectively). CONCLUSIONS: The lower HIV prevalence and the higher rate of condom use reported by the women from La Plata surveyed suggest that the presence of a health center for FSW has a direct influence on reducing risky behavior and, consequently, HIV infection. The creation of "friendly" health centers like the one already in this city contributes to providing a comprehensive response to the problems faced by these women and encourages use of the health system. It therefore helps reverse their vulnerability and higher risk of contracting HIV and other sexually transmitted infections.

Host genetic factors associated with symptomatic primary HIV infection and disease progression among Argentinean seroconverters.

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.

Prevalencia de la infección por el VIH y de Treponema pallidum en mujeres trabajadoras sexuales de Argentina / Prevalence of HIV infection and Treponema pallidum in Argentine female sex workers

OBJETIVO: Estimar la prevalencia de infección por el virus de la inmunodeficiencia humana (VIH) y de Treponema pallidum en mujeres trabajadoras sexuales (MTS) de Argentina, y describir las características sociodemográficas de este grupo de población asociadas a la transmisión del VIH. MÉTODOS: Entre octubre de 2006 y diciembre de 2009 se realizó un estudio de corte transversal y un muestreo por conveniencia en MTS mayores de 18 años de nueve ciudades de Argentina. Un total de 1 255 mujeres participaron en este estudio. Se capacitó especialmente a un grupo de MTS para convocar a las otras mujeres a participar en talleres y a realizarse el diagnóstico del VIH y T. pallidum. RESULTADOS: Las características socio-epidemiológicas más destacadas de las MTS incluyeron un alto porcentaje de abuso sexual, escaso uso de preservativos con parejas sexuales no comerciales y un alto porcentaje de situaciones de violencia. La prevalencia del VIH fue de 2 por ciento (25/1 255, intervalo de confianza de 95 por ciento [IC95 por ciento]:1,2-2,8) y la de T. pallidum, de 22,4 por ciento (245/ 1 094, IC95 por ciento: 19,9-24,9). En las MTS de la ciudad de La Plata, la prevalencia del VIH fue significativamente más baja comparada con las participantes del resto del país (0,3 por ciento vs 2,7 por ciento, P < 0,05, respectivamente). CONCLUSIONES: La menor prevalencia del VIH y la mayor tasa de uso de preservativos informadas por las mujeres encuestadas de La Plata sugieren que la presencia de un lugar de atención sanitaria para MTS influye directamente en la disminución de sus conductas de riesgo y, por ende, en la infección por el VIH. La creación de centros de salud "amigables", como el que ya hay en dicha ciudad, contribuye a dar una respuesta integral al problema que enfrentan estas mujeres; asimismo, favorece su acercamiento al sistema de salud y contribuye así a revertir su situación de mayor vulnerabilidad y mayor riesgo frente al VIH y otras infecciones de transmisión sexual.

OBJECTIVE: Estimate the prevalence of human immunodeficiency virus (HIV) infection and Treponema pallidum in Argentine female sex workers (FSW), and describe the sociodemographic characteristics of this population group associated with HIV transmission. METHODS: A cross-sectional study and convenience sampling were conducted in FSW over 18 years of age in nine Argentine cities from October 2006 to December 2009. A total of 1 255 women participated in this study. A group of FSW was especially trained to invite other women to participate in the workshops and undergo screening for HIV and T. pallidum. RESULTS: The most noteworthy socioepidemiological characteristics of the FSW included a high percentage of sexual abuse, limited condom use with noncommercial sex partners, and a high percentage of violence. HIV prevalence was 2 percent (25/1 255, 95 percent confidence interval [95 percent CI]:1.2-2.8) and T. pallidum prevalence was 22.4 percent (245/1 094; 95 percent CI: 19.9-24.9). In the city of La Plata, HIV prevalence in FSW was significantly lower compared to that of other regions of the country (0.3 percent vs. 2.7 percent, P < 0.05, respectively). CONCLUSIONS: The lower HIV prevalence and the higher rate of condom use reported by the women from La Plata surveyed suggest that the presence of a health center for FSW has a direct influence on reducing risky behavior and, consequently, HIV infection. The creation of "friendly" health centers like the one already in this city contributes to providing a comprehensive response to the problems faced by these women and encourages use of the health system. It therefore helps reverse their vulnerability and higher risk of contracting HIV and other sexually transmitted infections.