Association between KIR genotypes and HLA-B alleles on viral load in Southern Brazilian individuals infected by HIV-1 subtypes B and C.

There is a great variety of HIV-1 subtypes circulating in Brazil, including subtype C, whose prevalence is on the rise, particularly in the southern region. Many host and viral genetic factors may be involved in this trend. We evaluated the influence of human leukocyte antigen (HLA) class I alleles and killer-cell immunoglobulin-like receptor (KIR) genotypes on viral set point and T-CD4(+) parameters in 84 treatment-naïve HIV-1-positive individuals. Frequency data in the infected group were compared to data of 548 healthy control subjects. Individuals with the KIR AA genotype had a higher viral load (VL) than individuals with the KIR Bx genotype. The HIV-1 group was subdivided into three subgroups according to HLA-B allele presence: those with protection to disease alleles (HLA-B(+)), accelerated disease progression alleles (HLA-B(-)), or neither (HLA-B(o)) were grouped. We observed a significant effect of the HLA-B allele presence on VL. The HLA-B(+) group had significantly lower VL than the HLA-B(-) group and trended toward a lower VL than the HLA-B(o) group. There were significant differences between groups expressing extreme VL values: KIR-AA+HLA-B(-) vs. KIR Bx+HLA-B(+) and KIR-AA+HLA-B(o)vs. KIR Bx+HLA-B(+). The relationship of KIR/HLA host genetics with slow HIV disease progression in southern Brazil may be useful for vaccine developers, epidemiologists, and clinicians.

Pre-exposure and postexposure prophylaxes and the combination HIV prevention methods (The Combine! Study): protocol for a pragmatic clinical trial at public healthcare clinics in Brazil.

INTRODUCTION: Few results from programmes based on combination prevention methods are available. We propose to analyse the degree of protection provided by postexposure prophylaxis (PEP) for consensual sexual activity at healthcare clinics, its compensatory effects on sexual behaviour; and the effectiveness of combination prevention methods and pre-exposure prophylaxis (PrEP), compared with exclusively using traditional methods. METHODS AND ANALYSIS: A total of 3200 individuals aged 16 years or older presenting for PEP at 5 sexually transmitted disease (STD)/HIV clinics in 3 regions of Brazil will be allocated to one of two groups: the PEP group-individuals who come to the clinic within 72 h after a sexual exposure and start PEP; and the non-PEP group-individuals who come after 72 h but within 30 days of exposure and do not start PEP. Clinical follow-up will be conducted initially for 6 months and comprise educational interventions based on information and counselling for using prevention methods, including PrEP. In the second study phase, individuals who remain HIV negative will be regrouped according to the reported use of prevention methods and observed for 18 months: only traditional methods; combined methods; and PrEP. Effectiveness will be analysed according to the incidence of HIV, syphilis and hepatitis B and C and protected sexual behaviour. A structured questionnaire will be administered to participants at baseline and every 6 months thereafter. Qualitative methods will be employed to provide a comprehensive understanding of PEP-seeking behaviour, preventive choices and exposure to HIV. ETHICS AND DISSEMINATION: This study will be conducted in accordance with the resolution of the School of Medicine Research Ethics Commission of Universidade de São Paulo (protocol no. 251/14). The databases will be available for specific studies, after management committee approval. Findings will be presented to researchers, health managers and civil society members by means of newspapers, electronic media and scientific journals and meetings.