To rule out whether protection against HIV infection in HESN participants could be the result of CCR5 receptor mutation, we compared heterozygous (CCR5/ccr5) and homozygous (ccr5 /ccr5) mutation in HESN participants with HIV-1+

partners and the HIV-1+ group. The heterozygous mutation was present in seven HESN participants (30%) in one (4%) of the HIV-1+ partners and in four of the HIV-1+ group (4%). Homozygous mutation Birinapant research buy associated with protection against infection was not found in any of the three groups. We found a significant increase in KIR3DS1 receptor (homozygous or heterozygous for this allele) in the HESN group compared with HIV-1+ partners (OR = 24, P = 0·000003) and HIV-1+ group (OR = 8·15, P = 0·00066). These results suggest that the sole presence of KIR3DS1 could have a protective role in HIV-1 infection

BMN 673 supplier in HESN individuals. Similar results were observed when we analysed the combination of KIR3DS1 with HLA-Bw4 alleles in HESN individuals versus their HIV-1+ partners (OR = 15·24, P = 0·0003) and the HIV-1+ group (OR = 6·86; P = 0·0001; Table 1). Ravet et al.[15] reported in some exposed uninfected (EUs) the concomitant expression of lowered inhibitory KIR3DL1 transcript levels and high activating KIR3DS1 levels resulted a KIR3DS1/KIR3DL1 radio that may confer an enhanced activating NK cell repertoire profile to these EUs. The specific combination of both activating and inhibitory KIR3DS1/KIR3DL1 and HLA-Bw4 alleles has been associated with delayed progression to AIDS based on epidemiological studies.[9-11] Carrington et al.[16] indicate that it is also possible that the various KIR3DL1/KIR3DS1 molecules might differ in their binding affinity Selleckchem 5-Fluoracil for their HLA ligand, which may in turn influence AIDS progression. HLA ligand binding for KIR3DS1 is still controversial. Carr et al.[7] found that the soluble KIR3DS1-Ig fusion proteins did not bind to Epstein–Barr virus-transformed B lymphoid cell lines

transfected with HLA-Bw4-80I or 80T allotypes, suggesting that KIR3DS1 does not recognize HLA-Bw4 ligand. This may be peptide-dependent. Conversely, Guerini et al.[17] only observed this significant increase in HESN individuals who were homozygous KIR3DS1 in combination with Bw4 with respect to HIV-1+ individuals. Homozygosity for KIR3DS1 was present at low percentages in all populations analysed in our study. However, the frequency of heterozygosity for KIR3DS1 is found in high levels in the normal population, indicating an important Amerindian influence in northern Argentina, as pointed out by some authors.[3, 18] When we analysed just the Bw4 alleles (homozygous or heterozygous) we found no differences between the studied groups, although Melo da Silva et al.[19] reported a significant association between HLA-Bw4 and low levels of viraemia in HIV-infected Brazilian patients. On the other hand, Welzel et al.