Cross-Reactivity to V3 Peptides of gp120 of HIV-1 in plasma samples of patients infected with subtype B or Local BF Recombinant Forms in Argentina.

JC AMBROSIONI CZYRKO, R. BARRAL, C. ACUIPIL, G. ANDREANI, Y. ROMER, D. RABINOVICH, L. MARTÍNEZ PERALTA.

Seattle

Congreso; Aids Vaccine 2007.; 2007

Aids Vaccine initiative

Objective: Studíes performed on molecular epídemiology of HIV-1 in Argentina have shown the prevalence of subtype B as well as BF recombinant forms; nearly in 50% proportion each in the metropolilan populalion. However, no sludies have been performed about lhe possibility lo recognize differentially lhe V3 zone of gp120 by antibodies. The goal of lhis work was lo analyze humoral cross-reaclivity lo V3 peplides between subtype B and BF recombinanl forms. Methods: Plasma samples of 60 HIV-1 infecled palienls were analyzed. Informed consenl was oblained from the palienls. Sequences were characlerized from plasma using genome sequencing of lhe poi and V3 (C2C3) regions. An in-house EIA assay was performed using commercial anli-human IgG labelled with peroxidase (Dakopatts, Sweden). Peplides used corresponded lo lhe 15 cenlral amínoacids of the V3 loop of gp120 from sublype B: MN and SF2; subtype F1 and a consensus peplide from Argentinean BF recombinants sequences. This peptide was designed taking inlo account sequences oblained in our laboralory from plasma samples of patienls infecled with B/F recombinants. For slatistical analysis Wilcoxon rank sum tesl and chi square lest were used. Results: Thirty four palienls were infecled with subtype B and 26 with BIF recombinanls. In 8 palienls there was no agreement in the result obtained in V3 and poi regions, bul V3 specificity was laken inlo accounl for the reaclivily analysis. The median of oplical density was higher to MN peptide for samples of patients infected with both subtypes B and BF (p0.05). In average, there was a low reaclivity to SF2 and to F1 peptides, similar to negative controls. Conclusion: No differences were found in the reaclivity lo peptides B and BF in patients infected with subtypes B or BF. Bolh groups had higher response to MN peptide. These resu~s confirm previous studies performed in plasma samples of patients whose subtype was not so extensively characterized. The implicalions of this study could be important for studies on preventive vaccines