ABSTRACT
The paper summarizes the results of HIV-1 serotyping by using 56 positive sera collected in the territory of the Republic of Tajikistan (RT) from intravenous drug users (IVDU). It was made by solid-phase ELISA based on synthetic peptides, mimicking different variants of the apical epitope of the HIV-1 gp120 V3-loop. Two types of conjugates, those specific to human IgG and IgA, were used to detect the immune complexes. Serotypes, as determined according to IgG and IgA-based ELISA, coincided, however, the latter were proven to be more suitable for serotyping. There is a high level of HIV-1 serotype heterogeneity among IVDU in RT; altogether, 4 serotypes were identified, i.e. B (10%), B+A/C (18%), A/C (20%) and A/C+B (52%). The modern serotype HIV-1 diversity in RT resembles the epidemiologic situation in the territory of the former USSR as observed in the late 80-ies-early 90-ies of the last century.