AEGiS-11IAC: Preferential recognition of V3 African sequences and relation with disease progression among Cuban HIV-positive individuals.

11th International AIDS Conference

Vancouver, British Columbia — July 7-12, 1996

Preferential recognition of V3 African sequences and relation with disease progression among Cuban HIV-positive individuals.

Int Conf AIDS 1996 Jul 7-12; 11:439 (abstract no. Pub.A.1010)
Lopez-Campistrous Ana, Reyes O, Garay H, Diaz H, Duarte C; Center for Genetic Engineering and Biotechnology, Havana, Cuba.

OBJECTIVE: To analyse the serological response in HIV-1 Cuban seropositive individuals against five synthetic V3 loop peptides, and to correlate it with the clinical stage of these subjects.

METHODS: 35-meric (spanning the whole V3 loop) and 15-meric (spanning the tip of the loop) peptides were prepared. Plasmas from 61 individuals were tested against sequences from the phenetic V3 classification group 1 (central sequence GPGQAF), group 9 (GPGRVF), group 10 (GPGRAF), group 18 (GLGQAL), and group 19 (GQGQAL). Antibody response was studied by enzyme linked immunosorbent assay (ELISA). Plates were coated with: i) 35-meric peptides, ii) bovine seroalbumin (BSA) conjugated 15-meric peptides (at 10 microgram/ ml) or, iii) BSA conjugated 15-meric peptides (at 2 microgram/ ml).

RESULTS: Among the samples analysed, the frequency of response was significantly higher (82, 72, or 45% of recognition; for i), ii), or iii) respectively) against the peptide with the central sequence GPGQAF (p less than or equal to 0.04). The 18, 28 and 57% of samples did not react while 65, 40 and 13% of them did, at least against two peptides for each coating condition respectively. Competition experiments suggested cross-reactive antibodies being the probable cause for the latter observation. The frequency of reactivity with V3 peptides was lower in the plasma from AIDS patients, in comparison with individuals in other stages (p less than or equal to 0.04).

CONCLUSIONS: The highest frequency of reactivity in Cuban plasmas is found against a peptide representing HIV-1 isolates from Central and Southern Africa, and India. The cross-reactivity between peptides in ELISA was lower when both 15-meric peptides and low coating concentration were used. Disease progression was inversely associated with anti-V3 responses.

Keywords: AEGIS, HIV Infections, Disease Progression, HIV Seropositivity, HIV-1, Acquired Immunodeficiency Syndrome, Peptides, Enzyme-Linked Immunosorbent Assay, Simian Acquired Immunodeficiency Syndrome, Negroid Race, Antibodies, Africa, Southern, India, Animal, Cattle, Human, ICA11

960707
PubA1010