Analyses of functional antibody responses in HIV-1-infected individuals after vaccination with rgp160

Long-term immunotherapy in HIV infection, combined with short-term antiretroviral treatment

Forty asymptomatic HIV-infected individuals with CD4+ lymphocyte levels above 400 × 106/1 were immunized over 5 years with recombinant envelope glycoprotein gp160 (rgp160). After 5 years there was a trend towards more nonprogressors in the immunized group as compared to the matched controls. Since immunizations could activate HIV, the first 6 immunizations were followed by 2 weeks of zidovudine or placebo, double-blind. The viral load did not change during the first 6 months and was not different from that of the matched controls after 5 years. The best effect on CD4+ lymphocyte development was seen in individuals with a high viral load randomized to rgp160+zidovudine and in individuals with a low viral load randomized to rgp160+placebo. We conclude that rgp160 is safe and results in temporarily improved CD4+ development. Concomitant antiviral treatment might be of benefit, especially in patients with a more advanced disease and can today be given with more effective combinations.

Evaluation of the serologic response against two consensus V3 loop peptides from human immunodeficiency virus-1 in Cuban patients

OBJECTIVES

A retrospective study was conducted to evaluate the antibody response of Cuban patients infected with human immunodeficiency virus (HIV)-1 against two consensus peptides from the third variable domain (V3) loop of glycoprotein gp120.

METHODS

The study included sera from 10 individuals at different stages of disease. Two 15-meric synthetic peptides designed from a consensus sequence, belonging to group B or C of HIV-1, were used to determine antibody titers and avidity indexes in an indirect enzyme-linked immunoassay.

RESULTS

A high reactivity against both peptides was detected, with 80% of the sera reacting with at least one of the peptides. The antibody titers and avidity indexes did not correlate with disease progression. Additionally, for one of the patients from whom the virus had been isolated, a higher avidity index was found against the homologous peptide.

CONCLUSIONS

This study showed high reactivity against two consensus peptides from the V3 loop of gp120 among patients with HIV. Large scale studies are needed to determine whether the titers or avidity of anti-V3 antibodies, at the early stages of infection, are predictive of disease progression. Both peptides are candidates for inclusion in experimental vaccines.

Seroreactivity to HIV-1 V3 subtypes A to H peptides of Argentinian HIV-positive sera

Serologic assays could be useful for determining circulating subtypes in different geographic regions. A total of 175 serum samples from the same number of Argentinian HIV-infected patients from Buenos Aires and Rosario were tested against a panel of peptides representing V3 consensus subtypes A through H. A V3 peptide enzyme immunoassay was used for screening the sera. Most sera were reactive with peptides representing subtypes B (58.28%), F (13.14%), and A (8.57%). Cross-reactivity between the remainder of the peptides was observed. Genotypes of eight patients from Rosario were determined and compared with serotyping. Results showed that seven of eight genotyped patients reacted with their respective consensus B peptide and one reacted with consensus B and F. V3 peptide serology proved to be useful for determining HIV-1 clades circulating in Argentina.