[Immunologic profile of HIV-2 seropositive African individuals (follow-up)]. / Perfil imunológico de indivíduos africanos HIV-2 seropositivos (follow-up).

ABSTRACT

PIP: In 1986, a total of 4372 persons were included in an HIV-2 seroepidemiological study covering the whole of Guinea-Bissau. An 8.5% incidence of HIV-2 infection was revealed by the enzyme-linked immunosorbent assay (ELISA) confirmed by Western Blot and/or RIPA. Only 4 cases of HIV-1 seropositivity were found. Annual follow-up of 78 seropositive (e died of AIDS) and 320 seronegative individuals in 1988, 1989, 1990, and 1991 was initiated. In the present investigation, a total of 70 individuals were included: 19 were seropositive (6 with double reactivity) and 51 were seronegative. During this period there were 3 seroconversion cases among seronegative persons, and the appearance of double reactivity in 3 previously HIV-2 positive cases. The reexamination of sera before seroconversion indicated reactivity to the core proteins and in 3 cases to GP-160 or GP-140 surface glycoproteins. The average values of immunoglobulins increased, but the beta-2 microglobulin, and cytomegalovirus antibodies (CMV) did not differ in the sera of 1250 decreased patients compared with seronegative persons. In seropositives, a progressive diminution of the CD4 lymphocyte values and of the T4/T8 (CD4/CD8) ratio was observed which was much more evident in HIV-2 monoreactive patients than in double reactive patients. The interpretation of HIV-1 and HIV-2 double reactivity whether the result of a double infection or of an intermediate variant of the virus between HIV-1 and HIV-2 has not been reconciled with these results. These findings indicate that the variants responsible for double reactivity are less pathogenic, less adapted to the human host, and less developed phylogenetically.