Immunological comparison of HIV-1-, HIV-2- and dually-reactive women delivering in Abidjan, Côte d'Ivoire

Objectives.
To compare the basic immunological changes induced by HIV-1 and HIV-2 infection and to assess the immune status of subjects serologically reactive to both HIV-1 and HIV-2 (dually-reactive).

Design.
Immune parameters were studied cross-sectionally in women delivering in Abidjan, Côte d'lvoire, West Africa, where HIV-1 and HIV-2 are endemic. In this area, a significant number of sera from infected individuals are reactive to both HIV-1 and HIV-2.

Subjects and methods.
Two hundred and twenty-eight women delivering in a major maternity clinic were screened for HIV-1 and HIV-2 using an enzyme-linked immunosorbent assay. Seropositivity was confirmed by Western blot. The immune parameters studied were CD4+ and CD8+ lymphocyte subsets, immunoglobulin (lg) serum levels, neopterin and β2-microglobulin (β2M) serum levels.

Results.
Similar but less pronounced immune changes were present in HIV-2-reactive subjects compared with HIV-1− and dually-reactive subjects. The observed differences between the HIV-seropositive groups could not be explained by differences in age or disease stage but paralleled differences in the frequency of persistent generalized lymphadenopathy (PGL). The intermediate immune profile of HIV-2-reactives (between seronegatives and HIV-1− and dually-reactives) was most clearly reflected by the number of CD8+ lymphocytes, the CD4:CD8 ratio and the LgG serum level. Median neopterin and β2M levels, though significantly increased in all HIV-seropositive groups, did not differ significantly between HIV-2-, HIV-1− and dually-reactives.

Conclusions.
HIV-2 infection is associated with typical HIV-related immunological changes. Immunologically, dually-reactives resemble HIV-1-reactives more closely than HIV-2-reactive subjects.