Anti-CD4 antibodies in exposed seronegative adults and in newborns of HIV type 1-seropositive mothers: A follow-up study

In this work, an ELISA for the quantitative determination of IgG anti-CD4 a utoantibodies was validated and utilized in the follow-up of two cohorts of HIV-l-exposed seronegative subjects. A serum with an arbitrarily assigned concentration of 100,000 units/ml was used as a reference, and the detectio n limit, inter- and intraassay variability, and analytical recovery were ca lculated. The study subjects included adults sexually exposed to HIV-1-infe cted partners and the newborns of HIV-1(+) mothers who seroreverted by 18 m onths of age. Some of these individuals were studied over an 18- to 24-mont h period, The detection limit of the assay was 2000 AU/ml, Intra- and inter assay variability was, respectively, 3.92 and 3.90%, Analytical recovery in an assay in which a fixed amount of anti-CD4 antibodies was added to diffe rent samples was 98%, A proportion of adults (16 of 47, 34.0%) and babies ( 12 of 27, 44.4%) had significantly higher concentrations of anti-CD4 antibo dies. Among them, 8 adults maintained the same concentration as that found in the first determination; on the other hand, 12 babies born to seronegati ve mothers showed a significant increase in the concentration of anti-CD4 a ntibodies during their first months of life. In conclusion, anti-CD4 antibo dies can be measured using a validated ELISA, They represent a serologic tr ait that is quantitatively conserved in HIV-l-exposed seronegative adult in dividuals and is actively acquired by newborns to HIV+ mothers.