Cell-mediated and humoral immune responses in children infected with human immunodeficiency virus during the first four years of life.

OBJECTIVES: To determine whether cell-mediated and humoral immune responses to recall antigens develop in children infected with the human immunodeficiency virus (HIV) and, if so, whether these responses are retained.
METHODS: Children infected with HIV and uninfected children born to mothers infected with HIV were compared with respect to lymphoproliferative responses to recall antigens and protective levels of antibody to bacterial toxoids during the first 4 years of life.
RESULTS: Children infected with HIV who were enrolled in a prospective study of the natural history of the infection were relatively normal (1) in their lymphoproliferative responses to diphtheria toxoid, tetanus toxoid, and Candida, and (2) in their ability to make protective diphtheria and tetanus antitoxins during the first 2 years of life. During the next 2 years, attrition was noted in both lymphoproliferative and humoral responses. Attrition in response was not necessarily correlated with declining numbers of helper T cells.
CONCLUSIONS: These results suggest that both cellular and humoral immune responses develop early in life in most children infected with HIV, while they remain relatively well both clinically and immunologically. Previously reported severe immune deficits in these children were probably attributable to advanced clinical disease when they were first studied.