Immunohistochemical studies of lymph nodes from LAS and AIDS patients.

Lymph nodes from eight LAS and six AIDS patients were studied by routine histology, immunohistochemistry, and ultraimmunohistochemistry. LAS lymph nodes show a peculiar follicular hyperplasia with a characteristic increase of proliferating dendritic and interdigitating reticulum cells. In AIDS, these cells are reduced and the expression of proliferation-associated antigens is diminished. The immunohistochemical analysis of dendritic and interdigitating reticulum cells and of proliferation-associated antigens in lymph nodes thus allows a clear distinction between LAS and AIDS and may have important prognostic implications.