Pathogenicity of HIV in lymphatic organs of patients with AIDS.

HIV antigens were searched for in the thymus, lymph nodes, bone marrow, and spleen of AIDS patients, by means of immunofluorescence technique. Human IgG against HIV and monoclonal antibodies against viral gag P24 protein yielded strong cytoplasmic fluorescence of cells in sections of the thymus, lymph nodes and spleen. Some cells containing HIV antigens were morphologically multinucleated giant cells. They reacted with monoclonal antibodies against helper/inducer T-cells (OKT4+), and were complexed with antibody or with complement as demonstrated by double-staining immunofluorescence technique. A large number of inflammatory cells infiltrated the thymus in areas containing cells expressing HIV antigens. These studies demonstrated an association of HIV virus with cytopathic and immunopathogenic reactions in lymphatic organs of AIDS patients, and are consistent with previous results, as well as indicative of a primary aetiologic role for the virus.