A comparative ultrastructural study of virions in human pre-AIDS and simian AIDS.

Virions resembling the AIDS-associated retroviruses HTLV-III and LAV were identified between pseudopods of dendritic reticulum cells in lymph nodes from 3 patients with prodromal AIDS. The virions are morphologically distinguishable from HTLV-I and HTLV-II and also from D-type retroviruses that are associated with the simian acquired immune deficiency syndrome. Budding forms resembling incomplete nucleoids of maturing D-type retrovirus were found in neutrophils in a lymph node from another patient with prodromal AIDS. The significance of these structures is unknown.