[Study of T lymphocyte subpopulations in patients with leprosy, using incubation with theophylline]

T cells and the theophylline resistant cells (the-r, helper cells) in peripheral blood of patients with different forms of leprosy were studied. Active lepromatous patients (LL+) showed a significant decrease in T lymphocytes and the-r cells. Nevertheless, in LL+ developing a reactional episode of erythema nodosum (LL-ENL) a restoration in the level of the-r cells was observed. It is concluded that in LL+ patients the depression of T cells and the-r cells represents an imbalance in the T-T cellular cooperation with a defective cellular immune response. On the other hand, the recovery of the-r cells in LL-ENL support the hypothesis of a cell mediated immune mechanism in the immunopathology of this reactional episode.