An evaluation of the immune state in leprosy.

An evaluation of the immune state in leprosy was done by the application of a system of graft-versus-host reaction. Peripheral blood lymphocytes obtained from patients with different forms of leprosy and from normal healthy individuals were injected intravenously into the irradiated mice. The rate of blast transformation of the donor cells was measured by the radio-active thymidine uptake. The number of cells labelled with tritiated-thymidine was much higher in the normal individuals and patients with tuberculoid leprosy than in the patients with lepromatous leprosy with the borderline group placed in between the two. However, following successful treatment with DDS, an increased responsiveness and active DNA synthesis could be observed in the previously less responsive lepromatous lymphocytes.