T-cell depletion of spleen in patients with longstanding lepromatous leprosy.

In 8 autopsied lepromatous patients the spleen was examined histopathologically and their differential cell population was counted in subcapsular area, red pulp and white pulp. There was considerable reduction of lymphocytes and well marked increase in macrophages and plasma cells in the thymus dependent white pulp. In the subcapsular area and the red pulp, although there was an increase in plasma cells and macrophages no significant reduction of lymphocytes was recorded. Therefore, it is suggested that in lepromatous leprosy there is a selective reduction in the number of T lymphocytes.