%A Makonkawkeyoon S %A Kasinrerk W %A Dettrairat S %A Vithayasai V %T Immunologic defects in leprosy patients. I. Evidence of immune aberration of suppressor-T lymphocytes in lepromatous leprosy %0 Journal Article %D 1990 %J International Journal of Leprosy and other Mycobacterial Diseases %P 0148-916X %V 58 %N 2 %X Immunoregulation in various types of leprosy patients was evaluated in vitro using peripheral blood mononuclear leukocytes (PBML) stimulated with phytohemagglu-tinin-P (PHA-P) or concanavalin A (ConA) for a cell-mediated immune (CMI) assay or pokeweed mitogen (PWM) for a humoral-mediated immune (HMI) assay. The immune responses were evaluated by a lymphocyte transformation test (LTT) and lymphocyte-mediated cytotoxicity (LMC) for the immunoregulation of CMI, and a reverse hemolytic plaque assay for measuring the plaque-forming cells (PFC) and a sandwich ELISA for measuring IgG concentrations for the immunoregulation of HMI.
In LTT with PHA-P or ConA, the mean of the normal controls was not significantly different f rom the means of the untreated LL, BL, BB, BT, and TT leprosy patients. However, a wide variation of LTT results f rom BT to LL patients was noted: the LTT results of TT patients and normal controls were less variable. A similar pattern of immune responses was noted when studied by LMC in untreated LL, BL, BB, BT, and TT leprosy patients and normal controls. When the untreated patients and normal controls were studied for PFC, using PBML stimulated with PWM, a very similar pattern of PFC was obtained with the different types of leprosy patients.
The immunoregulatory role of lymphocytes in leprosy patients was further evaluated by cell mixing cultures. ConA-stim-ulated PBML f rom lepromatous leprosy patients were mixed with normal PBML and then stimulated with PHA-P. The immune regulation was then measured by LMC. Untreated BL/LL patients having a bacterial index (BI) of 3+ or more had significantly less suppressive activity than treated BL/ LL patients having a BI of less than 3 + , less than treated TT patients, and less than normal controls.
The activity of suppressor-T lymphocytes f rom untreated LL patients was further evaluated by the isolation of CD8+ T cells or ConA-sheep erythrocyte (SRBC) rosetted T cells f rom PBML of these patients and normal controls. The CD8+ T cells or ConA-SRBC rosetted T cells were cultured in various percentages with normal PBML and then stimulated with PWM. The immunoregulation of these T-cell populations was measured by quantitative determination of the PFC, using a reverse hemolytic plaque assay, or by quantitation of IgG with an ELISA. The CD8+ T cells and ConA-SRBC rosetted T cells f rom these LL patients showed significantly less suppressive activities in all of the tested cell concentrations when compared with normal controls.