[In situ characterization of lymphocyte subsets in various types of leprosy]

Using monoclonal antibodies and immunoperoxidase technique,the numbers and distribution of T lymphocyte subsets in the skin lesions of various types of leprosy (including TT 6 cases,BT 4 cases,BB 1 case,BL 6 cases,and LL 13 cases) were determined and compared with each other.We found large amount of Leu 4 cells al the periphery of the TT granuloma,while the least number of this cells scattered loosely and admixed with the leprous cells in LL.The OKT4/OKT8 ratio was much higher in the TT polar type,with gradually declining towards another pole of the spectrum in LL type,e.g.,TT (1.76) > BT(1.13) > BB (1.1) > BL(1.03) > LL(0.45).It showed that OKTB cells were relatively increased in LL.The pattern of segregation of OKT4 and OKT8 cells at the periphery of the granuloma were shown in TT as well as in BT,but was better developed in the former.All these may reflect immunohistologically a cell-mediated immune response seen in both TT and BT.In addition,we found infiltration of OKT4 and OKT8 cells in the epidermis as well as in the hair follicles,which were easily seen in TT and BT.Infiltration of OKT8 cells were more encountered in LL,and their significance was also discussed.