TYPE-1-LIKE AND TYPE-2-LIKE LESIONAL SKIN-DERIVED MYCOBACTERIUM LEPRAE-RESPONSIVE T-CELL CLONES ARE CHARACTERIZED BY COEXPRESSION OF IFN-GAMMA TNF-ALPHA AND IL-4/IL-5/IL-13, RESPECTIVELY/

In an earlier study, we generated a large number of Mycobacterium lepr ae-responsive and M. leprae-nonresponsive T cell clones (TCC) from the lesional skin of immunologic unstable borderline leprosy patients, In that study, we divided TCC into type 1- and type 2-like on the basis of their IFN-gamma and IL-4 expression, To explore whether other cytok ines are coproduced along with IFN-gamma and IL-4, we investigated the secretion of a panel of other cytokines (TNF-alpha, IL-5, IL-6, IL-10 , and IL-13) by a large number of these TCC. Upon analysis of 139 M. l eprae-responsive TCC, we observed a positive correlation in the coprod uction of IFN-gamma/TNF-alpha (r = 0.81), and in that of IL-4/IL-5 (r = 0.83), IL-4/IL-13 (r = 0.80), and IL-5/IL-13 (r = 0.82). Polarized t ype 1-like TCC produced dominantly IFN-gamma/INF-alpha, and polarized type 2-like TCC predominantly IL-4/IL-5/IL-13. Most type 0-like TCC pr oduced both sets of cytokines. In contrast, type 1- and type 2-like su bsets of M. leprae-nonresponsive TCC (n = 58) did not show the same co expression of these cytokines. Furthermore, when the differential expr ession of a broad panel of cytokines by individual M. leprae-responsiv e TCC is considered, it appeared that additional phenotypes could be r ecognized, These results suggested that distinct isotypes of type 1- a nd type 2-like T cells, based on the secretion of a panel of cytokines , may reflect M. leprae-specific characteristics.