01512nas a2200277   4500000000100000008004100001260001600042653002400058653001900082653004400101653001600145653001100161653002100172653002400193653001200217653002600229653002500255100001500280700001500295700001100310245014200321300001100463490000800474520073800482022001401220       1987                            d  c1987 Jan 0110aAntigens, Bacterial10aConcanavalin A10aDose-Response Relationship, Immunologic10aGlycolipids10aHumans10aImmune Tolerance10aIn Vitro Techniques10aleprosy10aLymphocyte Activation10aMycobacterium leprae1 aPrasad H K1 aMishra R S1 aNath I00aPhenolic glycolipid-I of Mycobacterium leprae induces general suppression of in vitro concanavalin A responses unrelated to leprosy type.  a239-440 v1653 a<p>Using a costimulant assay, in vitro Con A responses of patients across the leprosy spectrum were found to be markedly suppressed by phenolic glycolipid-I (PGL-I), a unique antigen of M. leprae. The degree of inducible suppression as well as the number of leprosy patients showing suppression of mitogenic responses was higher with PGL-I as compared with integral M. leprae (p less than 0.05 to less than 0.01). Both untreated lepromatous (60%) as well as tuberculoid leprosy (67%) patients showed significant suppression ranging from 13 to 64% and 12 to 79%, respectively. Thus, PGL-I appears to have a universal suppressive effect on Con A responses and is unlikely to play a central role in determining the leprosy spectrum.</p>  a0022-1007