02766nas a2200397   4500000000100000008004100001260001300042653001200055653002700067653002200094653002500116653001100141653003700152653001800189653001800207653001200225653002600237653000900263653002100272653002500293653002700318653002900345653001800374653005700392100002000449700001500469700001600484700001500500700001600515700001700531245024700548300001100795490000800806520154000814022001402354       1985                            d  c1985 Aug10aAnimals10aAntibodies, Monoclonal10aAntigens, Surface10aBinding, Competitive10aHumans10aImmunologic Deficiency Syndromes10aInterleukin-110aInterleukin-210aleprosy10aLymphocyte Activation10aMice10aMice, Inbred C3H10aMycobacterium leprae10aReceptors, Immunologic10aReceptors, Interleukin-210aT-Lymphocytes10aTumor Necrosis Factor Receptor Superfamily, Member 71 aMohagheghpour N1 aGelber R H1 aLarrick J W1 aSasaki D T1 aBrennan P J1 aEngleman E G00aDefective cell-mediated immunity in leprosy: failure of T cells from lepromatous leprosy patients to respond to Mycobacterium leprae is associated with defective expression of interleukin 2 receptors and is not reconstituted by interleukin 2.  a1443-90 v1353 a<p>Patients with lepromatous leprosy (LL) but not borderline tuberculoid leprosy (BT) have defective cell-mediated immune responses to Mycobacterium leprae, despite normal responses to other stimuli, as judged by in vivo skin testing and in vitro lymphocyte transformation. To investigate the basis of the immune defect in LL patients, we studied the ability of patient mononuclear leukocytes to produce interleukin 1 (IL 1) and interleukin 2 (IL 2) upon stimulation with M. leprae, and determined the ability of exogenous IL 1 and IL 2 to reconstitute the LL patient response to this antigen in vitro. Equal numbers of adherent non-T cells from LL and BT patients produced similar amounts of IL 1 upon challenge with M. leprae, and addition of IL 1 to the culture medium failed to reconstitute the response of lymphocytes from LL patients to M. leprae. On the other hand, T cells of LL patients failed to express receptors for IL 2 or to produce IL 2 in response to M. leprae, whereas similarly treated T cells of BT patients both expressed IL 2 receptors and produced IL 2. Finally, recombinant human IL 2 purified to homogeneity as well as crude supernatants of mitogen-activated lymphocytes failed to reconstitute the response of LL patients to M. leprae. These results suggest that T cells of LL patients fail to respond to M. leprae despite an ability to produce IL 1 and that their failure to express receptors for IL 2 may explain both defective proliferation and the failure of exogenous IL 2 to reconstitute the response.</p>  a0022-1767