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Infect Immun ; 57(4): 1311-7, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2494115


The killing of Mycobacterium leprae by resting and gamma interferon (IFN-gamma)-activated macrophages in normal subjects and leprosy patients was assessed. Resting macrophages from normal individuals demonstrated the ability to kill M. leprae. For macrophages from tuberculoid patients, killing of M. leprae was only achieved in the presence of IFN-gamma, suggesting that initial T-cell activation occurs prior to the killing of M. leprae. In contrast, though activation with IFN-gamma rendered the lepromatous macrophages microbicidal, it failed to induce lymphocyte proliferation, suggesting a defect at either the antigen-presenting cell or the lymphocyte level or both. The concept that T-cell anergy is primarily due to lack of lymphokine generation was ruled out by our results, since responsiveness was restored in only a small proportion of lepromatous patients after exogenous lymphokine addition. In conclusion, this study demonstrated that killing and antigen presentation are two independent events. It appears that the ability of the macrophages per se to kill M. leprae may be of greater importance than lymphocyte-mediated activation for protection against M. leprae infection.

Células Apresentadoras de Antígenos/imunologia , Antígenos de Bactérias/imunologia , Atividade Bactericida do Sangue , Hanseníase/imunologia , Ativação de Macrófagos , Mycobacterium leprae/imunologia , Animais , Comunicação Celular , Concanavalina A , Antígenos HLA-DR/análise , Humanos , Interferon gama/farmacologia , Hanseníase/sangue , Hanseníase/microbiologia , Leucócitos Mononucleares/fisiologia , Linfocinas/fisiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Mycobacterium leprae/crescimento & desenvolvimento , Receptores Fc/análise , Superóxido Dismutase , Linfócitos T/imunologia , Linfócitos T/fisiologia
Scand J Immunol ; 28(2): 211-6, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3045948


A critical problem in leprosy is the relative deficiency of antigen-specific T cell-mediated immunity. We were successful in detecting a significant response to viable M. leprae in mononuclear cells isolated from the lymph nodes of lepromatous leprosy patients in contrast to the apparent M. leprae-specific energy seen in the peripheral blood. This observation suggests that antigen-reactive lymphocytes are generated in the lymph nodes of lepromatous patients but the inability to detect them in the circulation may be due either to a different processing and presentation of mycobacterial antigens within the peripheral blood and lymph node compartments or to a selective sequestration of lymphocytes within the lymph node.

Antígenos de Bactérias/análise , Hanseníase/sangue , Linfonodos/citologia , Mycobacterium leprae/imunologia , Linfócitos T/microbiologia , Humanos , Ativação Linfocitária , Tuberculina
Int. j. lepr ; 19(2): 165-172, Apr.-Jun. 1951. tab
Artigo em Inglês | SES-SP, HANSEN, SESSP-ILSLACERVO, SES-SP | ID: biblio-1227411


1- The rersults of the lepromin test in contacts with defatted lepromin are given. 2- Adult contacts who gave positive reactions to lepromin were positive for bacilli in the skin, whereas adult contacts who were negative to lepromin were negative for bacilli. 3- Of 13 children who were positive for bacilli in the skin, 8 were positive and 5 negative to lepromin. 4- The degree of the positive lepromin reaction is compared with the number of bacilli found, and is shown to be in inverse proportion. 5- The significance of the positive bacteriological and immunological findings is discussed, and a case is made out for the assumption that these contacts were in stage which is the forerunner of the phase at which primary lesions develop. 6- The development of lesions in contacts is discussed.

Antígeno de Mitsuda/classificação , Antígeno de Mitsuda/imunologia , Hanseníase