T cell reactivity against antigen 85 but not against the 18- and 65-kD heat shock proteins in the early stages of acquired immunity against Mycobacterium leprae.
T cell proliferation and interferon-gamma (IFN-gamma) production of peripheral blood mononuclear cells (PBMC) from 20 household contacts were tested against the 18- and 65-kD heat shock proteins from Mycobacterium leprae (ML18 and ML65 respectively) and antigen 85 from Myco. bovis bacille Calmette-Guérin (BCG) (Ag 85) during a 12-months follow-up study. Among the eight contacts that became positive, eight showed positive reactivity against Ag 85, 5/8 against ML65 and 4/8 against ML18 at the end of the study. Of the 16 contacts who were lepromin-positive either at first or second testing, all responded to Ag 85, 11 to ML 65, but only eight reacted to ML18 antigen. Contacts who were lepromin-positive at first testing developed responses to ML18 only at second testing. In contrast, among the four contacts that remained lepromin-negative during the follow up, three proliferated to Ag 85 either at first or second testing, but only one produced IFN-gamma against Ag 85 at the end of the study. These results demonstrated that T cell reactivity and particularly IFN-gamma secretion against Ag 85, but not against ML18 and ML65, might be a predominant mechanism in the early stages of acquired protective immunity against Myco. leprae.
Launois
P
P
Immunology Unit, Institut Pasteur de Dakar, Sénégal.
Niang N'Diaye
M
M
Sarthou
J L
JL
Drowart
A
A
Van Vooren
J P
JP
Cartel
J L
JL
Huygen
K
K
D000293:Adolescent; D000328:Adult; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology; D005260:Female; D006360:Heat-Shock Proteins / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007916:Lepromin / Q000032:analysis; D008213:Lymphocyte Activation; D008297:Male; D009166:Mycobacterium leprae / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; D007916:Lepromin; C071448:antigen 85B, Mycobacterium leprae; D007371:Interferon-gamma