title: Genetic control of immune responses to the 18-kDa protein of Mycobacterium leprae. Different TH1 subsets may be involved in proliferative and delayed-type hypersensitivity responses.
abstract: In vitro and in vivo responses to the 18-kDa protein of Mycobacterium leprae have been analysed in different strains of mice. Lymphocytes from BALB/cJ (H-2d), BALB.B (H-2b), B10.BR (H-2k), and B10.M (H-2f) mice primed with 18-kDa protein yielded high T cell proliferative responses, while those from C57BL/10J (H-2b) mice yielded lower responses. Both H-2 and non-H-2 genes contributed to the magnitude of responsiveness. F1 mice from high and low responder strains showed high responsiveness to the 18-kDa protein. Supernatants from lymph node cell cultures prepared from 18-kDa protein-immunised BALB/cJ, B10.BR, and C57BL/10J mice contained IL-2 but no IL-4, indicating that activated T cells from both high and low responder mice were of a TH1 phenotype. Cell cultures from low responder C57BL/10J mice produced less IL-2 than those from high responders. The low responsiveness to the 18-kDa protein in proliferative assays might be due to a low frequency of antigen-specific T cells in the C57BL/10J mouse strain. BALB/cJ, C57BL/10J, and F1 (BALB/cJ x B10.BR) mouse strains were tested for in vivo DTH reactions to the 18-kDa protein. All strains, including C57BL/10J, were high DTH responders. Although DTH effector cells and 18-kDa protein-specific proliferative T cells belong to the TH1 subset, our data comparing high and low responder status indicate that distinct TH1 subpopulations are stimulated in response to the 18-kDa protein of M. leprae.
authors.affiliation: Department of Molecular Medicine, School of Medicine, University of Auckland, New Zealand.
authors.forename: B T
authors.initials: BT
authors.lastname: Bäckström
authors.forename: D P
authors.initials: DP
authors.lastname: Harris
authors.forename: R L
authors.initials: RL
authors.lastname: Prestidge
authors.forename: J D
authors.initials: JD
authors.lastname: Watson
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division; D002478:Cells, Cultured / Q000187:drug effects; D006968:Hypersensitivity, Delayed / Q000235:genetics* / Q000276:immunology; D007376:Interleukin-2 / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D008213:Lymphocyte Activation / Q000235:genetics*; D051379:Mice; D008815:Mice, Inbred Strains; D009166:Mycobacterium leprae / Q000737:chemistry; D009169:Mycobacterium tuberculosis / Q000737:chemistry; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; D007376:Interleukin-2; D015847:Interleukin-4