title: Polarized helper-T-cell responses against Leishmania major in the absence of B cells.
abstract: B-cell-to-T-cell signaling can shape helper T (Th) cell responses. During infection with Leishmania major, Th response is critical in determining the outcome of disease. Resistance depends on the generation of a protective Th1 response, while susceptibility is mediated by the generation of a Th2 response. In this study, we determined whether B cells are required for the development of polarized Th1 and Th2 responses during infection with L. major. Mice lacking B cells due to disruption of the immunoglobulin M locus (microMT) were infected with L. major, and disease progression and Th cell development were assessed. On the genetically resistant C57BL background, both wild-type and microMT mice controlled the infection and mounted a Th1 response. On the genetically susceptible BALB/c background, both wild-type and microMT mice were susceptible to infection and generated Th2 responses. Thus, during L. major infection, neither direct antigen presentation or costimulation by B cells nor antibody-mediated effector functions are essential for the development of polarized Th responses.
authors.affiliation: Committee on Immunology, The University of Chicago, Illinois 60637, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Brown
authors.forename: S L
authors.initials: SL
authors.lastname: Reiner
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology* / Q000473:pathology; D020022:Genetic Predisposition to Disease / Q000276:immunology; D007113:Immunity, Innate; D018320:Leishmania major / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D008231:Lymphopenia / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology