title: Cutting edge: in the absence of regulatory T cells, a unique Th cell population expands and leads to a loss of B cell anergy.
abstract: The absence of regulatory T cells (Tregs) results in significant immune dysregulation that includes autoimmunity. The mechanism(s) by which Tregs suppress autoimmunity remains unclear. We have shown that B cell anergy, a major mechanism of B cell tolerance, is broken in the absence of Tregs. In this study, we identify a unique subpopulation of CD4(+) Th cells that are highly supportive of Ab production and promote loss of B cell anergy. Notably, this novel T cell subset was shown to express the germinal center Ag GL7 and message for the B cell survival factor BAFF, yet failed to express markers of the follicular Th cell lineage. We propose that the absence of Tregs results in the expansion of a unique nonfollicular Th subset of helper CD4(+) T cells that plays a pathogenic role in autoantibody production.
authors.affiliation: Division of Allergy/Immunology, Department of Pediatrics, Medical College of Wisconsin, Children's Research Institute, Milwaukee, WI 53226, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Leonardo
authors.forename: Jessica L
authors.initials: JL
authors.lastname: De Santis
authors.forename: Laurent P
authors.initials: LP
authors.lastname: Malherbe
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Gauld
mesh_terms: D000818:Animals; D016175:B-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D019070:Cell Lineage / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D017635:Clonal Anergy / Q000235:genetics / Q000276:immunology*; D017637:Clonal Deletion / Q000235:genetics / Q000276:immunology*; D018920:Coculture Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000473:pathology*