Resting B cells expand a CD4+CD25+Foxp3+ Treg population via TGF-beta3.
Regulatory T cells (Treg) play critical roles in maintaining tolerance and preventing autoimmunity. It is not fully clear how these cells are generated and maintained. Here, we show that resting B cells are able to expand Treg. This expansion requires TGF-beta3 and signaling through the TCR and CD28. Upon activation, B cells express less TGF-beta3, which reduces their capacity to expand Treg and which also results in increased Treg death. This may ensure that B cells can function as potent professional antigen presenting cells during infections. However, in the absence of any infection, we find that B-cell-deficient microMT mice have decreased percentages of Treg in the periphery. Our data suggest that resting B cells, which may be presenting self-antigens to T cells, can expand and maintain specific Treg and thus might be involved in the prevention of autoimmunity.
Shah
Shivanee
S
Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL 60153, USA.
Qiao
Liang
L
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D018106:CD28 Antigens / Q000276:immunology* / Q000378:metabolism; D002478:Cells, Cultured; D018920:Coculture Techniques; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D011948:Receptors, Antigen, T-Cell / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D053782:Transforming Growth Factor beta3 / Q000378:metabolism*
D018106:CD28 Antigens; D011948:Receptors, Antigen, T-Cell; D053782:Transforming Growth Factor beta3