First Author | Svensson MN | Year | 2015 |
Journal | Proc Natl Acad Sci U S A | Volume | 112 |
Issue | 48 | Pages | E6644-53 |
PubMed ID | 26627255 | Mgi Jnum | J:228325 |
Mgi Id | MGI:5706693 | Doi | 10.1073/pnas.1514191112 |
Citation | Svensson MN, et al. (2015) Murine germinal center B cells require functional Fms-like tyrosine kinase 3 signaling for IgG1 class-switch recombination. Proc Natl Acad Sci U S A 112(48):E6644-53 |
abstractText | Switched antibody classes are important for efficient immune responses. Aberrant antibody production to otherwise harmless antigens may result in autoimmunity. The protein kinase fms-like tyrosine kinase 3 receptor (Flt3) has an important role during early B-cell development, but the role of Flt3 in peripheral B cells has not been assessed before. Herein we describe a previously unappreciated role for Flt3 in IgG1 class-switch recombination (CSR) and production. We show that Flt3 is reexpressed on B-cell lymphoma 6(+) germinal center B cells in vivo and following LPS activation of peripheral B cells in vitro. Absence of Flt3 signaling in Flt3 ligand-deficient mice results in impaired IgG1 CSR and accumulation of IgM-secreting plasma cells. On activated B cells, Flt3 is coexpressed and functions in synergy with the common-gamma chain receptor family. B cells from Flt3 ligand-deficient mice have impaired IL-4R signaling, with reduced phosphorylation of signal transducer and activator of transcription (Stat) 6, and demonstrate a failure to initiate CSR to IgG1 with low expression of gamma1 germ-line transcripts, resulting in impaired IgG1 production. Thus, functional synergy between Flt3 and IL-4R signaling is critical for Stat-mediated regulation of sterile gamma1 germ-line transcripts and CSR to IgG1. |