First Author | Akatsu C | Year | 2016 |
Journal | J Exp Med | Volume | 213 |
Issue | 12 | Pages | 2691-2706 |
PubMed ID | 27810925 | Mgi Jnum | J:237518 |
Mgi Id | MGI:5812845 | Doi | 10.1084/jem.20160560 |
Citation | Akatsu C, et al. (2016) CD72 negatively regulates B lymphocyte responses to the lupus-related endogenous toll-like receptor 7 ligand Sm/RNP. J Exp Med 213(12):2691-2706 |
abstractText | Toll-like receptor 7 (TLR7) plays an essential role in development of systemic lupus erythematosus by co-stimulating B cells reactive to the endogenous TLR7 ligand Sm/ribonucleoprotein (RNP), a crucial lupus self-antigen. However, how the TLR7-mediated autoimmune response is regulated is not yet known. In this study, we demonstrate that CD72, an inhibitory B cell co-receptor known to prevent development of lupus, recognizes Sm/RNP at the extracellular C-type lectin-like domain (CTLD) and specifically inhibits B cell response to Sm/RNP. Moreover, the CTLD of CD72c, a lupus-susceptible allele, binds to Sm/RNP less strongly than that of lupus-resistant CD72a Reduced binding of CD72c is supported by x-ray crystallographic analysis that reveals a considerable alteration in charge at the putative ligand-binding site. Thus, CD72 appears to specifically inhibit B cell response to the endogenous TLR7 ligand Sm/RNP through CTLD-mediated recognition of Sm/RNP, thereby preventing production of anti-Sm/RNP antibody crucial for development of lupus. |