| First Author | Honjo K | Year | 2012 |
| Journal | Proc Natl Acad Sci U S A | Volume | 109 |
| Issue | 39 | Pages | 15882-7 |
| PubMed ID | 22984178 | Mgi Jnum | J:190117 |
| Mgi Id | MGI:5448095 | Doi | 10.1073/pnas.1206567109 |
| Citation | Honjo K, et al. (2012) Altered Ig levels and antibody responses in mice deficient for the Fc receptor for IgM (FcmuR). Proc Natl Acad Sci U S A 109(39):15882-7 |
| abstractText | Cell surface Fc receptor for IgM antibody (FcmuR) is the most recently identified member among FcRs. We determined the cellular distribution of mouse FcmuR and the functional consequences of Fcmr disruption. Surface FcmuR expression was restricted to B-lineage cells, from immature B to plasma cells, except for a transient down-modulation during germinal center reactions. Fcmr ablation had no significant effect on overall B- and T-cell development, but led to a reduction of marginal zone B cells and an increase in splenic B1 B cells. Preimmune serum IgM in mutant mice was significantly elevated as were natural autoantibodies. When immunized with live attenuated pneumococci, mutant mice mounted robust antibody responses against phosphorylcholine, but not protein, determinants compared with wild-type mice. By contrast, upon immunization with a hapten-carrier conjugate, nitrophenyl-coupled chicken gamma-globulin (NP-CGG), the mutant mice had a diminished primary IgG1 response to both NP and CGG. These findings suggest that FcmuR has an important role in IgM homeostasis and regulation of humoral immune responses. |
