Abstract

IgM is the first antibody to be produced in a humoral immune response and is a major isotope of natural antibodies and may play an important role in innate immunity. On the other hand, IgA is a secreted antibody at the mucosal membrane such as the gastrointestinal and respiratory tracts and protects from initial invasion of microbes. However, how these antibodies are involved in immunity has been poorly elucidated. We previously identified a novel Fc receptor for IgA and IgM, designated Fcalpha/mu receptor (Fcalpha/muR), whose gene is closely located at the polymeric immunoglobulin receptor (poly-IgR), also a receptor for IgA and IgM, in the Fc receptor gene cluster on the chromosome 1. In contrast to the the poly-IgR that is expressed on epithelial, but not hematopoietic, cells, Fcalpha/muR is constitutively expressed on the majority of B lymphocytes and macrophages in the spleen and at the center of the secondary lymphoid follicles. The Fcalpha/muR mediates endocytosis Staphylococcus aureus /anti-S. aureus IgM antibody immune complexes by B lymphocytes, for which the dileucine motif in the cytoplasmic tail of the mouse Fcalpha/muR is responsible. These results reveal a new mechanism in the primary stage of immune defense against microbes.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.