新生儿Fc受体
跨细胞
抗体
MHC I级
受体
免疫球蛋白G
化学
细胞生物学
碎片结晶区
主要组织相容性复合体
免疫系统
生物
免疫学
生物化学
内吞作用
作者
Dilip K. Challa,Ramraj Velmurugan,Raimund J. Ober,E. Sally Ward
出处
期刊:Current Topics in Microbiology and Immunology
日期:2014-01-01
卷期号:: 249-272
被引量:42
标识
DOI:10.1007/978-3-319-07911-0_12
摘要
The neonatal Fc receptor, FcRn, is related to MHC class I with respect to its structure and association with β2microglobulin (β2m). However, by contrast with MHC class I molecules, FcRn does not bind to peptides, but interacts with the Fc portion of IgGs and belongs to the Fc receptor family. Unlike the 'classical' Fc receptors, however, the primary functions of FcRn include salvage of IgG (and albumin) from lysosomal degradation through the recycling and transcytosis of IgG within cells. The characteristic feature of FcRn is pH-dependent binding to IgG, with relatively strong binding at acidic pH (<6.5) and negligible binding at physiological pH (7.3-7.4). FcRn is expressed in many different cell types, and endothelial and hematopoietic cells are the dominant cell types involved in IgG homeostasis in vivo. FcRn also delivers IgG across cellular barriers to sites of pathogen encounter and consequently plays a role in protection against infections, in addition to regulating renal filtration and immune complex-mediated antigen presentation. Further, FcRn has been targeted to develop both IgGs with extended half-lives and FcRn inhibitors that can lower endogenous antibody levels. These approaches have implications for the development of longer lived therapeutics and the removal of pathogenic or deleterious antibodies.
科研通智能强力驱动
Strongly Powered by AbleSci AI