Premium
B cells extract and present immobilized antigen: implications for affinity discrimination
Author(s) -
Batista Facundo D.,
Neuberger Michael S.
Publication year - 2000
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1093/emboj/19.4.513
Subject(s) - antigen , biology , internalization , b cell receptor , antigen presentation , immune system , microbiology and biotechnology , antibody , cell , b cell , biochemistry , immunology , t cell
Binding of antigen to B‐cell antigen receptor (BCR) leads to antigen internalization and presentation to T cells, a critical process in the initiation of the humoral immune response. However, antigen internalization has been demonstrated for soluble antigen, in vivo antigen is often encountered in insoluble form or tethered to a cell surface. Here, we show that not only can B cells internalize and present large particulate antigen (requiring a signalling‐competent BCR to drive antigen uptake), but they can also extract antigen that is tethered tightly to a non‐internalizable surface. The form in which the antigen is displayed affects the B cell's ability to discriminate antigen–BCR affinity. Thus, arraying an antigen on a particle or surface allows efficient presentation of low affinity antigens. However, the presentation efficiency of antigen arrayed on an internalizable particle plateaus at low affinity values. In contrast, extraction and presentation of antigen from a non‐internalizable surface depends on antigen–BCR affinity over a wide affinity range. The results have implications for understanding both the initiation and affinity maturation of the immune response.