In:
The Journal of Immunology, The American Association of Immunologists, Vol. 176, No. 4 ( 2006-02-15), p. 2122-2133
Abstract:
We investigated the role of B cell Ag presentation in homeostasis of the memory B cell compartment in a mouse model where a conditional allele for the β-chain of MHC class II (MHC-II) is deleted in the vast majority of all B cells by cd19 promoter-mediated expression of Cre recombinase (IA-B mice). Upon T cell-dependent immunization, a small number of MHC-II+ B cells in IA-B mice dramatically expanded and restored normal albeit delayed levels of germinal center (GC) B cells with an affinity-enhancing somatic mutation to Ag. IA-B mice also established normal levels of MHC-II+ memory B cells, which, however, subsequently lost MHC-II expression by ongoing deletion of the conditional iab allele without significant loss in their number. Furthermore, in vivo Ag restimulation of MHC-II− memory B cells of IA-B mice failed to cause differentiation into plasma cells (PCs), even in the presence of Ag-specific CD4+ T cells. In addition, both numbers and Ag-specific affinity of long-lived PCs during the late post-GC phase, as well as post-GC serum affinity maturation, were significantly reduced in IA-B mice. These results support a notion that MHC-II-dependent T cell help during post-GC phase is not absolutely required for the maintenance of memory B cell frequency but is important for their differentiation into PCs and for the establishment of the long-lived PC compartment.
Type of Medium:
Online Resource
ISSN:
0022-1767
,
1550-6606
DOI:
10.4049/jimmunol.176.4.2122
Language:
English
Publisher:
The American Association of Immunologists
Publication Date:
2006
detail.hit.zdb_id:
1475085-5
