|
||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
J. Exp. Med.,
Volume 187, Number 8, April 20, 1998 1325-1334
By
From the Department of Microbiology and Immunology, University of North Carolina at Chapel Hill,
Chapel Hill, North Carolina 27599
Murine phosphatidyl choline (PtC)-specific B cells in normal mice belong exclusively to the
B-1 subset. Analysis of anti-PtC (VH12 and VH12/V
4) transgenic (Tg) mice indicates that exclusion from B-0 (also known as B-2) occurs after immunoglobulin gene rearrangement. This
predicts that PtC-specific B-0 cells are generated, but subsequently eliminated by either apoptosis or differentiation to B-1. To investigate the mechanism of exclusion, PtC-specific B cell
differentiation was examined in mice expressing the X-linked immunodeficiency (xid) mutation. xid mice lack functional Bruton's tyrosine kinase (Btk), a component of the B cell receptor signal transduction pathway, and are deficient in B-1 cell development. We find in C57BL/
6.xid mice that VH12 pre-BII cell selection is normal and that PtC-specific B cells undergo
modest clonal expansion. However, the majority of splenic PtC-specific B cells in anti-PtC
Tg/xid mice are B-0, rather than B-1 as in their non-xid counterparts. These data indicate that
PtC-specific B-0 cell generation precedes segregation as predicted, and that Btk function is required for efficient segregation to B-1. Since xid mice exhibit defective B cell differentiation,
not programmed cell death, these data are most consistent with an inability of PtC-specific B-0
cells to convert to B-1 and a single B cell lineage.
This article has been cited by other articles:
| TABLE OF CONTENTS |
|