In:
Blood, American Society of Hematology, Vol. 89, No. 4 ( 1997-02-15), p. 1288-1298
Kurzfassung:
The recent finding of somatically mutated μ heavy chain transcripts in human peripheral blood (PB) B lymphocytes suggests that T-dependent B-cell memory might not be restricted to class-switched cells. We provide here evidence that IgM-only PB B cells are likely to be the IgM-expressing counterpart of classical (IgM−IgD−) memory B cells in humans. As shown by molecular single cell analysis, most IgM-only cells carry mutated V region genes, like class-switched cells. Although both subsets represent populations of nonactivated, resting cells, they express higher levels of Ig mRNA than naive (IgM+IgD+) B cells. IgM-only and class-switched cells are CD38−CD77−, and mostly CD23−, thus neither resembling germinal center nor naive B cells. Because many IgM-expressing B cells located in secondary lymphoid tissues resemble IgM-only PB B cells in terms of cell phenotype, we propose that the human lymphoid system contains a large compartment of IgM-expressing memory cells. Moreover, these cells seem to represent the nonmalignant counterparts of IgM-expressing tumor cells in sporadic Burkitt's lymphoma, MALT lymphoma, monocytoid B-cell lymphoma, and diffuse large-cell lymphoma that were found to harbor somatically mutated V genes.
Materialart:
Online-Ressource
ISSN:
1528-0020
,
0006-4971
DOI:
10.1182/blood.V89.4.1288
Sprache:
Englisch
Verlag:
American Society of Hematology
Publikationsdatum:
1997
ZDB Id:
1468538-3
ZDB Id:
80069-7
