Accelerated emigration of B lymphocytes in the Xid mouse.
The B cell receptor is required for the emigration of newly generated B lymphocytes and for their maintenance in the periphery. A specific maintenance defect was noted in fraction I (IgDhighIgMlow) B cells in Xid mice (which harbor a mutation in Btk). Although Bcl-2 levels in fractions I and II (IgDhighIgMhigh) are equivalent in normal and Xid B cells, a novel peak of Bcl-2low fraction III (IgDlowIgMhigh) B cells was noted in the Xid mouse. Since this B cell population resembled bone marrow immature B cells, we examined the emigration of newly formed B cells in normal and Xid mice. These studies revealed the accelerated emigration of newly formed Xid B cells. We conclude that distinct Btk-independent and Btk-dependent signals mediate emigration and maintenance events during peripheral B cell maturation.
Cariappa
A
A
Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA 02129, USA.
Kim
T J
TJ
Pillai
S
S
D000077329:Agammaglobulinaemia Tyrosine Kinase; D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000276:immunology; D001402:B-Lymphocytes / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002465:Cell Movement / Q000235:genetics* / Q000276:immunology*; D002469:Cell Separation; D004195:Disease Models, Animal; D007153:Immunologic Deficiency Syndromes / Q000201:enzymology / Q000235:genetics* / Q000473:pathology*; D051379:Mice; D008808:Mice, Inbred CBA; D008817:Mice, Mutant Strains; D011505:Protein-Tyrosine Kinases / Q000172:deficiency / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D013234:Stem Cells / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D014960:X Chromosome / Q000276:immunology
D019253:Proto-Oncogene Proteins c-bcl-2; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625951:Btk protein, mouse