Differential contribution of Wiskott-Aldrich syndrome protein to selective advantage in T- and B-cell lineages.
Somatic mosaicism because of in vivo reversion has been recently reported in a small number of patients affected with Wiskott-Aldrich syndrome (WAS). Flow cytometry analysis of WAS protein (WASP) expression has shown that these patients carried revertant cells only among T lymphocytes. Here, we have used high-resolution capillary electrophoresis to analyze genomic DNA from highly purified cells of one of these patients and detected revertant sequences also within the B-cell fraction. The demonstration of revertant cells among both T and B lymphocytes in this patient is consistent with the reversion event having occurred in a common lymphoid progenitor. However, although WASP-expressing T cells showed selective advantage and were readily detectable in the periphery of the mosaic patient, revertant B lymphocytes remained below the detection threshold of flow cytometry. These findings suggest that, contrary to T cells, differentiation and survival of B lymphocytes is minimally dependent on WASP.
D001402:B-Lymphocytes / Q000276:immunology*; D041321:Chromosomes, Human, X / Q000235:genetics; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D011506:Proteins / Q000235:genetics* / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014923:Wiskott-Aldrich Syndrome / Q000235:genetics / Q000276:immunology*; D051316:Wiskott-Aldrich Syndrome Protein
D011506:Proteins; C495767:WAS protein, human; D051316:Wiskott-Aldrich Syndrome Protein; D004247:DNA