Selective induction of CD8+CD4- thymocyte apoptosis mediated by the B-subunit of Escherichia coli heat-labile enterotoxin.
Receptor-binding by the B-subunit of Escherichia coli heat-labile enterotoxin (EtxB) induces apoptosis of peripheral CD8(+), but not CD4(+) T-cells. Given that peripheral CD8(+) and CD4(+) T cells arise from a common developmental pathway in the thymus, we investigated the effects of EtxB on different thymocyte populations. We show that the acquisition of sensitivity to EtxB-mediated cell death arises following transition of CD4(+)CD8(+) double positive cells into the CD4(-)CD8(+) pathway. Maturation of T cells into CD4(-)CD8(+) single positive cells is associated with upregulated expression of receptors for EtxB.
Salmond
Robert J
RJ
Department of Pathology and Microbiology, School of Medical Sciences, University of Bristol, University Walk, Bristol, BS8 1TD, UK.
Williams
Rachel
R
Hirst
Timothy R
TR
Williams
Neil A
NA
D000818:Animals; D017209:Apoptosis; D001427:Bacterial Toxins / Q000276:immunology* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology*; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D004768:Enterotoxins / Q000276:immunology* / Q000378:metabolism; D004926:Escherichia coli / Q000276:immunology*; D029968:Escherichia coli Proteins; D006162:Guanylate Cyclase / Q000378:metabolism; D051379:Mice; D000074261:Receptors, Enterotoxin; D050705:Receptors, Guanylate Cyclase-Coupled; D018000:Receptors, Peptide / Q000378:metabolism
D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D018000:Receptors, Peptide; C027538:heat-labile enterotoxin, E coli; D020169:Caspases; D006162:Guanylate Cyclase; D000074261:Receptors, Enterotoxin; D050705:Receptors, Guanylate Cyclase-Coupled