Possible role of interleukin-10 in autoantibody production and in the fate of human cord blood CD5+ B lymphocytes.
Mononuclear cell subsets in 25 human umbilical cord blood samples and 10 healthy adults were studied. We found a decreased percentage of CD3+ cells, CD8+ cells and gammadelta T cells in cord blood compared with blood from healthy adults. The CD16+56+ and CD19+CD5+ phenotypes were overexpressed in cord blood. We then measured spontaneous gene expression and the production of interleukin-10 in mononuclear cells from cord blood and adult subjects. Although we found no difference between cord blood cells and those from healthy adults, a tendency towards spontaneous interleukin-10 production was observed in cord blood. Phorbol 12-myristate 13-acetate stimulation revealed that, among lymphocytes, cord blood B cells are the main cellular source of interleukin-10. Finally, we found no evidence of augmented spontaneous apoptosis but an increased bcl-2 gene expression in non-T cells from cord blood. Interleukin-10 might protect CD19+CD5+ B cells from apoptosis by inducing bcl-2 and promoting autoantibody production in this B-cell subpopulation.
Villaseñor-Bustamante
S
S
Department of Immunology and Rheumatology, Instituto Nacional de la Nutrición Salvador Zubirán.
Alvarado-De La Barrera
C
C
Richaud-Patin
Y
Y
Martínez-Ayala
H
H
Llorente
L
L
D000328:Adult; D001323:Autoantibodies / Q000096:biosynthesis / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D018956:CD5 Antigens; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D016753:Interleukin-10 / Q000276:immunology*; D008211:Lymphocyte Cooperation; D018655:Lymphocyte Count; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
D001323:Autoantibodies; D018956:CD5 Antigens; D016692:Receptors, Antigen, T-Cell, gamma-delta; D016753:Interleukin-10