Tumour necrosis factor-alpha-induced apoptosis in cord blood T lymphocytes: involvement of both tumour necrosis factor receptor types 1 and 2.
Cord blood T cells are much more likely to be induced to apoptosis in vitro than adult T cells. Nevertheless, the expression of Fas is markedly lower on cord blood lymphocytes than on peripheral blood lymphocytes. In the current investigation, we determined the capacity of tumour necrosis factor-alpha (TNF-alpha) to induce apoptosis in human naïve T cells in cord blood, and assessed the roles of two distinct TNF receptors (TNFRs) in mediating death signals. After activation, cord blood T cells were sensitive to TNF-alpha-induced apoptosis, and interleukin 2 (IL-2) could prevent this apoptotic response. Both TNFR1 (p55) and TNFR2 (p75) expressed on activated cord blood T cells were able to transmit apoptotic signals. Moreover, a synergistic effect was observed by a combination of TNFR1- and TNFR2-signals. Additionally, CD4(+) T cells showed higher sensitivity to TNFR-mediated apoptosis than CD8(+) T cells. These data suggest that TNF-alpha probably is a mediator of apoptosis in cord blood T cells in vivo and may contribute to the low incidence of graft-versus-host disease in cord blood transplantation.
Yang
Y C
YC
School of Medical Technology, College of Medicine, National Taiwan University, Taiwan, Republic of China.
Hsu
T Y
TY
Chen
J Y
JY
Yang
C S
CS
Lin
R H
RH
D015703:Antigens, CD / Q000276:immunology; D017209:Apoptosis / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D018929:Cell Culture Techniques; D004306:Dose-Response Relationship, Immunologic; D005312:Fetal Blood / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D007376:Interleukin-2 / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D018124:Receptors, Tumor Necrosis Factor / Q000276:immunology*; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*
D015703:Antigens, CD; D007376:Interleukin-2; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D014409:Tumor Necrosis Factor-alpha