Alloantigenicity of human endothelial cells. 1. Frequency and phenotype of human T helper lymphocytes that can react to allogeneic endothelial cells.
To determine the relative ability of allogeneic endothelial cells to stimulate helper T lymphocytes (HTL), human PBMC or purified T cells were incubated in conventional lymphocyte microcultures or in limiting dilution microcultures with allogeneic human umbilical vein endothelia (HUVE), with cytokine-treated allogeneic HUVE, or with allogeneic peripheral blood monocytes. These cultures were tested for IL-2 production as an index of HTL stimulation. Dose-response studies in conventional lymphocyte cultures indicated that allogeneic monocytes were better than allogeneic HUVE at stimulating IL-2 production. Limiting dilution analyses revealed that untreated HUVE and TNF-treated HUVE stimulated small numbers of HTL (approximately 1 HTL/30,000 PBMC), whereas 5 to 10 times more HTL were stimulated by IFN-gamma-treated HUVE and 10 to 20 times more HTL were stimulated by allogeneic monocytes. Serologic deletion studies revealed that most of the high frequency HTL responding to IFN-gamma-treated HUVE were CD4+, whereas most of the low frequency HTL responding to nontreated HUVE or to TNF-treated HUVE were CD8+. Interestingly, mAb to MHC class I and class II molecules, which significantly impaired HUVE-induced proliferation, caused little interference with HUVE-induced IL-2 production. Finally, polymerase chain reaction analysis demonstrated that untreated allogeneic HUVE cells could stimulate PBMC to produce mRNA for IFN-gamma, as well as for IL-2. These data demonstrate the following hierarchy of allogeneic stimulatory capacity for human HTL: monocytes greater than IFN-gamma-treated HUVE much greater than TNF-treated HUVE = nontreated HUVE. Further, these data suggest that non-activated allogeneic endothelial cells can initiate immune responses by inducing IL-2 and IFN-gamma. Because IFN-gamma can induce MHC class II expression by the endothelial cells, this could recruit large numbers of CD4+ T cells for IL-2 production.
Department of Surgery, Ohio State University College of Medicine, Columbus 43210.
P W
PW
Adams
H S
HS
Lee
W J
WJ
Waldman
D D
DD
Sedmak
C J
CJ
Morgan
J S
JS
Ward
C G
CG
Orosz
D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016827:CD8 Antigens / Q000032:analysis; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000276:immunology*; D006681:HLA-D Antigens / Q000032:analysis; D015395:Histocompatibility Antigens Class I / Q000032:analysis; D006801:Humans; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000494:pharmacology; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D016827:CD8 Antigens; D016207:Cytokines; D006681:HLA-D Antigens; D015395:Histocompatibility Antigens Class I; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma