MHC class II and negative regulators of hematopoiesis.
HLA-DR antigens a side from their antigen-presenting function have recently been shown to allow for transmembrane signaling. Findings in several models suggest that such a signaling function may occur in hematopoietic tissues. Signals generated via HLA-DR result in upregulation of tumor necrosis factor alpha (TNF-alpha) and nitric oxide as well as an enhanced expression of Fas and its natural ligand (Fas-L), all molecules associated with programmed cell death (apoptosis). While a role of HLA-DR in hematopoietic failure remains hypothetical, the data presented here can be accommodated into a model of hematopoietic failure initiated by HLA-DR mediated signals.
Deeg
H J
HJ
Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
Lesnikov
V
V
D000818:Animals; D006684:HLA-DR Antigens / Q000276:immunology*; D006410:Hematopoiesis / Q000276:immunology*; D006801:Humans; D009569:Nitric Oxide / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D006684:HLA-DR Antigens; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide