Fas antigen expression on CD34+ human marrow cells is induced by interferon gamma and tumor necrosis factor alpha and potentiates cytokine-mediated hematopoietic suppression in vitro

摘要: Activation of Fas antigen, a cell surface receptor molecule, by its ligand results in transduction signal for death. The system has been implicated target recognition, clonal development immune effector cells, and termination the cellular response. antigen expression on lymphocytes is regulated interferon gamma (IFN gamma) tumor necrosis factor alpha (TNF alpha), cytokines that also have inhibitory effects hematopoiesis. We investigated human marrow cells activation hematopoiesis vitro. Freshly isolated immature hematopoietic as defined CD34 marker, did not express at levels detectable fluorescent staining. CD34+ which include progenitors stem showed low culture, even presence growth factors. Stimulation TNF IFN markedly increased cells. Anti-Fas antibody, mimics action putative ligand, enhanced gamma- alpha-mediated suppression colony formation bone (BM) dose-dependent manner. This effect require accessory Colony from mature (CD34+ CD38+) CD38-) progenitor long-term culture initiating were susceptible to anti-Fas antibody alpha. Apoptosis assays performed total BM induced programmed death cells.(ABSTRACT TRUNCATED AT 250 WORDS)