Co-stimulation of antigen-specific CD4 T cells by 4-1BB ligand.

摘要: 4-1BB is a member of the TNF receptor family predominantly expressed on activated T cells, and binds an inducible ligand found B macrophages dendritic cells. Whereas ligation has been shown to enhance response purified CD8 cells mitogens, augment NK activity generation cytotoxic lymphocytes in vivo, there are little direct data action during CD4 responses. Using pigeon cytochrome c-presenting fibroblast antigen-presenting transfected with (4-1BBL), we show that engaging naive promotes proliferation, cell cycle progression IL-2 secretion, suppresses death, all similar extent as B7-1 engagement CD28. In addition, 4-1BBL synergizes B7 ICAM proliferation when antigen limiting. alone, greater B7, also augmented secretion resting antigen-experienced typified by helper clones, whereas short-term effector showed levels cytokine regardless whether was engaged. A major role augmenting IFN-gamma, IL-4 or IL-5 not demonstrated. Blocking studies presenting participates promoting production confirming can play antigen-specific