title: The BH3-mimetic ABT-737 inhibits allogeneic immune responses.
abstract: Apoptosis controls the adaptive immune system through regulation of central and peripheral lymphocyte deletion. Therefore, substances that selectively interact with the intrinsic apoptosis pathway in lymphocytes offer unexplored opportunities to pharmacologically modulate the immune response. Here, we present evidence that the BH3-mimetic ABT-737 suppresses allogeneic immune responses. In vitro, ABT-737 prevented allogeneic T-cell activation, proliferation, and cytotoxicity by apoptosis induction, but without impairing the physiological functions of remaining viable T cells. In vivo, ABT-737 was highly selective for lymphoid cells and inhibited allogeneic T- and B-cell responses after skin transplantation. The immunosuppressive effect of ABT-737 was markedly increased in combination with low-dose cyclosporine A, as shown by the induction of long-term skin graft survival without significant inflammatory infiltrates in 50% of the recipients in an MHC class I single antigen mismatched model. Thus, pharmacological targeting of Bcl-2 proteins represents a novel immunosuppressive approach to prevent rejection of solid organ allografts.
authors: Institute of Physiology, University of Zürich, Switzerland.
authors: Pietro E
authors: PE
authors: Cippà
authors: Anna K
authors: AK
authors: Kraus
authors: Ilka
authors: I
authors: Edenhofer
authors: Stephan
authors: S
authors: Segerer
authors: Jin
authors: J
authors: Chen
authors: Martin
authors: M
authors: Hausmann
authors: Yang
authors: Y
authors: Liu
authors: Annick
authors: A
authors: Guimezanes
authors: Philip D
authors: PD
authors: Bardwell
authors: Rudolf P
authors: RP
authors: Wüthrich
authors: Thomas
authors: T
authors: Fehr