Distinct mechanisms for rescue from apoptosis in Ramos human B cells by signaling through CD40 and interleukin-4 receptor: role for inhibition of an early response gene, Berg36.
AffiliationInfection and Immunity Research group, King's College London, GB.
MetadataShow full item record
AbstractThe role of interleukin-4 (IL-4) and CD40 signaling in negative regulation of apoptosis in human Ramos B cells induced in response to different agents was investigated. CD40 ligation protected cells from apoptosis induced by calcium ionophore through an initial, rapid and apparently Bcl-2-independent mechanism, associated with up-regulation of Bcl-XL. However, rescue from apoptosis induced by inhibition of macromolecular synthesis required several hours of prior stimulation with CD40 ligand/antibody and was accompanied by up-regulation of Bcl-2. In contrast, IL-4 did not up-regulate Bcl-2 or Bcl-XL and did not inhibit apoptosis induced by inhibitors of macromolecular synthesis. However, IL-4 did protect Ramos cells from apoptosis induced by calcium ionophore and this effect was accompanied by inhibition of ionophore-induced expression of an immediate early gene encoding a 36-kDa zinc-finger protein, Berg36. Antisense blockade of Berg36 expression partially inhibited ionophore-induced apoptosis to an extent commensurate with the level of IL-4 protection, implicating Berg36 function as a requirement for apoptosis induced through calcium signaling and as a target for IL-4 through which this cytokine inhibits apoptosis in Ramos B cells. These distinct mechanisms for rescue from apoptosis by CD40 and IL-4 may help explain the co-operative roles of these T cell-derived signals for B cell survival.
CitationDistinct mechanisms for rescue from apoptosis in Ramos human B cells by signaling through CD40 and interleukin-4 receptor: role for inhibition of an early response gene, Berg36. 1996, 26 (10):2356-63 Eur. J. Immunol.
JournalEuropean Journal of Immunology
- Ectopic expression of Bcl-2, but not Bcl-xL rescues Ramos B cells from Fas-mediated apoptosis.
- Authors: Alam MK, Davison S, Siddiqui N, Norton JD, Murphy JJ
- Issue date: 1997 Dec
- B cell early response gene expression coupled to B cell receptor, CD40 and interleukin-4 receptor co-stimulation: evidence for a role of the egr-2/krox 20 transcription factor in B cell proliferation.
- Authors: Newton JS, Li J, Ning ZQ, Schoendorf DE, Norton JD, Murphy JJ
- Issue date: 1996 Apr
- Germinal center-derived signals act with Bcl-2 to decrease apoptosis and increase clonogenicity of drug-treated human B lymphoma cells.
- Authors: Walker A, Taylor ST, Hickman JA, Dive C
- Issue date: 1997 May 15
- Distinct mechanisms for rescue from apoptosis in Ramos human B cells by signalling through CD40 and interleukin-4 receptor: role for inhibition of an early response gene, Berg36.
- Authors: Ning ZQ, Norton JD, Li J, Murphy JJ
- Issue date: 1997 May
- Ligation of CD40 potentiates Fas-mediated activation of the cysteine protease CPP32, cleavage of its death substrate PARP, and apoptosis in Ramos-Burkitt lymphoma B cells.
- Authors: An S, Yap D, Knox KA
- Issue date: 1997 Nov 1