Functional expression of CD134 by neutrophils.
CD134 (OX40) is a member of the tumor necrosis factor (TNF) receptor superfamily expressed on activated T cells. Here, we show that human peripheral blood neutrophils express CD134. Activation of CD134 by soluble CD134 ligand (OX40 ligand/gp34) resulted in delayed caspase-3 activation and consequently in delayed neutrophil apoptosis in vitro. Moreover, CD134 ligand, like G-CSF, maintained anti-apoptotic Mcl-1 levels and inhibited cleavage of the pro-apoptotic Bcl-2 family members Bid and Bax in these cells, suggesting that CD134-mediated signals block apoptosis pathways proximal to mitochondria activation. In conclusion, CD134 regulates neutrophil survival, suggesting that this molecule does not only contribute to adaptive but also to innate immune responses.
Baumann
Ralf
R
Department of Pharmacology, University of Bern, Friedbühlstrasse 49, CH-3010 Bern, Switzerland.
Yousefi
Shida
S
Simon
Dagmar
D
Russmann
Stefan
S
Mueller
Christoph
C
Simon
Hans-Uwe
HU
D017209:Apoptosis / Q000502:physiology; D051023:BH3 Interacting Domain Death Agonist Protein; D002352:Carrier Proteins / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D006801:Humans; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D009363:Neoplasm Proteins / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology* / Q000502:physiology; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2; D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor / Q000819:agonists / Q000276:immunology*; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D002352:Carrier Proteins; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor; C505716:TNFRSF4 protein, human; D051028:bcl-2-Associated X Protein; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases