Format

Send to

Choose Destination
J Leukoc Biol. 2008 Oct;84(4):1183-91. doi: 10.1189/jlb.1207829. Epub 2008 Jul 1.

Signaling through ephrin-A ligand leads to activation of Src-family kinases, Akt phosphorylation, and inhibition of antigen receptor-induced apoptosis.

Author information

1
Ullevaal University Hospital, 0407 Oslo, Norway.

Abstract

Eph receptor tyrosine kinases and ephrins play important roles in diverse biological processes such as migration, adhesion, and angiogenesis. Forward and reverse signaling has been reported in receptor- and ligand-bearing cells. The ligands can be divided into the transmembrane ephrin-B family and the GPI-anchored ephrin-A family. Here, we show expression of ephrin-A ligands on CD4+ T cells cultured in medium with human serum and the T cell line Jurkat TAg and on cells isolated from patients with T cell lymphomas and T cell leukemias. Functional role and identification of proteins involved in ephrin-A signaling were investigated here in the T cell line Jurkat TAg. Signaling through ephrin-A induces phosphorylation of several proteins, including the Src kinases Lck and Fyn. In addition, PI-3K is activated, shown by induced phosphorylation of the Akt kinase. An ephrin-A signaling complex could be isolated, containing several phosphorylated proteins including Lck and Fyn. Interestingly, we show that signaling through ephrin-A in Jurkat TAg cells, initiated by interaction with the EphA2 receptor, leads to inhibition of activation-induced cell death. To conclude, ephrin-A signaling in Jurkat TAg cells leads to induced phosphorylation of several proteins including Lck, Fyn, and Akt. A consequence of ephrin-A signaling is inhibition of antigen receptor-induced apoptosis.

PMID:
18593733
DOI:
10.1189/jlb.1207829
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley Icon for Norwegian BIBSYS system
Loading ...
Support Center