CD99 (E2) up-regulates α 4β 1-dependent T cell adhesion to inflamed vascular endothelium under flow conditions
✍ Scribed by Ghislaine Bernard; Vincent Raimondi; Isabelle Alberti; Monique Pourtein; John Widjenes; Michel Ticchioni; Alain Bernard
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 154 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0014-2980
No coin nor oath required. For personal study only.
✦ Synopsis
CD99/E2 is an integral transmembrane protein which forms, together with Xga, a distinct family whose genes are located in the pseudoautosomal region. The number of T cells that firmly bound to vascular endothelial cells under physiological shear stress increased 2-14-fold upon CD99 stimulation, and bound cells became much more resistant to detachment forces and spread. T cell arrest occurred within 1 min and was dependent on the alpha4beta1-VCAM-1 pathway. In contrast, the alphaLbeta2-ICAM-1 pathway remained unactivated. This was observed with T cell lines and with activated peripheral blood lymphocytes, and was limited within the resting peripheral CD4+ T cells to the memory subset, while virgin cells were unaffected. This discloses a stepwise regulation of the T cell extravasation cascade.