Agonist-induced T cell receptor down-regulation: molecular requirements and dissociation from T cell activation

✍ Scribed by Mariolina Salio; Salvatore Valitutti; Antonio Lanzavecchia

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 460 KB
• Volume: 27
• Category: Article
• ISSN: 0014-2980
• DOI: 10.1002/eji.1830270726

✦ Synopsis

T cell receptor (TCR) down-regulation is a consequence of specific receptor engagement and plays an important role in modulating the T cell response. We have investigated the role of protein kinase C (PKC) and protein tyrosine kinases (PTK) in the induction ofTCR down-regulation. We report that the mutation of S126 in the CD3-y chain that is known to inhibit phorbol-12-myristate 13acetate-induced TCR down-regulation does not affect down-regulation induced by a specific agonist. In addition, agonist-induced TCR down-regulation is not affected by blockade or depletion of PKC, neither by blockade or lack of PTK, while the same treatments efficiently interfere with T cell activation. These results demonstrate that TCR down-regulation is induced by early events which follow specific engagement by an agonist and can be dissociated from those required for full T cell activation.