| The Wiskott Aldrich syndrome protein acts downstream of CD 2 and the CD2AP and PSTPIP 1 adaptors to promote formation of the immunological synapse . ^^^ Here , we show that antigen induced formation of T cell : APC conjugates and synapses is abrogated in WASp deficient T cells and that CD 2 engagement evokes interactions between the proline rich region required for WASp translocation to the synapse and the PSTPIP 1 adaptor SH 3 domain and between the PSTPIp 1 coiled coil domain and both CD 2 and another CD 2 binding adaptor , CD2AP . ^^^ These data , together with the impairment in CD 2 induced actin polymerization observed in WASp deficient cells , suggest that PSTPIP 1 acts downstream of CD2 / CD2AP to link CD 2 engagement to the WASp evoked actin polymerization required for synapse formation and T cell activation . . ^^^ |