Effect of Csk on CXCL12-induced chemotaxis.

Csk inhibits CXCL12-induced chemotaxis. JCaM1.6 cells were transiently transfected with empty vector (■), Lck wt (■), or the constitutively active Lck Tyr505Phe construct (▨). All 3 constructs were also cotransfected with a vector encoding Csk, as indicated in the Figure. (A) The different transfectants were subjected to chemotaxis assay toward CXCL12 (25 ng/mL). Mean ± SD of 2 experiments (12 filters). *P < .01 as compared with cells transfected with Lck wt alone. (B) Lysates from transfected JCaM1.6 cells were immunoblotted with either an anti-Lck antibody or an anti-HA antibody to detect Csk.