Figure 1.
Tyrosine phosphorylation of Vav1 after antibody-induced engagement of LFA-1 in NK cells. LFA-1 on NK cells was cross-linked with anti-CD11a and a F(ab′)2 goat anti–mouse antibody for the indicated times at 37°C. (A) Cell lysates were resolved by 4–20% SDS-PAGE and immunoblotted with biotinylated anti phosphotyrosine Ab, PY-20 (p-Tyr, left). (B) Vav1 was immunoprecipitated from cell lysates, separated on 6% SDS-PAGE, and blotted with PY-20 mAb (p-Tyr, left). The same blots were reprobed with an anti-Vav1 Ab (Vav1, right).