Transient inhibition of cellular tyrosine phosphorylation by STI571 in STI571-resistant Ba/F3.p210 cells.

(A) STI571-resistant Ba/F3.p210 cells treated with 1 μmol/L STI571 for 2 to 48 hours, following a 2-hour STI571 deprivation. Immunoblotting of the lysates from these cells was performed with anti-pTyr (upper left-hand panel), anti-ABL (middle left-hand panel), and anti-SHP2 as a control for loading (lower left-hand panel). (B) STI571-resistant Ba/F3.p210 cells treated with 1 μmol/L STI571 for 2 to 48 hours, with no STI571 deprivation prior to treatments. Immunoblotting of the lysates from these cells was performed as in (A).