Identification of Lyn.

CLL samples were incubated with anti-IgM or control antibody for 2 minutes. Samples were either immunoblotted for tyrosine phosphorylation (top panels), or immunoprecipitated (IP) with rabbit anti-Lyn antibody and immunoblotted for tyrosine phosphorylation (middle panels), or immunoprecipitated with rabbit isotype control antibody and immunoblotted for tyrosine phosphorylation (bottom panels). Proteins were separated on a 4% to 15% gradient SDS-PAGE gel. The molecular mass of protein standards is shown.