Coexpression of CD34 and CD43 on KG1a cells and stimulation with MoAbs to CD34 or CD43. (A) FACS analysis of KG1a cells stained with anti-CD34 (4A1) or anti-CD43 (MEM59). Solid lines represent staining with specific antibodies, and dotted lines represent staining with the secondary reagent alone. (B) Western blots of Triton X-100 lysates from KG1a cells, probed with anti-CD34 (4A1, lane 1) or anti-CD43 (MEM59, lane 2). (C) Western blots of equal amounts of Triton X-100 lysates from KG1a cells stimulated with anti-CD34 (4A1, lanes 2 through 7), anti-CD43 (MEM59, lanes 9 through 14) for the indicated times or incubated with MOPC21 (control IgG, lanes 1 and 8) for 30 minutes at 37°C, probed with anti-pTyr (4G10). Molecular size markers are indicated on the left (kD).