Skip to main content
. 2004 Oct 1;114(7):944–952. doi: 10.1172/JCI21786

Figure 1.

Figure 1

EGF induces CEACAM1-4L phosphorylation by EGFR in intact HT29p human colon cancer cells. Serum-starved HT29p cells were treated with buffer alone (_) or with the EGFR inhibitor PD168393 (Inhi; +) for 1 hour prior to treatment with EGF (100 nM) for 0_10 minutes. Equal amounts (100 μg) of cell lysates were immunoprecipitated (IP) with α-EGFR (A) or α-C1N3 (B) prior to analysis by SDS-PAGE and immunoblotting (IB) with α-pTyr for detection of tyrosine-phosphorylated proteins (pEGFR and pCC1) and re-immunoprobing (ReIB) with α-EGFR and α-C1N3 to account for the amount of these proteins in the immunoprecipitates. For examination of the CEACAM1-4L/EGFR association, 100 μg of cell lysates were immunoprecipitated with α-EGFR and immunoblotted with α-C1N3 (C, lanes 2_4). To account for nonspecific binding of proteins to agarose, equal amounts of proteins were incubated without the addition of antibody (C, lane 1). The results obtained were consistent in at least three experiments.