Article Figures & Data
Figures
- Fig. 1.
Surface expression levels of c-Kit in FDC-P1 (A), FDC(WTKit) (B), FDC(V560GKit) (C), and FDC(D816VKit) (D), detected by immunofluorescence/flow cytometry with MAb IDC3 (antihuman c-Kit), are compared with an isotype-matched control MAb (dashed line).
- Fig. 2.
Differential sensitivity of V560GKit and D816VKit to Imatinib. FDC expressing GNNK−/S+ WTKit, GNNK−/S+ V560GKit, and GNNK−/S+ D816VKit were cultured for 48 h in the presence of Imatinib (at the concentrations indicated on the X axis). Growth was assessed using a colorimetric assay for viable cell number. In A, cells were cultured in mGM-CSF. In B, WTKit were cultured in 100 ng/ml hu-SCF. V560GKit (C) and D816VKit (D) lines were cultured without added factors. Abs, absorbance.
- Fig. 3.
Imatinib induces apoptosis in FDC(WTKit) and FDC(V560GKit). FDC-P1, FDC(WTKit), FDC(V560GKit), and FDC(D816VKit) were cultured in the presence of Imatinib and factors as indicated for 24 h. Apoptotic cells were detected by staining with Annexin-V and analysis by flow cytometry.
- Fig. 4.
GNNK+/− and S+/− isoforms do not differ in sensitivity to Imatinib. FDC expressing GNNK+/S+ WTKit, GNNK+/S- WTKit, GNNK−/S+ WTKit, GNNK+/S+ D816VKit, and GNNK−/S+ D816VKit were cultured in the presence of Imatinib for 48 h. Growth was assessed using a colorimetric assay for viable cell number. In A, cells were cultured in mGM-CSF. In B, WTKit lines were cultured in 100 ng/ml hu-SCF, and D816VKit lines were cultured in the absence of added factors. Abs, absorbance.
- Fig. 5.
Effect of Imatinib on phosphorylation of c-Kit. In A, FDC(WTKit), FDC(V560GKit), and FDC(D816VKit) were incubated in the absence of serum for 2 h with the indicated concentrations of Imatinib. FDC(WTKit) were then pulsed with 100 ng/ml SCF for 2 min. Cells were lysed and immunoprecipitation and Western blot analysis was performed as described in “Materials and Methods.” kDa, molecular weight in thousands. In B and C, Kit and phosphotyrosine bands were quantitated using ImageQuant software. All of the values are relative to WTKit stimulated with SCF (Lane 2), which was assigned an arbitrary value of 1. The extent of phosphorylation is represented as phosphorylated Kit/cell number (B) and the ratio of phosphorylated Kit:total Kit for the same number of cells (C).
- Fig. 6.
Effect of Imatinib on the activation of downstream signaling pathways. FDC-P1, FDC(WTKit), FDC(V560GKit), and FDC(D816VKit) were incubated in the absence of serum for 2 h with the indicated concentrations of Imatinib. Cells were pulsed with hu-SCF for 2 min or mGM-CSF (GM) for 15 min. Cells were lysed and Western blot analysis was performed as described in “Materials and Methods.” MW, molecular weight in thousands.
Volume 1, Issue 12
