Fig. 4
The expression level and localization of CD13 of eight different human glioblastoma cell lines. (A) Quantitative analysis of CD13 mRNA expression using qRT-PCR (n = 3, independent cell preparations). (B) An example of western blot detecting intracellular (130 kDa) and surface (160 kDa) CD13 expression (n = 2, independent cell preparations). GAPDH (37 kDa) was used as control. Full length blots are presented in Additional file 7. (C-F) Flow cytometric analyses of total (C,D) and surface (E,F) expression of CD13. Representative histograms show total (C) and surface (E) expression of CD13. Quantitative analysis of the percentage of cells expressing CD13 in total (D) or on surface (F) (n = 4, independent cell preparations). (G,H) Immunofluorescence staining of glioblastoma cell lines: CD13 (red), F-actin (phalloidin, green) and nuclei (DAPI, blue). Confocal image of U1242 cell showing the dot-like distribution of CD13. Scale bar, 30 μm (G). Immunofluorescence images of eight different cell lines. Scale bars, 400 μm (H)