Fig. 4. The inability of A431 cell to attach to CSPE substratum is due to lack of annexin 6 expression. (A) The ability of various human cultured cell lines, IMR90, MG63, MRC5, WI38 and A431 cells to attach to CSPE substratum was examined using the cell attachment assay as described in the Materials and Methods. The results are expressed as the means and ranges of determinations from at least three experiments. (B) 50 µg of protein from cell lysates were analysed by western blotting of annexin 6 and annexin 4 with mouse monoclonal antibodies to human annexin 6 and human annexin 4, respectively.