Calcium Phosphate-Mediated Transfection of Adherent Cells or Cells Growing in Suspension: Variations on the Basic Method.

This protocol describes two variations of the calcium phosphate-mediated transfection method. The first can be used with all types of adherent cells, but is particularly useful for polarized epithelial cells, which do not efficiently take up material by endocytosis through the apical plasma membrane. To improve transfection efficiency, adherent cells are trypsinized and collected by centrifugation. The cells are resuspended in the calcium phosphate-DNA coprecipitate and then plated again on tissue culture dishes. Most lines of cells grown in suspension are resistant to calcium phosphate-mediated transfection methods; however, a few cell lines grown as suspension cultures (e.g., HeLa cells) can be transfected using the second modified calcium phosphate procedure described here.