Transfection of rabbit articular chondrocytes by the calcium phosphate procedure: Improvement of efficiency and reproducibility.

The understanding of cartilage disorders relies on the possibility of studying mechanisms which monitor the regulation of matrix protein genes through introducing efficiently and in a reproducible manner these genes, or their regulatory regions, into cells. To this end, we attempted to improve the transfection efficiency of rabbit articular chondrocytes by the calcium phosphate procedure. Transfection efficiencies were assessed by measuring the expression of the Lac Z reporter gene encoding β-galactosidase using anin situ staining (X-gal staining) and an enzymatic assay (β-galactosidase assay).Results revealed that addition of 4 U ml(-1) of hyaluronidase before and during transfection increases by 2 to 4-fold the transfection efficiency of rabbit articular chondrocytes. Furthermore, we demonstrated that the use of a "giant" calcium phosphate DNA coprecipitate gives a higher transfection efficiency and much more reproducible results than those obtained with classical small volumes of precipitates.