I have been trying to isolate the sertoli cells from rat testes but have not been able to get enough sertoli cells. To separate the Sertoli and germ cells, I used a mix of enzymes that contained 0.1% collagenase, 0.2% hyaluronidase [H6254; Sigma], 0.04% Dnase I [D5024; Sigma], and 0.03% trypsin inhibitor in PBS. But at the end, I could not get enough Sertoli cells. The purity was really low. Can I use different concentrations of percoll and use them on the top of the final cell pellet, then redisperse the cells and spin them to isolate the pure sertoli cells.