I am trying to detect senescent cells in OA cartilage. For this I have tried SA b gal staining but the results are not good with very little staining . Since enzyme activity is very tricky to detect and fixation and freeze thawing has adverse effect, I am stuck with the experiment. I am not sure whether doing immunostaining with b gal antibody would make any difference. Fluorescence substrates may be another option as well. persons with first hand experience with these please give your opinion. Thanks