Caspase expression in primary alligator pulmonary fibroblasts. Nuclei were stained with 4′,6′-diamidino-2-phenylindole hydrochloride (blue) and a-tubulin (green) was immunolabeled with mAb DM1A. (a) Caspase 3 (red) immunolabeled with polyclonal antibody 9662; (b) Caspase 7 (red) immunolabeled with polyclonal antibody 9492; (c) Caspase 9 (red) immunolabeled with polyclonal antibody 9502; (d) Western blots of M. alligatoris-infected (I) and control (U) fibroblast lysates probed with primary antibodies against uncleaved poly(ADP-ribose) polymerase (PARP; 9542) and caspases 3, 7, and 9. Alkaline phosphatase-conjugated secondary antibodies were detected with 5-bromo-4-chloro-3-indolyl phosphate p-toluidine salt plus nitroblue tetrazolium. Blots were digitized by using an AlphaImager (Alpha Innotech, San Leandro, CA). Contrast was normalized for better clarity by using the Auto Contrast feature after cropping and alignment with Adobe Photoshop CS 8.0 (Adobe Systems, San Jose, CA). Filled arrowheads indicate bands consistent with the predicted sizes of uncleaved and cleaved mammalian caspases and PARP. Unfilled arrowheads indicate absence of predicted bands.