IMMUNOHISTOCHEMICAL DETECTION OF CD31 ANTIGEN IN NORMAL AND NEOPLASTIC CANINE ENDOTHELIAL-CELLS

This report describes the immunohistochemical detection of von Willebr and's factor (vWf) and CD31 antigen in paraffin wax-embedded, formalin -fixed tissue sections of canine normal organs and vascular neoplasms. CD31 antigen and vWf were detected in endothelial cells of all organs examined, except for the endothelia of the renal glomeruli, which wer e negative for vWf. All haemangiomas examined (15) were positive for b oth markers. Eleven of 15 haemangiosarcomas were positive for vWf and all 15 expressed the CD31 antigen. All other neoplasms investigated (f ibrosarcomas, schwannomas, haemangiopericytomas) were negative for bot h markers. It is concluded that immunohistochemical detection of CD31 antigen is of value for studying vascular disorders of the dog in rout inely processed tissue.