Monoclonal antibodies directed against PSA clone 28A4 (Novacastro, UK) in a concentration of 2,5μg/ml were used to detect prostate cells, and identified using a detection system based on alkaline phosphatase-antialkaline phosphatase (LSAB2 DAKO, USA) with new-fuschin as the chromogen. To permit the rapid identification of positive cells there was no counter staining with Mayer´s hematoxilin. Levisamole (DAKO, USA) was used as an inhibitor of endogenous alkaline phosphatase, with positive and negative controls. Positive samples underwent a second stage of processing, using the monoclonal antibody against P504S clone13H4 (Novocastro, UK) and a system of detection based on peroxidase (LSAB2, DAKO, USA) with Vector VIP (Vector, USA) as the chromogen. Endogenous.
