A simple cost-effective method for purification of <i>Clostridium chauvoei</i> cell-surface proteins for detection of antibodies against blackleg disease vaccine.

Cell-surface proteins of <i>Clostridium chauvoei</i> were purified using a simple method. Bacterial cultures were centrifuged and agitated vigorously in phosphate buffered saline with or without further glycine treatment and ammonium sulfate precipitation. Rabbits were immunized subcutaneously with a blackleg disease vaccine twice with a two-week interval. Immunized sera were collected one week after the second injection. Enzyme-linked immunosorbent assay (ELISA) was performed using the proteins purified by the second method as the coating antigen. Bradford assay results showed a higher protein concentration in the second than the first method. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis analysis showed multiple bands for the cell-surface proteins of <i>C. chauvoei</i> in the first method and a sharp band equivalent to flagellin protein in the second method. The ELISA results indicated that the purified proteins were capable of detecting antibodies against Blackleg disease vaccine. The purified protein would be an alternative antigen for indirect ELISA in order to monitor the immune response in vaccinated farm animals.