Protection of chickens from fowl cholera by vaccination with recombinant adhesive protein of Pasteurella multocida.

The recombinant adhesive protein (rCp39) of Pasteurella multocida strain P-1059 (serovar A:3) was prepared and purified with a hybrid condition of affinity chromatography. The rCp39 was highly protective for chickens from fowl cholera by challenge-exposure with parental strain P-1059 or heterologous strain X-73 (serovar A:1) compared to various kind of vaccines. Sixteen groups of ten chickens each were subcutaneously inoculated twice with 100, 200 or 400 microg proteins of rCp39, native Cp39, native outer membrane protein H (OmpH) or recombinant OmpH, or 100 microg proteins of crude capsular extract (CCE) of strains P-1059 or X-73 at 2 weeks interval. Five chickens of each group were challenge-exposed with each strain 2 weeks after the second inoculation. As the results, 60-100% protections were demonstrated in the chickens against both strains. Fisher's exact test indicated no significant differences (P<0.05) in vaccine types and dosages. ELISA and Western blot analysis indicated that the chicken anti-rCp39 sera reacted to whole-cell lysate of parental or heterologous strains. In conclusion, rCp39 is a cross-protective recombinant adhesive antigen of P. multocida capsular serogroup A strains. Moreover, a hybrid condition of affinity chromatography was successfully demonstrated and protected the immunogenicity of recombinant protein.