[Immunity of native SpaA and recombinant SpaA-N against Erysipelothrix rhusiopathiae infection in mice].
OBJECTIVE
We evaluated the effects of surface protective antigen A (SpaA) and its N-teminal protective domain (rSpaA-N) against Erysipelothrix rhusiopathiae infection in mice.


METHODS
The SpaA was purified by electroelution from NaOH-extracted antigen of Erysipelothrix rhusiopathiae strain C43311. The rSpaA-N was expressed in E. coli BL21 as a soluble protein by IPTG inducing, and purified with GST affinity chromatography. Mice of each group were subcutaneously immunized three times with 50 microg or 100 microg of native SpaA, rSpaA-N or NaOH-extracted antigen with in complete or incomplete Freund adjuvant at 2-week intervals. Five mice of each group were challenged with 100 LD50 of Erysipelothrix rhusiopathiae virulent strain C43065 two weeks after the third immunization, and the specific antibody responses for SpaA was determined by indirect ELISA.


RESULTS
Mice immunized with 50 microg or 100 microg of native SpaA, rSpaA-N, or NaOH-extracted antigen were protected completely against the challenge with strain C43065. There was no significant difference (P < 0.05) between the antibody responses observed for native SpaA, rSpaA-N and NaOH-extracted antigen at any dosages. Western blot results indicated that the native SpaA and rSpaA-N were recognized specifically by an antiserum against the native SpaA of strain C43311.


CONCLUSIONS
These results demonstrated that the rSpaA-N is a protective antigen of Erysipelothrix rhusiopathiae serotype 2 strains, and might be a useful vaccine candidate against swine erysipelas.
Nazierbieke
Wulumuhan
W
College of Biology and Environmental Sciences, Jishou University, Jishou 416000, China. ulum@jsu.edu.cn
Zhang
Lei
L
He
Cui
C
Peng
Qingzhong
Q
Borrathybay
Entomack
E
D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D004888:Erysipelothrix / Q000276:immunology* / Q000502:physiology; D004889:Erysipelothrix Infections / Q000276:immunology*; D005260:Female; D051379:Mice; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology* / Q000378:metabolism
D000942:Antigens, Bacterial; D000954:Antigens, Surface; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D011994:Recombinant Proteins; C114457:SpaA protein, Erysipelothrix rhusiopathiae