Heterologous protection in pigs induced by a plasmid-cured and crp gene-deleted Salmonella choleraesuis live vaccine.
In this study, we exploited a crp (cAMP receptor protein) gene-deleted, virulence plasmid-cured Salmonella choleraesuis mutant with decreased carbon source utilization, designated S.C.-Deltacrp/vpl(-), as a live vaccine strain. Normal weight gain with no clinical signs was observed in pigs immunized with high doses of S.C.-Deltacrp/vpl(-) live vaccine. Vaccination in pregnant sows induced high maternal antibodies, which could prevent piglets from Salmonella infection. Moreover, serial transmission of the vaccine strain in piglets produced no evidence of reversion to virulence. Furthermore, the peripheral blood mononuclear cells from immunized piglets also developed Salmonella specific T-cell proliferative response in vitro. Our results indicate that immunogenic antigens in S.C.-Deltacrp/vpl(-) can induce adequate immunity to protect pigs against challenge with a heterologous virulent strain. Thus, this mutant holds promise for the development of a new live S. choleraesuis vaccine.
Chu
Chun-Yen
CY
Graduate Institute of Animal Vaccine Technology, National Pingtung University of Science and Technology, 1 Shuehfu Road, Neipu, Pingtung 91201, Taiwan. cychu@mail.npust.edu.tw
Wang
Shiang-Yiu
SY
Chen
Zeng-Weng
ZW
Chien
Maw-Sheng
MS
Huang
Ji-Ping
JP
Chen
Jen-Jin
JJ
Hong
Li-Shian
LS
Shiau
Ai-Li
AL
Tsai
Jeng-Liang
JL
Wu
Chao-Liang
CL
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D049109:Cell Proliferation; D002373:Cyclic AMP Receptor Protein / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D007112:Immunity, Maternally-Acquired; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000235:genetics; D011247:Pregnancy; D012475:Salmonella / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000503:physiopathology / Q000517:prevention & control*; D022562:Salmonella Vaccines / Q000235:genetics / Q000276:immunology*; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000503:physiopathology / Q000517:prevention & control*; D013601:T-Lymphocytes / Q000276:immunology; D014613:Vaccines, Attenuated / Q000235:genetics / Q000276:immunology; D014774:Virulence