[Efficacy of immune responses induced by anti-caries DNA vaccine-loaded bacterial ghost in mice].
OBJECTIVE
To develop an anti-caries DNA vaccine-loaded Salmonella typhimurium (St) ghost and enhance the efficacy of immune responses induced by anti-caries DNA vaccine via mucosal route.


METHODS
Both pREP4 and PhiX gene E expression plasmids were transformed into StJ357 and then induced with isopropyl β-D-1-thiogalactopyranoside (IPTG). The bacterial ghosts (BG) were collected after wash and loaded with anti-caries DNA vaccine pGJGLU/VAX. Mice were divided into four groups and immunized through the nasal route with pGJGLU/VAX-loaded BG (Group Ghost+pGJGLU/VAX), pVAX1-loaded BG (Group Ghost+pVAX1), pGJGLU/VAX-Bupivacaine complex (Group pGJGLU/VAX) and pVAX1-Bupivacaine complex (Group pVAX1), respectively. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the immune responses.


RESULTS
ELISA results showed that group Ghost+pGJGLU/VAX had significantly higher level of specific anti-GLU SIgA antibody [(0.367 ± 0.086) A/µg] compared with group Ghost+pVAX1 [(0.122 ± 0.077) A/µg], Group pGJGLU/VAX[(0.068 ± 0.068) A/µg] or Group pVAX1[(0.089 ± 0.089) A/µg] (P = 0.028, 0.012 or 0.030, respectively).


CONCLUSIONS
St ghost was developed successfully, which enhanced the efficacy of immune responses induced by anti-caries DNA vaccine pGJGLU/VAX via the nasal route.
The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China.
Gaoxia
G
Liu
The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China.
Mingwen
M
Fan
The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China. Email: gjhpp@hotmail.com.
Jihua
J
Guo
D000818:Animals; D000974:Antibodies, Antinuclear; D001428:Bacterial Vaccines; D003731:Dental Caries / Q000517:prevention & control*; D007071:Immunoglobulin A, Secretory; D051379:Mice; D010957:Plasmids; D012486:Salmonella typhimurium; D019444:Vaccines, DNA
D000974:Antibodies, Antinuclear; D001428:Bacterial Vaccines; D007071:Immunoglobulin A, Secretory; D019444:Vaccines, DNA