[Changes of spleen cytokines in mice immunized with recombinant Bb-Eg95-EgA31 vaccine against Echinococcus
Bi-ying Zhou1, Ya-tang Chen, Wen-gui Li
1Institute of Infectious and Parasitic Diseases, the First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China.
Objective:
To investigate the level of cytokines in spleen from mice immunized with recombinant Bifidobacteria bifidum(Bb)-Eg95-EgA31 vaccine of Echinococcus granulosus (Eg) and challenged with Eg protoscoleces.
Methods:
56 female BALB/c mice were randomly divided into 7 groups: Recombinant Bb-Eg9S-95-EgA31 vaccine subcutaneous injection (group A), intramuscular injection (B), intranasal immunization (C), oral administration (D), blank vector control (E), Bb control (F) and MRS control (G). Mice in all groups were challenged with 50 Eg protoscoleces on the 8th week after vaccination and sacrificed on the 25th week after infection. Spleens were collected to prepare splenocytes, which were cultured under activation of crude Eg antigen (EgAg), with concanavalin A (ConA) or lipopolysaccharide (LPS) stimulation and non-stimulation as control. The splenocyte supernatants were collected to determine the levels of interferon-gamma (IFN-gamma), interleukin-12 (IL-12), tumour necrosis factor-alpha (TNF-alpha) and IL-10 by ELISA.
Results:
The level of IFN-gamma in groups A [(137.5 +/- 23.2) pg/ml], B [(162.5 +/- 23.2) pg/ml], C [(250.0 +/- 53.5) pg/ml] and D [(215.0 +/- 37.4) pg/ml] was higher than that of group G [(50.0 +/- 10.7) pg/ml] (P < 0.01). The level of IL-12 in groups A [(27.5 +/- 4.6) pg/ml], B [(32.5 +/- 4.6) pg/ml], C [(45.0 +/- 5.4) pg/ml] and D [(35.0 +/- 5.4) pg/ml] was higher than that of group G [(15.0 +/- 5.4) pg/ml] (P < 0.01). The level of TNF-alpha in groups A [(275.0 +/- 46.3) pg/ml], B [(325.0 +/- 46.3) pg/ml], C [(450.0 +/- 53.5) pg/ml] and D [(350.0 +/- 53.5) pg/ml] was higher than that of group G [(150.0 +/- 53.5) pg/ml] (P < 0.01). The level of IL-10 in groups A [(37.5 +/- 4.6) pg/ml], B [(35.0 +/- 5.4) pg/ml], C [(25.0 +/- 5.4) pg/ml] and D [(32.5 +/- 4.6) pg/ml] was lower than that of group G [(45.0 +/- 5.4) pg/ml] (P < 0.05 or P < 0.01).
Conclusion:
The recombinant Bb-Eg95-EgA31 vaccine can induce a protective Th1 type immune response in mice
