Objective: To evaluate the potential adjuvant effect of Agrocybe aegerita lectin(AAL), which was isolated from mushroom, against a virulent H_9N_2 strain in vivo and in vitro. Methods: In trial 1, 50 BALB/c male mice(...Objective: To evaluate the potential adjuvant effect of Agrocybe aegerita lectin(AAL), which was isolated from mushroom, against a virulent H_9N_2 strain in vivo and in vitro. Methods: In trial 1, 50 BALB/c male mice(8 weeks old) were divided into five groups(n=10 each group) which received a subcutaneous injection of inactivated H_9N_2(control), inactivated H_9N_2+0.2%(w/w) alum, inactivated H_9N_2+0.5 mg recombinant AAL/kg body weight(BW), inactivated H_9N_2+1.0 mg AAL/kg BW, and inactivated H_9N_2+2.5 mg AAL/kg BW, respectively, four times at 7-d intervals. In trial 2, 30 BALB/c male mice(8 weeks old) were divided into three groups(n=10 each group) which received a subcutaneous injection of inactivated H_9N_2(control), inactivated H_9N_2+2.5 mg recombinant wild-type AAL(AAL-wt)/kg BW, and inactivated H_9N_2+2.5 mg carbohydrate recognition domain(CRD) mutant AAL(AAL-mut R63H)/kg BW, respectively, four times at 7-d intervals. Seven days after the final immunization, serum samples were collected from each group for analysis. Hemagglutination assay, immunogold electron microscope, lectin blotting, and coimmunoprecipitation were used to study the interaction between AAL and H_9N_2 in vitro. Results: Ig G, Ig G1, and Ig G2 a antibody levels were significantly increased in the sera of mice co-immunized with inactivated H_9N_2 and AAL when compared to mice immunized with inactivated H_9N_2 alone. No significant increase of the Ig G antibody level was detected in the sera of the mice co-immunized with inactivated H_9N_2 and AAL-mut R63 H. Moreover, AAL-wt, but not mutant AAL-mut R63 H, adhered to the surface of H_9N_2 virus. The interaction between AAL and the H_9N_2 virus was further demonstrated to be associated with the CRD of AAL binding to the surface glycosylated proteins, hemagglutinin and neuraminidase. Conclusions: Our findings indicated that AAL could be a safe and effective adjuvant capable of boosting humoral immunity against H_9N_2 viruses in mice through its interaction with the viral surface glycosylated proteins, hemagglutinin and neuraminidase.展开更多
基金supported by the National Natural Science Foundation of China(Nos.30771501 and 81102850)the National Basic Research Program(973)of China(No.2011CB811302)+2 种基金the National Mega Project on Major Drug Development(No.2009ZX09301-014-1)the Chinese 111 Project(No.B06018)the Wuhan Municipal Project(No.201160923296),China
文摘Objective: To evaluate the potential adjuvant effect of Agrocybe aegerita lectin(AAL), which was isolated from mushroom, against a virulent H_9N_2 strain in vivo and in vitro. Methods: In trial 1, 50 BALB/c male mice(8 weeks old) were divided into five groups(n=10 each group) which received a subcutaneous injection of inactivated H_9N_2(control), inactivated H_9N_2+0.2%(w/w) alum, inactivated H_9N_2+0.5 mg recombinant AAL/kg body weight(BW), inactivated H_9N_2+1.0 mg AAL/kg BW, and inactivated H_9N_2+2.5 mg AAL/kg BW, respectively, four times at 7-d intervals. In trial 2, 30 BALB/c male mice(8 weeks old) were divided into three groups(n=10 each group) which received a subcutaneous injection of inactivated H_9N_2(control), inactivated H_9N_2+2.5 mg recombinant wild-type AAL(AAL-wt)/kg BW, and inactivated H_9N_2+2.5 mg carbohydrate recognition domain(CRD) mutant AAL(AAL-mut R63H)/kg BW, respectively, four times at 7-d intervals. Seven days after the final immunization, serum samples were collected from each group for analysis. Hemagglutination assay, immunogold electron microscope, lectin blotting, and coimmunoprecipitation were used to study the interaction between AAL and H_9N_2 in vitro. Results: Ig G, Ig G1, and Ig G2 a antibody levels were significantly increased in the sera of mice co-immunized with inactivated H_9N_2 and AAL when compared to mice immunized with inactivated H_9N_2 alone. No significant increase of the Ig G antibody level was detected in the sera of the mice co-immunized with inactivated H_9N_2 and AAL-mut R63 H. Moreover, AAL-wt, but not mutant AAL-mut R63 H, adhered to the surface of H_9N_2 virus. The interaction between AAL and the H_9N_2 virus was further demonstrated to be associated with the CRD of AAL binding to the surface glycosylated proteins, hemagglutinin and neuraminidase. Conclusions: Our findings indicated that AAL could be a safe and effective adjuvant capable of boosting humoral immunity against H_9N_2 viruses in mice through its interaction with the viral surface glycosylated proteins, hemagglutinin and neuraminidase.