Adjuvant effects mediated by the carbohydrate recognition domain ofAgrocybe aegerita lectin interacting with avian influenza H9N2 viral surface glycosylated proteins

杨树菇血凝素糖识别域与禽流感病毒H_9N_2表面糖蛋白结合介导的佐剂效果（英文）

Objective： To evaluate the potential adjuvant effect of Agrocybe aegerita lectin （AAL）, which was isolatedfrom mushroom, against a virulent H9N2 strain in vivo and in vitro. Methods： In trial 1, 50 BALB/c male mice （8 weeksold） were divided into five groups （n=10 each group） which received a subcutaneous injection of inactivated HgN2（control）, inactivated HgN2＋0.2% （w/w） alum, inactivated HgN2＋0.5 mg recombinant AAL/kg body weight （BW）, inac-tivated HgN2＋1.0 mg AAl_/kg BW, and inactivated H9N2＋2.5 mg AAL/kg BW, respectively, four times at 7-d intervals. Intrial 2, 30 BALB/c male mice （8 weeks old） were divided into three groups （n=10 each group） which received a sub-cutaneous injection of inactivated HgN2 （control）, inactivated HmN2＋2.5 mg recombinant wild-type AAL （AAL-wt）/kg BWand inactivated H9N2＋2.5 mg carbohydrate recognition domain （CRD） mutant AAL （AAL-mutR63H）/kg BW,respectively, four times at 7-d intervals. Seven days after the final immunization, serum samples were collectedfrom each group for analysis. Hemagglutination assay, immunogold electron microscope, lectin blotting, and co-immunoprecipitation were used to study the interaction between hAL and HgN2 in vitro. Results： IgG, IgG1, and IgG2aantibody levels were significantly increased in the sera of mice co-immunized with inactivated HgN2 and AAL whencompared to mice immunized with inactivated H^N2 alone. No significant increase of the IgG antibody level was de-tected in the sera of the mice co-immunized with inactivated HgN2 and AAL-mutR63H. Moreover, AAL-wt, but notmutant AAL-mutR63H, adhered to the surface of H9N2 virus. The interaction between AAL and the H9N2 virus wasfurther demonstrated to be associated with the CRD of AAL binding to the surface glycosylated proteins, hemagglutininand neuraminidase. Conclusions： Our findings indicated that AAL could be a safe and effective adjuvant capable ofboosting humoral immunity against HgN2 viruses in mice through its interaction with the viral surface glycosylatedproteins, hemagglutinin and neuraminidase.

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.