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 t
Li-bao MABao-yang XUMin HUANGLv-hui SUNQing YANGYi-jie CHENYa-lin YINQi-gai HEHui SUN
