Screening of high antigenic fragments of Marburg virus GP protein and their immunogenicity / 军事医学

ABSTRACT

Objective To screen small fragments with high antigenicity in order to overcome the defects of the full-length Marburg virus GP as a vaccine antigen.Methods Based on the structure and function of GP sequence [amino acids(aa) 1-681], three small fragments,including GP1△(aa 25-239), GPM(aa 250-520) and GP2△(aa 436-648), were expressed by prokaryotic cells and immunized into mice, and the serum specific antibodies were detected after different immunization time.The proliferation of spleen lymphocytes and the concentration of cytokines of immunized mice were also measured.Results ELISA test results showed that high humoral immunity of GP2△ was produced as the full-length GP group did, and was higher than that of GP1△ and GPM (P<0.05).GP2△ immunization groups exhibited a higher SI value in mouse splenic lymphocytes stimulated by ConA than the mixed GP immunization groups did(P<0.05), but the effect was the opposite when mouse splenic lymphocytes were stimulated by the mixed GP.In addition, the amount of cytokines IL-2 and IFN-γ of mouse splenic lymphocytes in the GP2△ group was larger than that of the saline group (P<0.05), but smaller than that of the mixed GP group.Conclusion The fragment GP2△ can induce not only the high humoral immunity as GP does,but also moderate cellular immunity, which can be used for vaccine design.