[The immune responses of the fusion protein consisted of two copies of T-cell and B-cell epitopes of food-and-mouth disease virus VP1 type O and LTB and STI enterotoxins of Escherichia coli].
A nucleotides fragment 2020VP1 related to T-cell epitope (aa21-40) and B-cell epitope (aa141-160) of VP1 of Food-and-mouth disease virus (FMDV)type O was synthesized, and the recombined expression vector r2020-LTB-2020-STI was correctly constructed, which was used to express the fusion protein consisted of two copies of aa21-40aa141-160 of FMDV VP1 and LTB and STI Enterotoxins of Escherichia coli. The fusion protein with molecular weight of about 45kD was successfully expressed in E.coli BL21(DE3) RIL at high level and confirmed by SDS-PAGE. The purified fusion protein could be specifically recognized by CTB antibody. The purified protein was then used to vaccinate guinea pigs, rabbits and Balb/c mice at 6-8 week age, and immune responses were finally observed. The fusion protein could induce proliferation of spleen T cells in vaccinated guinea pigs and elicit a high level of neutralizing antibody in rabbits. It could be concluded that the fusion protein could activate FMDV-specific cellular immune-response and humoral immune-response simultaneously. At the same time, the vaccinated mice could survive challenge of Enterotoxigenic Escherichia coli C83902, and the sera of vaccinated rabbits could neutralize the STI toxin. Moreover, the fusion protein had no STI toxicity, indicating that the fusion protein had LTB and STI immunogenicities. Therefore, it can be concluded that the fusion protein could be explored as a potentially efficient FMDV and ETEC vaccine.
Zhuang
Juan
J
Huaiyin Teachers College, Huaiyin, Jiangsu 223001, China. dajiangsky@163.com
You
Yong-Jin
YJ
Chen
Bo
B
Rao
Zhong
Z
Pan
Jie
J
D000818:Animals; D000914:Antibodies, Viral; D001427:Bacterial Toxins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D004768:Enterotoxins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D018985:Epitopes, B-Lymphocyte / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology* / Q000633:toxicity; D005260:Female; D005536:Foot-and-Mouth Disease / Q000276:immunology*; D015870:Gene Expression; D006168:Guinea Pigs; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D011897:Random Allocation; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000633:toxicity; D014611:Vaccination
D000914:Antibodies, Viral; D001427:Bacterial Toxins; D036022:Capsid Proteins; D004768:Enterotoxins; D018985:Epitopes, B-Lymphocyte; D018984:Epitopes, T-Lymphocyte; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; C442501:VP1 protein, Foot-and-mouth disease virus; C034151:heat stable toxin (E coli); C027538:heat-labile enterotoxin, E coli