Expression Of Recombinant Human Acid Fibroblast Growth Factor In Lactococcus Lactic And The Therapy For Ulcerative Colitis In Mice

Objective:construction food-grade expression vector in lactic acid bacteria, expression human acidic fibroblast growth factor in lactic acid bacteria NZ9700, make a aFGF live germ product, investigate the treatment of dextran sulfate sodium (DSS) induced ulcerative colitis in mice.Methods:construct expression vector pGMN4-USP45-LEISS-aFGF14-154 in food grade lactic acid bacteria, screen high expression of aFGF strain, The mitogenic activity on Balb/c 3T3 cell of aFGF14-154 was detected by MTT, the live bacteria divide into high, middle and low dose groups, by comparing the mouse coat color, weight, blood in stool, colon length, the diseased tissue myeloperoxidase (MPO) activity, and observed morphological changes in colon tissue to verify its therapty for mice ulcerative colitis induced by DSS.Results:successfully construct expression vector pGMN4-USP45-LEISS-aFGF14-154 in food grade lactic acid bacteria, Electrotransfect into NZ9700, induced by nisin, aFGF14-154 expression is 50μg/ml, and in concentration of 25-200ng/ml, aFGF14-154 has mitogenic activity in vitro, high-dose live germ product has good therapeutic effect for ulcerative colitis model, for example improving the general condition and colonic shortening caused by ulcers, and promote tissue repair and maintain the structural integrity of the colon and reduced MPO activity.Conclusion:construct food grade lactic acid bacteria expression system can be a good expression of aFGF, connecting USP45 signal peptide vector secretion expression aFGF14-154; connected LEISSTDCA significant increase secretion, and aFGF14-154 has mitogenic activity in vitro, hasaFGF14-154 viable lactic acid bacteria preparations on DSS-induced colitis in mice significant improvement.