Escherichia coli Nissle 1917 as safe vehicles for intestinal immune targeted therapy—A review

Abstract:

Abstract:It is difficult to stimulate efficient gut mucosal immune response to intestinal infection．This article critically reviews the research progressin Escherichia coli strain Nissle1917 (EcN) actingas a safe vehicle for the intestinal mucosal immunity，to restore gastrointestinal disorder and relieve ulcerative colitis． EcN is an orally administered probiotics，combining the excellent colonization and non-immunogenic character，and can be an ideal live vector candidate．This strain could be a tumor-targeted delivery of TAT-Apoptin fusion gene to colorectal cancer．In the treatment of ulcerative colitis and Crohn's disease，the recombinant strain of EcN can be used as a target therapeutics for defensins presenting．Genetically modified EcN could be an ideal carrier organism for gut-focused in situ synthesis and expression of specific localized antigen delivery into the intestine，and stimulate specific mucosal immune response． In vitro trial demonstrated that intestinal recombinant E． coli Nissle-HA110-120 has the potential to stimulate antigen specific response，but EcN itself does not induce mucosal immune response and influence peripheral tolerance to self-antigen． At the same time，there are evidences that EcN is safe．Recombinant E．coli Nissle-HA110-120 does not migrate，clonally expand and activate specific CD4 + T cells，neither in healthy mice nor in other animals with acute colitis，even when the intestinal epithelium suffer from inflammation and the barrier function of the epithelial layer being destroyed．