霍乱毒素作为黏膜佐剂的研究进展

Advances in the study of cholera toxin as a mucosal adjuvant

霍乱毒素(cholera toxin,CT)是霍乱弧菌分泌的一种不耐热肠毒素,既是强黏膜免疫原,又具有很强的黏膜佐剂活性,是当今研究最多且最深入的黏膜免疫佐剂之一。然而,由于CT其毒性,限制了在人体的使用。很多研究致力于使CT的佐剂性与毒性分离,CT亚基的佐剂性的研究就是方向之一。困扰黏膜疫苗的一个重要问题是很多抗原的黏膜免疫原性较弱,不能刺激有效的免疫反应,这也与黏膜免疫耐受有关,以CT为佐剂能消除机体对这些共免疫原的耐受。

Cholera toxin（CT） secreted by Vibrio cholerae is a heat-labile enterotoxin and is also an exceptionally potent mucosal immunogen.CT has also been found to be a strong adjuvant for many coadministered antigens,making it one of the most intensively studied mucosal adjuvants.Although CT is a powerful mucosal adjuvant,its toxicity is likely to preclude usage in human vaccines.Many studies have sought to separate CT＇s adjuvanticity from its toxicity;one way to do so is through the adjuvanticity of its subunits.A problem hampering mucosal vaccines is the weak immunogenicity of many antigens,causing the vaccine to fail to stimulate an effective immune response.This phenomenon is related to immune tolerance,and use of CT as a mucosal adjuvant will eliminate tolerance to the co-immunogen.