戊二醛聚合方法对血红蛋白聚合产物免疫学特性的影响

发布时间：2018-04-18 16:28

本文选题：戊二醛聚合方法 + 血红蛋白聚合产物　；参考：《西北大学》2009年硕士论文

【摘要】： 血红蛋白类氧载体(Hemoglobin-based oxygen carriers,HBOCs)是一类通过血红蛋白分子表面化学修饰或分子间交联而形成分子量较大的血红蛋白制品,原料血红蛋白主要来源于人、猪、牛,常用戊二醛作为交联剂,具有无病原微生物污染、制剂组成相对简单、可长期体外保存、使用时不需要交叉配型等优点。但此类制剂也存在潜在的问题,即异源蛋白和蛋白质修饰/聚合反应可能使得此类产品刺激或抑制机体免疫系统功能,从而影响机体体液免疫和细胞免疫,对机体产生免疫毒性作用。免疫原性是免疫毒性评价的重要组成部分,目前已成为研究重点。本文主要采用抗体生成反应方法,初步研究了戊二醛聚合反应前后猪、牛血红蛋白的免疫原性所发生的变化,以研究聚合反应对此两类蛋白免疫原性的影响。实验结果显示,首先猪、牛血红蛋白刺激机体生成抗体的作用都很弱,但经过戊二醛聚合后体液免疫刺激作用明显增强;其次,抗牛血红蛋白抗体不识别聚合牛血红蛋白,抗分子内聚合牛血红蛋白抗体也不识别天然牛血红蛋白,而分子间聚合牛血红蛋白抗体却可以识别天然的牛血红蛋白;最后,抗猪血红蛋白抗体可识别聚合猪血红蛋白,抗聚合猪血红蛋白抗体也可识别天然猪血红蛋白。可见,猪、牛血红蛋白免疫原性很低,但是戊二醛聚合反应改变了蛋白质的结构,使其免疫刺激作用显著增强,提高了猪、牛血红蛋白刺激机体生成抗体的能力。另外,不同蛋白质空间结构的改变对免疫原性产生影响的机理可能不同。戊二醛分子内聚合反应可能没有改变猪血红蛋白抗原决定簇的结构,但却改变了牛血红蛋白抗原决定簇的结构,而分子间聚合对牛血红蛋白抗原决定簇没有影响。戊二醛聚合反应可造成此两类蛋白免疫学性质发生不同改变的事实说明,虽然不同种血红蛋白的氨基酸序列具有很高的相似性,但聚合反应所产生的免疫学特性的影响可能完全不同。这种影响与聚合反应所修饰的蛋白质的部位及其相邻空间结构的特点有密切关系。同种化学修饰方法制备的不同来源血红蛋白的聚合产物可具有不同的免疫学刺激特性,而不同种化学修饰方法制备的相同来源血红蛋白产物也具有不同的免疫学特性。因此,必须分别研究不同种HBOCs产品的免疫学特性,不能仅根据某一HBOCs产品分子的免疫学特性推断用相同制备方法获得的不同来源的血红蛋白产品或用不同制备方法获得的相同来源的血红蛋白产品的免疫学特征。
[Abstract]:Hemoglobin-based oxygen carriers (HBOCs) is a kind of hemoglobin products with high molecular weight, which is formed by chemical modification or intermolecular crosslinking of hemoglobin molecules. The raw materials of hemoglobin-based hemoglobin are mainly from human, pig and cow.The common glutaraldehyde as crosslinking agent has the advantages of no contamination of pathogenic microorganisms, relatively simple composition, long-term preservation in vitro and no cross-matching when used.But there are also potential problems with such preparations, that is, heterologous proteins and protein modification / polymerization may cause such products to stimulate or inhibit the immune system of the body, thereby affecting the humoral and cellular immunity of the body.Immune toxicity to the body.Immunogenicity is an important part of immunotoxicity evaluation, and has become the focus of research.In this paper, the immunogenicity of porcine and bovine hemoglobin before and after glutaraldehyde polymerization was studied by antibody forming reaction, and the effect of polymerization on the immunogenicity of these two proteins was studied.The results showed that, first of all, pig and bovine hemoglobin stimulated the body to produce antibody very weak, but after glutaraldehyde polymerization, the humoral immune stimulation effect was obviously enhanced; secondly, the anti-bovine hemoglobin antibody did not recognize polymerized bovine hemoglobin.Anti-intramolecular polymerized bovine hemoglobin antibodies also do not recognize natural bovine hemoglobin, whereas intermolecular polymerized bovine hemoglobin antibodies can recognize natural bovine hemoglobin; finally, anti-porcine hemoglobin antibodies can recognize polymerized porcine hemoglobin.Anti-polymeric porcine hemoglobin antibodies can also recognize natural porcine hemoglobin.It can be seen that the immunogenicity of pig and bovine hemoglobin is very low, but glutaraldehyde polymerization has changed the structure of protein, enhanced its immunostimulatory effect, and improved the ability of pig and bovine hemoglobin to stimulate the body to produce antibody.In addition, the effects of different protein spatial structure on immunogenicity may be different.The intramolecular polymerization of glutaraldehyde may not change the structure of porcine hemoglobin antigen determinant, but it changes the structure of bovine hemoglobin antigen determinant, while intermolecular polymerization has no effect on bovine hemoglobin antigen determinant.The fact that glutaraldehyde polymerization can result in different immunological properties of these two proteins suggests that although the amino acid sequences of different hemoglobin are highly similar,But the effects of polymerization on immunological properties may be completely different.This effect is closely related to the site of the modified protein and the characteristics of its adjacent spatial structure.The polymerized products from different sources of hemoglobin prepared by the same chemical modification method may have different immunological stimulation properties, and the same source hemoglobin products prepared by different chemical modification methods also have different immunological characteristics.Therefore, it is necessary to study the immunological characteristics of different HBOCs products,The immunological characteristics of hemoglobin from different sources obtained by the same preparation method or from the same source by different preparation methods should not be inferred from the immunological properties of a certain HBOCs product molecule.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2009
【分类号】：R392

【引证文献】