模拟胃酸条件下的幽门螺杆菌CAT特异性抗体活性研究

Immune protection of specific antibody to Helicobacter pylori catalase under a mimic gastric condition in vitro

幽门螺杆菌是常见的感染性病原菌,人类多种疾病发生与此菌感染有关。预防和治疗菌体感染及引发的相关疾病仍是现代医学面临的课题。实验利用原核表达的幽门螺杆菌过氧化氢酶(1~380 aa)免疫家兔,获得效价为1∶6 000的特异性抗血清,经硫酸铵沉淀法得到初步纯化的抗体。在体外模拟胃酸环境下(pH3.4)将抗体进行水解。SDS-PAGE结果显示,抗体的重链能被水解。水解后的抗体产物经ELISA方法检测,仍然具有与抗原特异性结合的能力。实验结论证实,在体外环境下特异性幽门螺杆菌抗体保护作用不会被胃蛋白酶的水解而破坏,提示口服特异性抗体预防和治疗幽门螺杆菌感染可能是一条可行的途径。

Helicobacter pylori is a common pathogen which leads to many human infectious diseases.It is a dilemmatic issue in current clinic medical sciences to prevent Hp infection and cure related diseases resulted from this pathogenic infection.In this paper,Hp catalase(1-380aa) expressed in procaryotic cells was used to immunize rabbit and antiserum titer was detected using ELISA.The raw immunoglobulin G was isolated and purified with sulfate ammonium sedimentation,and then antibody hydrolysis and the specific reaction were tested by SDS-PAGE and ELISA.The results showed that antibody heavy chains could be hydrolyzed by pepsin in a acidic solution at pH3.4 but the hydrolyzed antibody could keep the ability of specific reaction with fusion catalase.The following conclusion can be deduced that antibody immune protection can not be destroyed in an acidic gastric environment and it is a potential and feasible policy to cure and prevent its infection with specific neutral antibody against Helicobacter pylori.