Wang Jie, Zhang Ying-qian, Zhong Guang-ming, Yu Ping
Department of Immunology, Basic Medical School of Central South University, Changsha 410078, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2010 Jul;30(7):1558-61.
To investigate the antigenicity of recombinant Chlamydia trachomatis (Ct) OmcBc protein and search for the new target for early diagnosis of Chlamydia infection and Chlamydia vaccine development.
The C fragment of OmcB encoding the amino acids from T270 to T553 was amplified from Chlamydia serovar D genomic DNA. The pGEX-6p-Ct OmcBc expression plasmid was constructed and transformed into E.coli XL-1blue. The expression of recombinant Ct OmcBc protein was induced by IPTG. Serum samples were collected from 120 patients with urogenital Chlamydia infection. The antiserum samples were collected from 7 New Zealand white rabbits and 5 Balb/C mice immunized subcutaneously and intraperitoneally with Ct serovar D inactivated EB, respectively, and from 9 Balb/C mice intranasally infected with Ct serovar D live EB. The anti-Chlamydia specific antibody were titrated by an immunofluorescence assay (IFA). The reactivity of the recombinant OmcBc protein with all the above antisera was detected by ELISA.
The pGEX-6p-Ct OmcBc expression plasmid was successfully constructed. DNA sequencing showed that the inserted OmcBc was about 852 bp, encoding a protein with 284 amino acids. The expression of the recombinant GST-OmcBc was induced by IPTG, producing a fusion protein with a molecular weight of about 57 kD. The titer of the specific antibodies to Chlamydia in all the antisera was high. ELISA results showed strong reactivities of the recombinant GST-OmcBc fusion protein with all the above antisera.
OmcBc protein is an immunodominant protein of Chlamydia. The recombinant GST-OmcBc with strong antigenicity may provide a basis for further study of early diagnosis of chlamydia infection and development of Chlamydia vaccine.
研究重组沙眼衣原体（Ct）OmcBc蛋白的抗原性，寻找衣原体感染早期诊断及衣原体疫苗研发的新靶点。
从沙眼衣原体D血清型基因组DNA中扩增出编码第270至553位氨基酸的OmcB的C片段。构建pGEX-6p-Ct OmcBc表达质粒并转化至大肠杆菌XL-1blue。用异丙基-β-D-硫代半乳糖苷（IPTG）诱导重组Ct OmcBc蛋白表达。收集120例泌尿生殖道衣原体感染患者的血清样本。分别从7只经皮下和腹腔注射Ct血清型D灭活原体免疫的新西兰白兔、5只经皮下和腹腔注射Ct血清型D灭活原体免疫的Balb/C小鼠以及从9只经鼻内感染Ct血清型D活原体的Balb/C小鼠中收集抗血清样本。采用免疫荧光法（IFA）检测抗衣原体特异性抗体滴度。用酶联免疫吸附测定（ELISA）检测重组OmcBc蛋白与上述所有抗血清的反应性。
成功构建了pGEX-6p-Ct OmcBc表达质粒。DNA测序显示插入的OmcBc约852 bp，编码一个含284个氨基酸的蛋白质。IPTG诱导重组GST-OmcBc表达，并产生一个分子量约为57 kD的融合蛋白。所有抗血清中抗衣原体特异性抗体滴度均较高。ELISA结果显示重组GST-OmcBc融合蛋白与上述所有抗血清均有强反应性。
OmcBc蛋白是衣原体的免疫显性蛋白。具有强抗原性的重组GST-OmcBc可为进一步研究衣原体感染早期诊断及衣原体疫苗研发提供依据。
