Lucius R, Kern A, Seeber F, Pogonka T, Willenbücher J, Taylor H R, Pinder M, Ghalib H W, Schulz-Key H, Soboslay P
Institute for Tropical Hygiene, University of Heidelberg, FRG.
Trop Med Parasitol. 1992 Sep;43(3):139-45.
The full length cDNA of the immunodominant Ov33 protein of Onchocerca volvulus was expressed in E. coli using various vector constructs. Expression was best with the vectors pGEX2T and pCG808fx, yielding fusion protein Ov33-GST and Ov33-MBP, respectively. Purified fusion protein Ov33-GST and O. volvulus antigen extracts (OvAg) were used to compare antibody responses (IgM and IgG-subclasses) of patients infected with O. volvulus, Brugia malayi, Wuchereria bancrofti, Mansonella perstans/Loa loa and of Sudanese control sera. Sera of all groups contained IgM reacting with Ov33-GST and with OvAg. There was no IgG1 response to Ov33-GST. IgG1 responses to OvAg were only detected in filariasis sera. IgG2 and IgG3 responses were not detectable or marginal in all groups. The IgG4 reaction of onchocerciasis patients to Ov33-GST and to OvAg was high, whereas few other filariasis sera contained IgG4 antibodies to Ov33-GST and to OvAg. A serodiagnostic test for onchocerciasis based on detection of IgG4 to Ov33-GST had a sensitivity of 93.3% and a specificity of 96%. An epitope common to Ov33 and to the homologous proteins of other filarial species was demonstrated with a monoclonal antibody. Purified Ov33-MBP fusion protein was used to follow the development of the antibody response of four chimpanzees experimentally infected with O. volvulus. The data indicates that antibodies to Ov33 are induced by developing worms and later parasite stages.
盘尾丝虫免疫显性Ov33蛋白的全长cDNA通过各种载体构建体在大肠杆菌中表达。使用载体pGEX2T和pCG808fx时表达效果最佳，分别产生融合蛋白Ov33-GST和Ov33-MBP。纯化的融合蛋白Ov33-GST和盘尾丝虫抗原提取物（OvAg）用于比较感染盘尾丝虫、马来布鲁线虫、班氏吴策线虫、常现曼森线虫/罗阿丝虫的患者以及苏丹对照血清的抗体反应（IgM和IgG亚类）。所有组的血清中均含有与Ov33-GST和OvAg反应的IgM。对Ov33-GST没有IgG1反应。仅在丝虫病血清中检测到对OvAg的IgG1反应。所有组中均未检测到或仅检测到少量的IgG2和IgG3反应。盘尾丝虫病患者对Ov33-GST和OvAg的IgG4反应较高，而其他丝虫病血清中很少含有针对Ov33-GST和OvAg的IgG4抗体。基于检测针对Ov33-GST的IgG4的盘尾丝虫病血清学诊断试验的敏感性为93.3%，特异性为96%。用单克隆抗体证明了Ov33与其他丝虫物种同源蛋白共有的一个表位。纯化的Ov33-MBP融合蛋白用于追踪四只经实验感染盘尾丝虫的黑猩猩抗体反应的发展情况。数据表明，针对Ov33的抗体是由发育中的蠕虫和后期寄生虫阶段诱导产生的。
