STUDIES ON THE DETECTION OF CIRCULATING ANTIGENS IN THE EARLY STAGE OR THE NONPULMONARY TYPE OF PARAGONIMASIS WESTERMANI BY USING MONOCLONAL ANTIBODIES AGAINST PwMJ-SAg / 中国血吸虫病防治杂志

The result regarding the application of McAbs against PwMJ-SAg in the detection of the circulating antigens(CAg) in sera from the patients (early stage and nonpulmonary type) with paragonimiasis westermani was reported in this paper. CAg in the sera from 35 patients in the early stage and 15 nonpulmonary type of patients was 100% positive by using McAb IB1 and JB4 out of 8 McAbs against PwMJ-SAg. Furthermore, these two McAbs didnot react crossly with the sera from 25 normal subjects, 15 patients with clonorchiasis, 15 patients with fasciolopsiasis, 15 patients with schistosomiasis japonica, 16 patients with Brugian filariasis or 10 patients with pulmonary tuberculosis. However, they crossly reacted with 8 samples of sera from 15 patients (53.3%) with pagumogonimiasis skrjabini. The McAb IB1 and IB4, threfore, are appropriate as the reagents to diagnose paragonimiasis westermani (early stage or nonpulmonary type). Moreover, they are also valuable, to a certain degree, to diagnose pagumogonimiasis skrjabini.The projet was supported by NNSFC Department of parasitology .Anhni Medical University, Hefei

Cloning and Identification of an Unknown Gene Encoding 10.6 kDa Protein of Schistosoma japonicum / 中国寄生虫学与寄生虫病杂志

Objective To screen a new schistosome vaccine candidate. \ Methods\ Schistosoma japonicum adult cDNA library was screened using sera from immune rabbits vaccinated with irradiated cercariae and monoclonal antibodies against membrane antigen of S.japonicum schistosomula. Three different fragments of S.japonicum cDNA genes were cloned into pGEM-T vector. The sequences of the inserts were determined using an automatic DNA sequencer and were analysed using Blast program. One of the unknown genes (B8) was selected and its ORF sequence (291 bp) was subcloned into eukaryotic expression vector. The recombinant plasmids were identified by restrictive enzymes and PCR amplification. The positive recombinant plasmids (pBK/SjB8) were transformed into host bacteria XL1-blue, and were then induced by IPTG for expression. SDS-PAGE and Western blotting analysis of total cellular protein from the bacteria were performed to detect the gene products. Results The results demonstrated that ORF of SjB8 gene was subcloned into the plasmid pBK-CMV and could express as fusion protein in XL1-blue. The results of SDS-PAGE and Western-blot also showed that the molecular weight of the fusion protein with 3 kDa ?-galactosidase was approximately 13^6 kDa and the actual molecular weights of the SjB8 was 10^6 kDa. The expressed fusion product of pBK/Sj-B8 could be recognized by immune serum and McAb. Conclusion A new gene of S.japonicum vaccine candidate (SjB8) was cloned into eukaryotic expression vector pBK-CMV and could express 10^6 kDa schistosome protein. The results provide foundation for further study of the protein for its posibility as candidate vaccine.