[Immunoreactivity of the recombinant protein of Echinococcus granulosus antigen B].
OBJECTIVE
To express the recombinant antigen B (rAgB) of Echinococcus granulosus (Eg) and investigate its immunoreactivity.


METHODS
The rAgB gene fragments were inserted into pET41a (+) prokaryotic vector. The recombinant plasmid was transformed into E. coli BL21 (DE3) and followed by expression of the protein induced by isopropyl beta-D-1-thiogalactopyranoside (IPTG). The protein was purified with sepharose 4B by affinity chromatography, and tested by SDS-PAGE electrophoresis. Its immunoreactivity was examined by Western blotting, and a rapid diagnosis kit for human echinococcosis was used as control.


RESULTS
The constructed recombinant plasmid pET41a-rAgB was identified by PCR, digestion with restriction enzyme and sequencing. The recombinant rAgB-GST was about Mr 40 800 with a purity of 78.4%. Western blotting showed that the positive rate of rAgB-GST reacting with sera of cystic echinococcosis (CE), alveolar echinococcosis (AE), paragonimiasis westermani and clonorchiasis sinensis patients, and healthy persons is 79.2%(95/120), 51.1% (23/45), 0 (0/32), 0 (0/20), and 0 (0/24), respectively. Its overall sensitivity and specificity were 79.2% (95/120) and 81.0% (98/121), respectively, slightly higher than the sensitivity (72.8%, 75/103) and specificity (76.9%, 30/39) of the rapid diagnosis kit for human echinococcosis.


CONCLUSIONS
The rAgB-GST recombinant protein is recognized by the sera of CE and AE patients, showing a proper immunoreactivity.
Medical Research Center, First Teaching Hospital of Xinjiang Medical University, Urumqi 830054, China.
Guo-Dong
GD
Lv
Tao
T
Liu
Ren-Yong
RY
Lin
Xing
X
Wang
Jun-Hua
JH
Wang
Zhi-Hui
ZH
Ren
Hao
H
Wen
Xiao-Mei
XM
Lu
D000818:Animals; D004443:Echinococcosis / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D048209:Echinococcus granulosus / Q000276:immunology*; D005822:Genetic Vectors; D006801:Humans; D008074:Lipoproteins / Q000097:blood / Q000276:immunology*; D010957:Plasmids; D011994:Recombinant Proteins / Q000276:immunology
D008074:Lipoproteins; D011994:Recombinant Proteins; C514022:antigen B, Echinococcus granulosus