Molecular cloning and characterization of an antigenic protein with a repeating region from Clonorchis sinensis.
In the course of immunoscreening of Clonorchis sinensis cDNA library, a cDNA CsRP12 containing a tandem repeat was isolated. The cDNA CsRP12 encodes two putative peptides of open reading frames (ORFs) 1 and 2 (CsRP12-1 and -2). The repetitive region is composed of 15 repeats of 10 amino acids. Of the two putative peptides, CsRP12-1 was proline-rich and found to have homologues in several organisms. Recombinant proteins of the putative peptides were bacterially produced and purified by an affinity chromatography. Recombinant CsRP12-1 protein was recognized by sera of clonorchiasis patients and experimental rabbits, but recombinant CsRP12-2 was not. One of the putative peptide, CsRP12-1, is designated CsPRA, proline-rich antigen of C. sinensis. Both the C-termini of CsRP12-1 and -2 were bacterially produced and analysed to show no antigenicity. Recombinant CsPRA protein showed high sensitivity and specificity. In experimental rabbits, IgG antibodies to CsPRA was produced between 4 and 8 weeks after the infection and decreased thereafter over one year. These results indicate that CsPRA is equivalent to a natural protein and a useful antigenic protein for serodiagnosis of human clonorchiasis.
Kim
T Y
TY
Department of Parasitology, Chung-Ang University Faculty of Medicine, Seoul 156-756, Korea.
Kang
S Y
SY
Ahn
I Y
IY
Cho
S Y
SY
Hong
S J
SJ
D000595:Amino Acid Sequence; D000818:Animals; D000947:Antigens, Helminth / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D003004:Clonorchis sinensis / Q000235:genetics / Q000276:immunology*; D018509:DNA, Helminth; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D011817:Rabbits; D011994:Recombinant Proteins; D012091:Repetitive Sequences, Nucleic Acid
D000947:Antigens, Helminth; D018509:DNA, Helminth; D011994:Recombinant Proteins