Opisthorchis viverrini: identification of a glycine-tyrosine rich eggshell protein and its potential as a diagnostic tool for human opisthorchiasis.
A cDNA encoding a novel eggshell protein (OvESP) with high-glycine (49.2%) and -tyrosine (27.8%) content was cloned from the human liver fluke Opisthorchis viverrini. In the adult parasite, the RNA products of the OvESP gene are limited to the vitelline follicles. They have a size of 800 nucleotides and are already present in 2-week-old juveniles. Immune sera of hamsters, experimentally infected, and humans, naturally infected with O. viverrini, detect bacterially expressed recombinant OvESP (rOvESP). A rabbit anti-rOvESP antiserum only reacts with the shells of intrauterine eggs in tissue sections of the parasite. Comparison of rOvESP with the parasite's excretion/secretion products as diagnostic tools for human opisthorchiasis shows a higher sensitivity (0.82-0.48) and specificity (0.97-0.91) of the recombinant protein in the ELISA technique. But the observed weak cross-reactivity of immune sera from mice infected with Schistosoma mansoni, Schistosoma mekongi, and Fasciola gigantica in Western blots of rOvESP indicates that the diagnostic quality of this protein might be compromised if infections by other trematodes are present.
Ruangsittichai
Jiraporn
J
Department of Biology, Faculty of Science, Mahidol University, Bangkok, Thailand.
Viyanant
Vithoon
V
Vichasri-Grams
Suksiri
S
Sobhon
Prasert
P
Tesana
Smarn
S
Upatham
Edward Suchart
ES
Hofmann
Annemarie
A
Korge
Günter
G
Grams
Rudi
R
D000595:Amino Acid Sequence; D000818:Animals; D000947:Antigens, Helminth / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics; D018509:DNA, Helminth / Q000235:genetics; D004527:Egg Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005399:Fishes / Q000469:parasitology; D015723:Gene Library; D005998:Glycine / Q000032:analysis; D015801:Helminth Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009889:Opisthorchiasis / Q000175:diagnosis*; D009891:Opisthorchis / Q000235:genetics / Q000276:immunology*; D011817:Rabbits; D017422:Sequence Analysis, DNA / Q000379:methods; D014443:Tyrosine / Q000032:analysis
D000947:Antigens, Helminth; D018076:DNA, Complementary; D018509:DNA, Helminth; D004527:Egg Proteins; D015801:Helminth Proteins; C015753:chorion proteins; D014443:Tyrosine; D005998:Glycine