Short report: Echinococcus granulosus from Xinjiang, PR China: cDNAS encoding the EG95 vaccine antigen are expressed in different life cycle stages and are conserved in the oncosphere.
The EG95-based vaccine protects sheep from infection with the dog tapeworm Echinococcus granulosus. The EG95 encoding gene is a member of a multigene family, several members of which are expressed in the oncosphere, believed to be the target of immunity induced by the vaccine. E. granulosus exhibits extensive intraspecific (strain) variation, and variability of the eg95 gene in different isolates of E. granulosus may directly impact the effectiveness of the EG95-based vaccine. We analyzed the eg95 gene from E. granulosus collected in Xinjiang, in northwest China, where hydatid disease is hyperendemic. The gene is expressed in oncospheres, protoscoleces, and immature and mature adult worms, and the eg95 gene family was shown to comprise two basic sequence types. Very limited sequence variation was evident in the EG95 protein from oncospheres. This high degree of sequence conservation predicts that the vaccine will continue to be effective in China and elsewhere.
Zhang
Wenbao
W
Molecular Parasitology Laboratory, Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research and University of Queensland, Brisbane, Queensland, Australia.
Li
Jun
J
You
Hong
H
Zhang
Zhuangzhi
Z
Turson
Gulinul
G
Loukas
Alex
A
McManus
Donald P
DP
D000595:Amino Acid Sequence; D000818:Animals; D000947:Antigens, Helminth / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D002681:China; D018076:DNA, Complementary / Q000096:biosynthesis / Q000737:chemistry; D004285:Dogs; D004443:Echinococcosis / Q000469:parasitology / Q000517:prevention & control / Q000662:veterinary; D004446:Echinococcus / Q000235:genetics* / Q000254:growth & development / Q000276:immunology; D005786:Gene Expression Regulation; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D008018:Life Cycle Stages / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D018510:RNA, Helminth / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D012756:Sheep; D012757:Sheep Diseases / Q000469:parasitology / Q000517:prevention & control; D014612:Vaccines / Q000737:chemistry / Q000235:genetics / Q000276:immunology
D000947:Antigens, Helminth; D018076:DNA, Complementary; C446034:EG95 protein, Echinococcus granulosus; D015801:Helminth Proteins; D018510:RNA, Helminth; D014612:Vaccines