Biochemical characterization and differential expression of a 16.5-kilodalton tegument-associated antigen from the liver fluke Fasciola hepatica.

Kimberly Cabán-Hernández's picture
TitleBiochemical characterization and differential expression of a 16.5-kilodalton tegument-associated antigen from the liver fluke Fasciola hepatica.
Publication TypeJournal Article
Year of Publication2012
AuthorsGaudier, JF, Cabán-Hernández, K, Osuna, A, Espino, AM
JournalClin Vaccine Immunol
Volume19
Issue3
Pagination325-33
Date Published2012 Mar
ISSN1556-679X
KeywordsAnimals, Antibodies, Helminth, Antigens, Helminth, Chromatography, Affinity, Disease Models, Animal, Escherichia coli, Fasciola hepatica, Fascioliasis, Gene Expression Regulation, Gene Library, Humans, Immunohistochemistry, Molecular Weight, Rabbits, Recombinant Proteins
Abstract

A cDNA encoding a 16.5-kDa protein termed FhTP16.5 was identified by immunoscreening of a cDNA library from Fasciola hepatica adult flukes using pooled sera from rabbits infected with F. hepatica for 4 weeks. Quantitative reverse transcriptase PCR (qPCR) analysis revealed that FhTP16.5 is not expressed in unembryonated eggs. It is poorly expressed in miracidia and highly expressed at the juvenile and adult stages; however, significant differences were found between the expression levels of FhTP16.5 in juveniles versus adult flukes. Recombinant FhTP16.5 was expressed at high levels in Escherichia coli, purified by affinity chromatography, and used to raise anti-FhTP16.5 polyclonal antibodies in rabbits. Immunoblot analysis using the anti-FhTP16.5 IgG antibody identified FhTP16.5 in crude and tegumental extracts and in excretory-secretory products of F. hepatica. The protein was not detected in crude extracts of Schistosoma mansoni or Schistosoma japonicum. Antibodies to FhTP16.5 were detected in the sera of rabbits at 3 to 12 weeks of F. hepatica infection as well as in the sera of humans with chronic fascioliasis; these findings suggest that FhTP16.5 could be a good antigen for serodiagnosis of fascioliasis. Immunohistochemistry demonstrated that FhTP16.5 localizes to the surface of the tegument of various developmental stages and in parenchymal tissues of the adult fluke. Such specific localization makes FhTP16.5 an attractive target for immunoprophylaxis or chemotherapy.

DOI10.1128/CVI.05501-11
Alternate JournalClin. Vaccine Immunol.
PubMed ID22278327
PubMed Central IDPMC3294618
Grant List1SC1AI096108-01A2 / AI / NIAID NIH HHS / United States
3-U54-RR022762-03S1 / RR / NCRR NIH HHS / United States
R25GM061838 / GM / NIGMS NIH HHS / United States
SC1 AI096108 / AI / NIAID NIH HHS / United States
U54 RR022762 / RR / NCRR NIH HHS / United States