A 2.9 kDa Fasciola hepatica-recombinant protein based ELISA test for the detection of current-ovine fasciolosis trickle infected

Vet Parasitol. 2006 Apr 15;137(1-2):67-73. doi: 10.1016/j.vetpar.2005.12.015. Epub 2006 Jan 18.

Abstract

The suitability of an enzyme linked immunosorbent assay (ELISA) test with a 2.9 kDa Fasciola hepatica-recombinant protein (FhrAPS) for diagnosing early and current-ovine fasciolosis was analyzed, and compared to that obtained by using a direct ELISA for detecting F. hepatica-circulating FhES antigens and to the coprological sedimentation for fluke egg quantitation. Fourteen Gallega autochthonous breed sheep were experimentally infected with metacercariae by a trickle system (small repetitive infections) and divided into two groups: G-I represented a primary infection for 34 weeks; G-R, animals with primary infection and reinfected 18 w.a.p.i. Seven sheep were left uninfected as the control group (G-C). Serum IgG antibody values against the FhrAPS rose rapidly by 1st w.a.p.i. in all infected sheep. Antibody levels in those with primary infection (G-I, G-C) peaked at 10 weeks, diminishing slightly and levelling from 16 to 34 weeks. Those with primary infection reinfected at 18 weeks had a rebound effect with the highest values observed. Circulating F. hepatica-ES antigens were detected by the 1st w.a.p.i. in all infected groups peaking at 6 weeks, decreasing rapidly to uninfected control values by 10 weeks of infection. Faecal egg-output started 11 weeks after primary infection. An increase in the IgG antibody as well as antigen responses to the FhrAPS and to anti-FhES from the 18 w.a.p.i. was recorded in G-T and G-R after the challenge infection. Antibody levels remained high whereas antigenemia values diminished after 6 weeks. A positive significant correlation between the IgG response against the FhrAPS and the F. hepatica circulating antigens (r2 = 0.428, p = 0.001) was obtained. In conclusion, our standardized diagnostic ELISA for fasciolosis based on the detection of IgG responses to the FhrAPS would be a valuable tool to diagnosis early and current F. hepatica-infections in sheep.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antigens, Helminth / blood
  • Enzyme-Linked Immunosorbent Assay / methods
  • Enzyme-Linked Immunosorbent Assay / veterinary*
  • Fasciola hepatica / immunology*
  • Fascioliasis / diagnosis
  • Fascioliasis / parasitology
  • Fascioliasis / veterinary*
  • Feces / parasitology
  • Helminth Proteins / immunology*
  • Parasite Egg Count / veterinary
  • Random Allocation
  • Recombinant Proteins / immunology
  • Sensitivity and Specificity
  • Sheep
  • Sheep Diseases / diagnosis*
  • Sheep Diseases / parasitology
  • Time Factors

Substances

  • Antigens, Helminth
  • Helminth Proteins
  • Recombinant Proteins