Inmunodiagnóstico de fasciolosis humana y ovina empleando una fracción de 24-29 kDa de Fasciola hepatica obtenida mediante inmunoadsorción

Abstract

In order to identify specific and sensitive polypeptides for human and sheep immunodiagnosis of fasciolosis, the protein components of E-S products of adult F.hepatica were separated by gel filtration chromatography (Sephacryl S-300) followed by SDS-PAGE to identify a 24 - 29 kDa fraction. With this fraction a rabbit immune antiserum was prepared and then coupled to a sepharose column matrix to develop an affinity chromatography which permitted the direct immunoadsortion of these polypeptides from crude E-S extracts. The affinity adsorved proteins were then assessed as antigen, using serum samples from 12 human patients and 20 sheep with fasciolosis as well as serum samples from 31 human patients and 20 non infected sheep, as controls, by Western blot analysis. The adsorved antigenic fraction in positive human samples exhibited a sensitivity value of 91.6 % and a specificity value of 100%. The sensitivity values were 93.3% and 80% for chronic and prepatent sheep infection, respectively. On the other hand, none of the control human or sheep negative sera reacted against this fraction, demonstrating 100% specificity values. Therefore, it may be concluded that immunoadsortion of F. hepatica 24-29 kDa fractions from crude E-S extracts is an efficient procedure of obtaining antigens for accurate serodiagnosis of F. hepatica infection in human and animal species.