Antigens expressed in feline enteroepithelial-stages parasites of Toxoplasma gondii.

In an investigation aimed to identify Toxoplasma gondii antigens expressed in feline enteroepithelial-stages parasites, a cDNA library was constructed and fourteen positive clones were isolated by immunoscreening using sera from cats immunized with feline enteroepithelial-stages parasites. By DNA sequence homology analysis, these fourteen isolated clones were classified into four groups: hypoxanthine-guanine phosphoribosyl transferase (HGPRT) cDNA, heat shock protein 70 (HSP70) cDNA, 14-3-3 protein homologue cDNA, and cDNA encoding an unknown product. In an indirect immunofluorescence antibody test, sera from mice immunized with the recombinant protein encoded by the cDNA for HGPRT, HSP70, 14-3-3 protein, or the unknown product each showed a relatively high level of immunoreactivity with feline enteroepithelial-stages parasites.