Production and preliminary evaluation of Trypanosoma evansi HSP70 for antibody detection in Equids.

The study focuses on creating and testing a new method for diagnosing trypanosomosis in equids (horse family), specifically using the heat shock protein 70 (HSP70) from the T. evansi parasite. Initial testing indicates that the proteins captured from HSP70 may be effective in identifying T. evansi infections and reveal it has potential to be further validated with more equine serum samples.

Study Background

• Trypanosomosis is a disease caused by the T. evansi parasite, which affects members of the equid family, such as horses and donkeys.
• The current diagnostic method uses soluble antigens from whole cell lysate antigen, but has issues including lack of standardized, reproducible antigens, and ethical issues due to in vivo (inside a living organism) production.
• This study is aimed at developing a more reliable diagnostic tool using in vitro (outside the organism) production, specifically by identifying and using the heat shock protein 70 (HSP70) from the T. evansi parasite.

Procedure and Main Findings

• Researches worked on the nucleotide sequence of T. evansi HSP70, which was found to be 2116 bp long and coding for 690 amino acid residues.
• Through phylogenetic analysis (study of evolutionary relationships), it was established that T. evansi HSP70 was most closely related to T. brucei brucei and T. brucei gambiense, with T. congolense HSP70 in a separate clade (branch of evolutionary tree).
• To create a diagnostic antigen, two partial HSP70 sequences, one from the N-terminal region (HSP-1) and one from the C-terminal region (HSP-2), were expressed.
• The produced recombinants were then evaluated as diagnostic antigens using serum samples from experimentally infected donkeys.
• Both recombinant proteins were successful in detecting antibodies in immunoblot tests using serum samples from infused donkeys.
• Additionally, the recombinant HSP-2 showed similar antibody responses to whole cell lysate antigens in both immunoblot and ELISA tests, displaying potential for this new diagnostic method.

Conclusion and Further Work

• Preliminary results indicate that HSP70 could be used as a reliable antigen for detecting T. evansi infections.
• However, researchers note that further validation is required on a larger set of equine serum samples to confirm the effectiveness of HSP70 for diagnostic purposes.