Molecular characterization of the Taenia solium Tso31 antigen and homologous of other Taenia species from Peru

Abstract

Several studies have been performed to determine specific antigens for the diagnosis of tapeworms. One of these antigens is Tso31, which is used to differentiate Taenia solium and Taenia saginata in human feces. The aim of the present work was the molecular characterization of this protein in different tapeworm specimens collected in Peru, T. omisa (n = 6), T. hydatigena (n = 7), T. taeniaeformis (n = 4), T. pisiformes (n = 1), T. multiceps (n=7) and T. solium (n = 10). Total DNA was extracted from each proglottid using a commercial DNA kit for tissue. A nested-PCR was used to amplify a fragment of the previously described oncosphere-specific protein Tso31 gene. The PCR products were analyzed by 1.5% agarose gel electrophoresis and visualized after ethidium bromide staining. All PCR-positive products were sequenced and their sequences were compared. Of all the tapeworms analyzed only T. solium and T. multiceps amplified the Tso31 gene. All sequences were identical for each specie. Our T. solium Tso31 showed 100% of similarity when compared with published GenBank sequences. The difference between T. solium and T. multiceps Tso31 samples was 8.1%. In conclusion, our results show that the tsol31 gene is not exclusive to T. solium.

Primers application with the Tso31 gene target in the molecular identification of Taenia solium

“…Tso31 gene is one of the most promising antigens to differentiate T.solium from T saginata. Since this gene is presented in T.solium but not in T.saginata, it was recommended for differential diagnosis (14).…”

Nested PCR for the detection of Taenia solium DNA in stool samples

“…The results showed the amplification of a single 234-bp fragment only in the samples with T. solium DNA. However, Vargas-Calla et al (2019) evaluated whether the Tso31 gene was conserved in other Taenia species and found that PCR of it was negative in DNA from T. omisa, T. hydatigena, T. pisiformis , and T. taeniaeformis but was positive in T. multiceps ; the authors suggested that the Tso31 gene sequence is not exclusive to T. solium (13). Considering the above, it is important to continue evaluating the possible cross-reactions of this test with other, related parasites.…”