Comparative study of three novel ion exchange resins with DEAE-cellulose for the purification of Trypanosoma evansi.

Ion exchange chromatography is a method that uses the different surface charges of trypanosomes and blood cells to separate them. This makes it possible to use molecular and immunological methods to diagnose or study these protozoans. DEAE-cellulose resin is commonly used to perform this method. The goal of this study was to compare three novel chromatographic resins designated as PURIFICA™ (Y-C2N®, Y-HONOH®, and Y-CNC3®). The resins were evaluated based on their ability to isolate the parasite, purification time, examination of parasite viability and morphology, and trypanosome recovery potential after passing through the columns. In terms of the evaluated parameters, there was no significant difference between DEAE-cellulose and the three tested resins in most experiments. However, PURIFICA™ (Y-C2N®, Y-HONOH®, and Y-CNC3®) resins are less expensive and easier to prepare than DEAE-Cellulose, making them an alternative for the purification of Trypanosoma evansi.

First record of Trypanosoma evansi DNA in Dichelacera alcicornis and Dichelacera januarii (Diptera: Tabanidae) flies in South America.

BACKGROUND: Trypanosoma evansi infects a large number of wild and domestic animals and causes a spoliative disease known as surra. It is mechanically transmitted, mainly by biting flies of the genera Tabanus and Stomoxys. The detection of T. evansi DNA in the feeding apparatus of Dichelacera alcicornis and Dichelacera januarii from South America is reported, to the best of our knowledge, for the first time. METHODS: Tabanids were collected weekly from February 2018 to February 2019 from two sites. The feeding apparatus was removed and DNA extraction, polymerase chain reaction and sequencing were performed. RESULTS: A 205-base pair fragment of the variant surface protein RoTat 1.2 gene, confirmed by DNA sequencing, was amplified from the feeding apparatus of D. alcicornis and D. januarii. CONCLUSIONS: This is, to the best of our knowledge, the first record of T. evansi DNA in South American tabanids.