The efficacy of Triladyl 50% in cryopreservation of low concentration pathogenic trypanosomes

Abstract

The efficacy of a bull cryopreservation medium Triladyl in preservation of the various pathogenic trypanosomes was evaluated against the commonly used glycerol ethylenediamine tetraacetic acid (EDT A) sahne glucose (ESG). Trypanosoma brucei rhodesiense, T. evansi, T. b, brucel and T. congolense were first propagated in Swiss White mice. At peak of parasitemia, blood was collected from the mice by cardiac puncture and I x 102 trypanosomes/ml dilution made. This dilution was then divided into 2 equal portions which were cryopreserved in either ESG 10% glycerol or Triladyl® 50%. After 1 month of cryopreservation, 2 mediated mice were intraperitoneally administered with 0.2 ml of the cryopreserved sample and then monitored for parasitemia development. Triladyl cryopreserved T ,evansi and ESG-cryopreserved T. congolense had shorter although not significant prepatent period (PPP) compared to their counterparts in the alternate medium. The peak parasitemia was significantly higher for Triladyl®-cryopreserved T evansi Trypanosomes compared to that preserved in ESG. The parasitemia pattern for T. evansi, T. b. brucei and T. congolense were characterized by 1 wave while T. b. rhodesiense had 2 waves. For T b, brucei, T. b rhodesiense and T. congolense the number of days taken to develop peak parasitemia were shortest for ESG cryopreserved trypanosomes and this was opposite for T. evansi. In conclusion, Triladyl® can be used as an alternative cry preservative medium for trypanosomes and would be the cry preservative medium of choice for T. evansi trypanosomes based on the PPP, peak parasitaemia and days to peak parasitaemia.