Production and Characterization of Cry5B Spore Crystal Lysate for In Vivo Studies

HD1 Cry5B spore crystal lysate (SCL) and HD1 spore lysate (SL) for in vivo studies were produced and the concentration of Cry5B protein in HD1-Cry5B SCL was determined as previously described [37 (link)]. Tribendimidine was kindly provided by Dr. Shu-Hua Xiao at the Chinese Centers for Disease Control and Prevention. Pyrantel pamoate was purchased from Sigma (Cat# P6210-5G). On the day of use, SL and Cry5B SCL aliquots, tribendimidine powder and Pyrantel pamoate powder were resuspended in distilled water right before in vivo treatment. Cry5B SCL suspension was kept on ice until gavage. When combinations were used, the drugs were given together in a single oral gavage. SL was used as the control for the Cry5B dose-response experiment, but water was used as the control for other experiments. Repeated studies in our lab have shown that SL alone has no effect on parasite burden of fecal egg counts relative to water (manuscript in preparation). Purified Cry5B for cyathostomin developmental inhibition assays was produced as described before [30 (link),38 (link)] and dissolved in 20 mM HEPES (pH8.0) right before setting up the assays.