Comparison of survival time of Echinococcus granulosus protoscolices in different culture media and temperatures and evaluation of their ability to generate cysts in mice.

Abstract

Hydatidosis is a disease caused by the larval stage of Echinococcus granulosus, which has great importance in medicine and veterinary medicine. Protoscolices (PSCs) of fertile hydatid cysts play a critical role in secondary echinococcosis after surgery. Fertile cysts were acquired from infected sheep at the local municipal abattoir in Ahvaz, southwest of Iran. PSCs were obtained aseptically and transferred to 10 different culture media and kept at 4°C and 37°C to determine the duration of PSCs’ survival. Then, 2000 live PSCs from each of the culture media were injected into the peritoneal cavity of BALB/c mice. After five months, the mice were evaluated in terms of cyst number, size, and weight. The highest PSCs survival time at 4°C was related to RPMI-1640 medium and cyst fluid for 50 and 45 days, respectively. Also, at 37°C, the longest survival time of PSCs was related to cyst fluid and RPMI-1640 media for 30 and 29 days, respectively. The highest level of infection and median cyst number was observed in mice received PSCs from the RPMI-1640 medium at 4°C, and the highest level of infection in mice at 37°C was related to the DMEM low glucose (L) medium. The current study indicated that 4°C was a more suitable temperature for in vitro storage of live PSCs. The maximum amount of infection was observed in mice received PSCs from the RPMI-1640 medium at 4°C. The present study is the first attempt to compare the ability of PSCs to generate hydatid cysts in mice after being cultured in different media and at various temperatures.