The effect of Echinococcus hydatid cyst fluid and protoscoleces on mouse peritoneal macrophages and spleen lymphocytes

The toxic effect of protoscoleces and secondary hydatid cysts fluid of Echi nococcus multilocularis and Echinococcus granulosus was studied on mouse C5 7BL/ 6J peritoneal macrophages (PM) and spleen lymphocytes (Sly). Direct ex posure of isolated E. granulosus protoscoleces and hydatid cyst fluid with PM led to the lysis of target cells after 7 and 12 hours, respectively. A 1 2-hour exposition off. multilocularis protoscoleces with PM caused an 80 % reduction in viability of the cells. The cytotoxic activity of the E. multi locularis tissue was not observed. The cultures of PM were incubated in the presence of the E. multilocularis and E, granulosus hydatid cysts for 18, 36 hours or 7 days. The level of viabili- ty of PM was closely connected wi th the time of exposition and the lowest viability of PM was observed after 7 days of cultivation. Medium in which E, multiocularis had been cultured had cytotoxic activity. No toxicity was detected with media in which E. gr granulosus cysts had been cultured for 18, 36 hours or 7 days. The same int eraction of hydatid cyst cultured medium with mouse SLy was not dependent o n the time of incubation. The medium of E.granulosus hydatid cysts displaye d a lower viability after 12 hours of incubation (ranging from 0 to 28 %) a s compared with E. multilocularis (37 to 42 %).