Destructive effect of gamma irradiation on Echinococcus granulosus metacestodes

Current options for treatment of cystic echinococcosis (CE), including chemotherapeutics and surgical approaches, are not satisfactory in certain cases of resistant cysts in vulnerable or inaccessible organs. Therefore, potential means of therapy are needed. The present work evaluated the effect of gamma irradiation on mestacestode causing CE. Metacestode of Echinococcus granulosus were exposed to 15, 30, and 60 Gy irradiation and examined after 24 h for viability, morphologic, and ultrastuctural alterations by light and electron microscopy. Apoptosis was determined by caspase-3 activity by colorimetric assay and immunohistochemistry. The irradiated metacestodes showed loss of viability, damage of protoscolices, formation of lipid droplets and vacuoles, and separation of the germinal layer. Apoptosis was prominent after irradiation. Our results suggested that gamma irradiation have therapeutic potential in CE. Moreover, understanding the destructive effect of irradiation may help in developing prophylactic measures against CE. Further studies are needed to test the efficacy of ionizing radiation in long-term animal models.