Proteomic analysis of Taenia hydatigena cyst fluid reveals unique internal microenvironment

•A total of 520 proteins were identified in T. hydatigena CF, 430 of which were of sheep origin.•Proteins associated with amino acid synthesis and complement cascades were abundant in the CF.•Glutamate metabolism and anti-oxidative reactions were identified as important events in the CF.•T. hydatigena metacestodes may have a special internal growth microenvironment.

Taenia hydatigena is a parasitic flatworm that is widely distributed around the world. Using MS/MS, the proteome of T. hydatigena cyst fluid (CF) was profiled and a total of 520 proteins were identified, 430 of which were of sheep origin. T. hydatigena shared 37 parasite-origin and 109 host-origin CF proteins with Echinococcus granulosus. Compared with E. granulosus, T. hydatigena had much more CF proteins associated with amino acid synthesis and complement cascades. In addition, glutamate metabolism and anti-oxidative reactions were identified as relatively more important events. These results suggest that T. hydatigena metacestodes have internal microenvironment with special immune and oxidative conditions.