Comparative analysis of excretory-secretory antigens of Trichinella spiralis and Trichinella britovi muscle larvae by two-dimensional difference gel electrophoresis and immunoblotting

According to 2-D DIGE analysis, a total of twenty-two proteins including potentially immunogenic proteins and proteins produced only by one of the two Trichinella species were subjected to LC-MS/MS for protein identification. From these proteins seventeen could be identified, of which many were identified in multiple spots, suggesting that they have undergone post-translational modification, possibly involving glycosylation and/or proteolysis. These proteins included 5'-nucleotidase, serine-type protease/proteinase, and p43 glycoprotein (gp43) as well as 49 kDa E-S protein (p49). Our findings also suggest that some of the commonly identified proteins were post-translationally modified to different extents, which in certain cases seemed to result in species-specific modification. Both commonly and specifically recognized immunoreactive proteins were identified by 2-DE immunoblotting; shared antigens were identified as gp43 and different protease variants, whereas those specific to T. britovi included multiple isoforms of the 5'-nucleotidase.Both 2-D DIGE and 2-DE immunoblotting approaches indicate that T. spiralis and T. britovi produce somewhat distinctive antigen profiles, which contain E-S antigens with potential as species-specific diagnostic markers for Trichinella. Our results also demonstrate the value of 2-D DIGE as a versatile tool to compare secretomes of different Trichinella species for pinpointing factors contributing to the interaction with the host.Trichinellosis is a food-borne parasitic zoonosis caused by nematodes of the genus Trichinella. Twelve genotypes of Trichinella have been identified worldwide [1-3], four of which are confirmed to exist in Europe: T. spiralis, T. nativa, T. britovi and T. pseudospiralis. In Poland, during various epidemiological surveys, only two Trichinella species have been identified in domestic and wild animals, T. spiralis and T. britovi [4,5]. T. spiralis is the etiological agent of most human infections and deaths cau