A TsA-12 clone encoding a 53 kDa glycoprotein was identified by
immunoscreening of a Trichinella spiralis ML cDNA expression library.
The 53 kDa glycoprotein of T. spiralis is expressed in the postcapsule
larvae (15-day-old ML) and adult worms but not in the precaspule
(35-day-old ML) or NBL. The glycoprotein showed high sequence similarities
(90.7% and 89.5%, respectively) to the Trichinella britovi and
Trichinella native 53 kDa proteins (encapsulated species); however,
they showed low sequence similarities (66.6% and 68.8%, respectively)
to the Trichinella pseudospiralis and Trichinella papuae 53 kDa proteins
(non-encapsulated species) [27]. The 53-KDa glycoprotein of T. spiralis
contains species-specific epitopes. The antibody response induced by
the 53 kDa glycoprotein ismainly due to protein epitopes, and the antibody
response against glycan epitopes is less important [34]. Western
blot analysis with the different Trichinella species 53 kDa recombinant
proteins indicated that the 53-kDa antigens induced an early and
species-specific antibody response in mice that were infected with
Trichinella