A novel cDNA clone encoding a specific excretory/secretory antigen of larval Trichinella pseudospiralis

Abstract

A cDNA library for Trichinella pseudospiralis was constructed to study the expression of speci®c antigens. Four positive clones were identi®ed using antibodies against the excretory/secretory (ES) products of the nematode as probe. Sequence analysis showed that they contained identical cDNA inserts of 606 bp, including a 5¢ non-translated region of 96 bp, a core translated segment of 408 bp and a poly(A) + 3¢ terminus. It encoded a novel 136-amino-acid polypeptide. Southern blot analysis indicated that the cDNA did not cross-hybridize to the genomic digests of T. spiralis, mouse, or rat. A single copy only of its complementary sequence was found in the genome of T. pseudospiralis. Using the lambda ZAP expression system, the cDNA was induced to express a 23-kDa b-galactosidase-fusion protein which did not cross-react with polyclonal and monoclonal antibodies against T. spiralis, heat shock proteins, or four heterologous species of nematodes. The antiserum against the fusion protein recognized a 15-kDa band from the ES products of T. pseudospiralis in immunoblotting. Immunocytolocalization demonstrated that the anti-fusion protein serum only recognized an epitope in the stichosome of T. pseudospiralis and not in T. spiralis. The protein can therefore serve as a speci®c antigen for the dierential diagnosis of trichinellosis.

Functional genes and proteins of Trichinella spp.

“…pseudospiralis-specific 15-kDa protein Chung and Ko (1999) reported that the protein with a molecular weight of 15 kDa is present in E-S products of T. pseudospiralis. This protein exists only in the stichocytes of T. pseudospiralis and not in T. spiralis.…”

Cloning and characterization of Clonorchis sinensis myoglobin using immune sera against excretory?secretory antigens

“…Moreover, the ES antigens or recombinant ES antigens of several parasites are reported to be useful in serodiagnosis (Chung and Ko 1999;D¢Souza and Hafeez 1999;Mehta et al 1999;Sadjjadi et al 2000;Yamasaki et al 2000;Carnevale et al 2001). The ES antigens of adult C. sinensis were investigated for use in serodiagnosis and it was reported that a 12.5-kDa and a 7-kDa antigen might serve as markers of active clonorchiasis (Kim 1994(Kim , 1998.…”

Proteomic analysis of excretory secretory products from Clonorchis sinensis adult worms: molecular characterization and serological reactivity of a excretory–secretory antigen-fructose-1,6-bisphosphatase

“…The excretory-secretory products (ESP) are known to involve in parasite-host interaction (Nagano et al 2009), and clinical significance in the diagnosis and pathogenesis (Chung and Ko 1999;Santra et al 2000;Yamasaki et al 2000). ESP play key roles in C. sinensis adults migrating to the intrahepatic bile ducts and subsequent cholangiocarcinoma (Kim et al 2009b;Pak et al 2009).…”