Cloning, Expression and Immunization of the New
Antigen Gene Sj–Ts4 of Schistosoma japonicum
ZHOU Dong-Ming, YI Xin-Yuan*,
ZENG Xian-Fang, WANG Min, CAI Chun, WANG Qing-Lin, ZHANG Shun-Ke, MCREYNOLDS
Larry1
( Department of Parasitology, Xiangya School of Medicine, Central South
University, Changsha 410078, China; 1Molecular
Parasitology Group, New England Biolabs, Inc., MA 01915, USA
)
Abstract In order to
explore the molecular mechanism of high immune protection against schistosomes
infection in animals infected with Trichinella spiralis, and to provide
several cross-protective antigen genes for developing anti-schistosomiasis
vaccine, a Schistosoma japonicum adult worm cDNA library was
immunoscreened using sera taken from mice infected with Trichinella spiralis.
Nine positive clones were obtained after 3 rounds of immunoscreening. Among
them, Sj–Ts4 represents a novel gene of S. japonicum,
which coding for a novel protein of 210 amino acids. The protein has a deduced
molecular mass of 23 kD and isoelectric point of 7.72. Sj–Ts4 was
expressed as a glutathione-S-transferase (GST) fusion protein by cloning into
the prokaryotic expression vector pGEX-5X-3. The recombinant Sj-Ts4 protein
(rSj-Ts4) was purified and could be recognized by sera of miceinfected with S.japonicum.
Vaccination of several groups of mice with rSj-Ts4 or rSj-Ts4 incorporated into
Freund’s complete adjuvant induced high titers of specific IgG antibodies. Two
vaccination groups all obtained significant reduction in worm burden (31.36%,
36.80%, P<0.01),
compared with the control groups.
Key words Schistosoma japonicum; Trichinella spiralis; Sj–Ts4; molecular
cloning; immunization
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Fax, 86-731-4498311;
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