Open AccessImmunization against Egyptian Schistosoma mansoni infection by multivalent DNA vaccine
Author(s) -
Romeih Mahmoud H,
Hassan Hanem M,
Shousha Tarek S Abou,
Saber Mohamed A
Publication year - 2008
Publication title -
acta biochimica et biophysica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.771
H-Index - 57
eISSN - 1745-7270
pISSN - 1672-9145
DOI - 10.1111/j.1745-7270.2008.00404.x
Subject(s) - biology , dna vaccination , schistosoma mansoni , parasite hosting , plasmid , immune system , recombinant dna , microbiology and biotechnology , immunogenicity , virology , western blot , antigen , dna , gene , immunology , immunization , schistosomiasis , helminths , genetics , world wide web , computer science
The development of multivalent vaccines consisting of several antigens is a novel approach to creating broad‐range protection against different parasite strains and parasite life cycle stages. We have previously confirmed that the schisto‐some Sm 21.7 and Sm Fimbrin (SmFim) proteins could induce protection in mice. Therefore, this study aimed to construct themultivalentDNAvaccineS m 21.7‐S m Fim/pBudCE4.1and evaluate its immune efficacy. The open reading frames of two Schistosoma mansoni genes, Sm21.7 and SmFim , were inserted into the eukaryotic expression plasmid pBudCE4.1 designed for the independent expression of two genes in mammalian cells. To evaluate the in vitro expression of the multivalent Sm 21.7‐ Sm Fim/pBudCE4.1 DNA vaccine and its im‐munological effect in mice, the recombinant plasmid Sm 21.7‐S m Fim/pBudCE4.1 was used to transfect 293T cells, and the expression of mRNA and proteins was examined using reverse transcription‐polymerase chain reaction and Western blot analysis. Then the ability of Sm 21.7‐ Sm Fim/pBudCE4.1 to protect against S. mansoni challenge infections was analyzed according to worm burden and egg reduction rates after vaccination of mice. Vaccinated mice showed a significant level of protection (56%), and a decrease in the number and size, and change in the cellular profile, of granulomas. Egg reduction in liver and intestine was 41.53% and 55.63%, respectively, as determined relative to mice that received the empty vector only. In addition to reductions in worm viability, worm fecundity and egg hatching ability were observed following challenge infection in the immunized group. Results showed that Sm21.7‐S m Fim/pBudCE4.1 could express Sm2 1.7 and Sm Fim mRNA and proteins. Enzyme‐linked immunosorbent assay and Western blot analysis indicated that immunized mice generated specific immunoglobulin G against Sm 21.7‐S m Fim/pBudCE4.1. These results suggest that vaccination with multivalent S. mansoni DNA vaccine ( Sm Fim‐S m 21.7/pBudCE4.1) not only induces a significant reduction in worm and egg burdens, but also significantly reduces the size of egg granulomas. In summary, the multivalent vaccine stimulated specific immunity with a significant level of protection and has anti‐pathological effect.