Toxoplasma gondii: Cloning, expression and immunoreactivity of recombinant ROP5 and ROP18 antigens

• Published in: Experimental parasitology 2015-03, Vol.150, p.1-6
• Main Authors: Grzybowski, Marcin M., Dziadek, Bożena, Dziadek, Jarosław, Gatkowska, Justyna, Dzitko, Katarzyna, Długońska, Henryka
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Protozoan - blood; Antigens, Protozoan - genetics; Antigens, Protozoan - immunology; Cloning, Molecular; E. coli expression system; Escherichia coli; Gene Expression Regulation, Enzymologic; Immunoglobulin G - blood; Immunoglobulin M - blood; Male; Mice; Mice, Inbred C57BL; Murine toxoplasmosis; Protein-Serine-Threonine Kinases - genetics; Protein-Serine-Threonine Kinases - immunology; Recombinant antigen; Recombinant Proteins - genetics; Recombinant Proteins - immunology; ROP18; ROP5; Toxoplasma - enzymology; Toxoplasma - genetics; Toxoplasma - immunology; Toxoplasma gondii
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1016/j.exppara.2015.01.006

•We generated five recombinant forms of Toxoplasma gondii ROP5 and ROP18 in E. coli.•Recombinant ROP5 and ROP18 were recognized by the sera of T. gondii-infected mice.•Anti-ROP IgM antibodies seem to be an early and sensitive marker of toxoplasmosis. Early diagnosis and determining the infective stage are critical for effective therapy of toxoplasmosis. Owing to the progress in biotechnology, commonly used native, non-standardized diagnostic antigens should be replaced by genetically engineered antigens. The recombinant proteins are also promising components of subunit vaccines against Toxoplasma gondii infections. A strategic biological role of rhoptry proteins (ROP) in parasitophorous vacuole biogenesis and virulence of the parasite creates a necessity for an intensive study on the serological activity and immunogenicity of newly developed recombinant ROP antigens. Our findings indicate that all generated preparations of recombinant ROP5 and ROP18 antigens, expressed in Escherichia coli bacteria, are recognized by specific antibodies produced during acute and chronic infections in inbred laboratory mice. We noticed, for the first time, that ROP5 IgM antibodies are an early and sensitive marker of T. gondii infection. The proven immunoreactivity of the obtained preparations has become a premise for a further study on their utility in routine diagnosis of human and animal toxoplasmosis as well as in the immunoprevention of T. gondii infection (as the main or supplementary component of the vaccine).