caa a22 4500 44534024X CHVBK 20180317142810.0 cr unu---uuuuu 170323e20110901xx s 000 0 eng 10.1007/s00436-011-2315-6 doi (NATIONALLICENCE)springer-10.1007/s00436-011-2315-6 Immunogenic characterization of the chimeric surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii expressed in the yeast Pichia pastoris [Elektronische Daten] [Yee Lau, Girija Thiruvengadam, Wei Lee, Mun Fong] In this study, we successfully expressed a chimerical surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii in Pichia pastoris. Eighty human serum samples, including 60 from confirmed cases of toxoplasmosis, were tested against the purified recombinant SAG1/2 in Western blots. Results of Western blots targeted at Toxoplasma IgG and IgM showed that the recombinant SAG1/2 reacted with all sera from the toxoplasmosis cases but none with the Toxoplasma-negative serum samples. These results showed that the P. pastoris-derived recombinant SAG1/2 was sensitive and specific and suitable for use as antigen for detecting anti-Toxoplasma antibodies. To further investigate the immunological characteristic of the recombinant protein, the recombinant SAG1/2 was injected subcutaneously into BALB/c mice, and their serum was tested against total protein lysate of T. gondii. Mice immunized with the recombinant SAG1/2 reacted specifically with the native SAG1 and SAG2 of T. gondii. Significant proliferation of splenocytes stimulated with tachyzoite total protein lysate was observed in vaccinated BALB/c mice but not in those from negative control mice. Specific production of IFN-γ, the Th1-type cytokines, was also found in stimulated splenocytes from vaccinated mice. These results show that the chimeric protein recombinant SAG1/2 can elicit a Th1-associated protection against T. gondii infections in mice. Finally, vaccinated mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P < 0.005), and their survival time increased significantly compared to the negative control. Springer-Verlag, 2011 Lau Yee Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut Thiruvengadam Girija School of Science, Monash University Sunway Campus, 46150, Bandar Sunway, Selangor, Malaysia aut Lee Wei Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut Fong Mun Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut Parasitology Research Springer-Verlag 109/3(2011-09-01), 871-878 0932-0113 109:3<871 2011 109 436 https://doi.org/10.1007/s00436-011-2315-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00436-011-2315-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lau Yee Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut NATIONALLICENCE 700 1- Thiruvengadam Girija School of Science, Monash University Sunway Campus, 46150, Bandar Sunway, Selangor, Malaysia aut NATIONALLICENCE 700 1- Lee Wei Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut NATIONALLICENCE 700 1- Fong Mun Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia aut NATIONALLICENCE 773 0- Parasitology Research Springer-Verlag 109/3(2011-09-01), 871-878 0932-0113 109:3<871 2011 109 436 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer