Advances in Clinical and Experimental Medicine

Title abbreviation: Adv Clin Exp Med
JCR Impact Factor (IF) – 2.1
5-Year Impact Factor – 2.2
Scopus CiteScore – 3.4 (CiteScore Tracker 3.7)
Index Copernicus  – 161.11; MNiSW – 70 pts

ISSN 1899–5276 (print)
ISSN 2451-2680 (online)
Periodicity – monthly

Download original text (EN)

Advances in Clinical and Experimental Medicine

2020, vol. 29, nr 6, June, p. 669–675

doi: 10.17219/acem/104554

Publication type: original article

Language: English

License: Creative Commons Attribution 3.0 Unported (CC BY 3.0)

Download citation:

  • BIBTEX (JabRef, Mendeley)
  • RIS (Papers, Reference Manager, RefWorks, Zotero)

The development and evaluation of a multi-epitope antigen as a serodiagnostic marker of Toxoplasma gondii infection

Abbas Alibakhshi1,A,B,D, Mojgan Bandehpour1,C,F, Zarin Sharifnia1,C,E, Bahram Kazemi1,A,F

1 Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Abstract

Background. Toxoplasma gondii (T. gondii) is a ubiquitous protozoan parasite which causes a serious disease called toxoplasmosis. The high prevalence of T. gondii infection has attracted a great deal of interest in its diagnosis and treatment. The use of pure antigens shows high sensitivity and specificity, but challenges such as cross-reactivity remain diagnostic difficulties.
Objectives. The aim of this study was to use 3 surface antigens (SAGs) of T. gondii to design gene-encoding a multi-epitope and immunogenic protein as a serodiagnostic marker.
Material and Methods. The multi-epitope antigen was expressed using Escherichia coli BL21 (DE3) cells and purified using affinity chromatography. To evaluate acute toxoplasmosis, 95 human sera with anti-T. gondii IgG, 25 human sera without anti-T. gondii IgG and 6 serum samples with nosocomial infections were collected and submitted to an enzyme-linked immunosorbent assay (ELISA) analysis. The potential of purified protein as a diagnostic marker of T. gondii infection was also investigated using ELISA analysis.
Results. The western blot analysis for both protein expression and purification confirmed that the protein was expressed and purified successfully. The results of validation showed a sensitivity of 72.6% and a specificity of 90.3% for recombinant ELISA.
Conclusion. Although this protein showed potential for detecting T. gondii, the sensitivity and specificity were lower than in tests that use the whole body of the parasite.

Key words

diagnosis, Toxoplasma gondii, multi-epitope antigen, surface antigens

References (14)

  1. Opsteegh M, Kortbeek TM, Havelaar AH, van der Giessen JW. Intervention strategies to reduce human Toxoplasma gondii disease burden. Clin Infect Dis. 2015;60(1):101–107.
  2. Hsu PC, Groer M, Beckie T. New findings: Depression, suicide, and Toxoplasma gondii infection. J Am Assoc Nurse Pract. 2014;26(11):629–637.
  3. Blader IJ, Coleman BI, Chen CT, Gubbels MJ. Lytic cycle of Toxo­plasma gondii: 15 years later. Annu Rev Microbiol. 2015;69:463–485.
  4. Dubremetz JF, Lebrun M. Virulence factors of Toxoplasma gondii. Microbes Infect. 2012;14(15):1403–1410.
  5. Lekutis C, Ferguson DJ, Grigg ME, Camps M, Boothroyd JC. Surface antigens of Toxoplasma gondii: Variations on a theme. Int J Parasitol. 2001;31(12):1285–1292.
  6. Montoya JG. Laboratory diagnosis of Toxoplasma gondii infection and toxoplasmosis. J Infect Dis. 2002;185(Suppl 1):S73–S82.
  7. Hajissa K, Zakaria R, Suppian R, Mohamed Z. Design and evaluation of a recombinant multi-epitope antigen for serodiagnosis of Toxoplasma gondii infection in humans. Parasit Vectors. 2015;8:315.
  8. Vita R, Overton JA, Greenbaum JA, et al. The immune epitope database (IEDB) 3.0. Nucleic Acids Res. 2015;43(Database issue):D405–D412.
  9. Saha S, Raghava GP. Prediction of continuous B-cell epitopes in an antigen using recurrent neural network. Proteins. 2006;65(1):40–48.
  10. Saha S, Raghava GPS. BcePred: Prediction of continuous B-cell epitopes in antigenic sequences using physico-chemical properties. In: Nicosia G, Cutello V, Bentley PJ, Timmis J, eds. Artificial Immune Systems: Third International Conference, ICARIS 2004, Catania, Sicily, Italy, September 13–16, 2004 Proceedings. Berlin-Heidelberg; Springer 2004:197–204.
  11. Larsen JE, Lund O, Nielsen M. Improved method for predicting linear B-cell epitopes. Immunome Res. 2006;2:2.
  12. Kolaskar AS, Tongaonkar PC. A semi-empirical method for prediction of antigenic determinants on protein antigens. FEBS Lett. 1990;276(1–2):172–174.
  13. Tomavo S, Schwarz RT, Dubremetz JF. Evidence for glycosyl-phosphatidylinositol anchoring of Toxoplasma gondii major surface antigens. Mol Cell Biol. 1989;9(10):4576–4580.
  14. Khanaliha K, Motazedian MH, Kazemi B, Shahriari B, Bandehpour M, Sharifniya Z. Evaluation of recombinant SAG1, SAG2, and SAG3 antigens for serodiagnosis of toxoplasmosis. Korean J Parasitol. 2014;52(2):137–142.