Prevalence of Toxoplasma gondii parasite in captive Mexican jaguars determined by recombinant surface antigens (SAG1) and dense granular antigens (GRA1 and GRA7) in ELISA-based serodiagnosis

Exp Parasitol. 2020 Jan:208:107791. doi: 10.1016/j.exppara.2019.107791. Epub 2019 Nov 5.

Abstract

Toxoplasma gondii is an obligate intracellular protozoan parasite that infects almost all warm-blooded animals, including humans, causing serious public health problems. In this study, the seroprevalence of T. gondii in captive jaguars in 10 Mexican zoos was determined using single and mixtures of recombinant surface antigens (SAG1) and dense granular antigens (GRA1 and GRA7) in immunoglobulin G (IgG) enzyme-linked immunosorbent assays (ELISAs). Their efficacy was compared with the tachyzoite lysate antigen. All recombinant antigens were characterised by high sensitivity (92.5-97.5%); the specificity of the IgG ELISAs was variable (83.3-91.6%). Mixtures of the two recombinant proteins were generally more reactive than single antigens. GRA7 + SAG1 showed the highest sensitivity (97.5%) and specificity (91.6%), almost perfect agreement (96.2%), and a kappa value of 0.89. An area under the curve value of 0.998 represented a highly accurate test with a cutoff value of 0.8. The seroprevalence of anti-T. gondii IgG antibodies in the single and mixed recombinant antigen ELISAs was 75.0-76.9%. This study shows that GRA7 + SAG1 can be successfully used to diagnose T. gondii infection in jaguars for effective monitoring of prevalence and for devising control methods and prevention strategies against toxoplasmosis.

Keywords: ELISA; Jaguars; Mexico; Prevalence; Recombinant antigens; Serodiagnosis; Toxoplasma gondii; Zoo.

MeSH terms

  • Animals
  • Animals, Zoo
  • Antigens, Protozoan / immunology*
  • Area Under Curve
  • Enzyme-Linked Immunosorbent Assay / veterinary
  • Female
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Male
  • Mexico / epidemiology
  • Panthera / parasitology*
  • Prevalence
  • Protozoan Proteins / immunology*
  • Protozoan Proteins / standards
  • ROC Curve
  • Recombinant Proteins / immunology
  • Recombinant Proteins / standards
  • Sensitivity and Specificity
  • Seroepidemiologic Studies
  • Toxoplasmosis, Animal / diagnosis
  • Toxoplasmosis, Animal / epidemiology*
  • Toxoplasmosis, Animal / immunology
  • Toxoplasmosis, Animal / prevention & control

Substances

  • Antigens, Protozoan
  • GRA1 antigen
  • GRA7 protein, Toxoplasma gondii
  • Immunoglobulin G
  • Protozoan Proteins
  • Recombinant Proteins
  • SAG1 antigen, Toxoplasma