title: Sero-diagnostic evaluation of Toxoplasma gondii recombinant Rhoptry antigen 8 expressed in E. coli.
abstract: BACKGROUND
  Toxoplasma gondii infects all warm-blooded animals, including humans. Early diagnosis and determining the infective stage are critical for effectively treating immunosuppressed individuals and pregnant women with toxoplasmosis. Among the rhoptry proteins of the parasite, Rhoptry protein 8 (ROP8), is known to be expressed during the early stages of T. gondii infection and is involved in parasitophorous vacuole formation. In this study, we have investigated the diagnostic efficacy of recombinant ROP8 (rROP8).
  
  
  METHODS
  The ROP8 gene was cloned into pCOLD I DNA vector and expressed as a soluble recombinant antigen in Escherichia coli. Expressed ROP8 protein was evaluated using western blot method.
  
  
  RESULTS
  Western blot analysis of purified rROP8 antigen using 200 T. gondii-infected human serum samples, as well as non-infected serum controls, allowed for the successful identification of toxoplasmosis-positives, yielding a 90% sensitivity and 94% specificity.
  
  
  CONCLUSIONS
  Our findings indicated that rROP8 antigen expressed in E. coli was able to detect toxoplasmosis in infected human serum with specificity and sensitivity suggesting that rROP8 antigen represents a valid diagnostic marker for toxoplasmosis.
authors.forename: Parthasarathy
authors.initials: P
authors.lastname: Sonaimuthu
authors.forename: Mun Yik
authors.initials: MY
authors.lastname: Fong
authors.forename: Ramaswamy
authors.initials: R
authors.lastname: Kalyanasundaram
authors.forename: Rohela
authors.initials: R
authors.lastname: Mahmud
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia. lauyeeling@um.edu.my.
authors.forename: Yee Ling
authors.initials: YL
authors.lastname: Lau
mesh_terms: D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan; D015415:Biomarkers; D015153:Blotting, Western; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014122:Toxoplasma / Q000378:metabolism*; D014123:Toxoplasmosis / Q000097:blood / Q000175:diagnosis
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D015415:Biomarkers; D015800:Protozoan Proteins; C109324:ROP8 protein, Toxoplasma gondii; D011994:Recombinant Proteins