Friday, February 20, 2009

GRA2 and ROP1 recombinant antigens as potential markers for detection of Toxoplasma gondii-specific immunoglobulin G in human with acute toxoplasmosis

Clin Vaccine Immunol. 2009 Feb 18. [Epub ahead of print]

GRA2 and ROP1 recombinant antigens as potential markers for detection of Toxoplasma gondii-specific immunoglobulin G in human with acute toxoplasmosis

Holec-Gasior L, Kur J, Hiszczynska-Sawicka E.

Gdask University of Technology, Chemical Faculty, Department of Microbiology, Gdask, POLAND.

A goal of the current study was to evaluate serological applications of Toxoplasma gondii GRA2 and ROP1 antigens. Soluble recombinant GRA2 and ROP1 antigens as fusion proteins containing six histidyl residues at N- and C-terminal were obtained using an Escherichia coli expression system. Purification by a one-step metal affinity chromatography allowed recovery of milligram amounts of pure recombinant proteins per litre of culture. The usefulness of these antigens for diagnosis of human infections was tested on 167 serum samples obtained during routine diagnostic tests. A panel of 37 sera from patients with acute toxoplasmosis was compared to a panel of 90 sera from individuals with past infection. The results indicate that both GRA2 and ROP1 recombinant antigens detected antibodies more frequently from acute (100% and 94.6%, respectively) than from chronic infections (22.5% and 15.5% respectively). These results suggest that IgG antibodies against GRA2 and ROP1 antigens are produced during the acute stage of toxoplasmosis but are uncommon in the chronic phase of the infection. Hence, these recombinant proteins can be used as specific molecular markers to differentiate between acute and chronic infections.

PMID: 19225074 [PubMed - as supplied by publisher]

1 comment:

ummicro said...

I guess the big question for me is; does the parasite up-regulate its genes in the absents of certain immune functions? Or, does the immune system deregulate it's amplification in the presents of parasite carrying these antigens.
Case history of patients are big factors in these studies.
I assume the study group in acute cases have immunodeficiencies.