Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. Benign or asymptomatic in most of cases, it presents a serious risk for pregnant seronegative women and subjects with a weakened immune system.
ELITech developed the ELI.H.A Toxo, an indirect hemagglutination assay, for the quantitative determination of anti- Toxoplasma gondii antibodies (IgG and/or IgM) in the serum. It is rapid, easy-to-use and easy-to-read with results available within 2 hours and reliable overnight.
Sheep red blood cells are sensitized with Toxoplasma gondii antigen. IgM as well as lgG antibodies are detected by this technique. They can be differentiated by treating serum with 2-mercaptoethanol (2-ME), which inhibits the agglutinating power of IgM.
Diluted serum is mixed with sensitized sheep red blood cells. If anti- Toxoplasma gondii antibodies are present in the serum, sensitized red blood cells will agglutinate, resulting in a cloudy red/brown deposit coating the well. In the absence of specific antibodies, sensitized red blood cells will not agglutinate, resulting in a ring-like deposit at the bottom of the well.
Non-sensitized red blood cells are also available in the kit. They ensure the specificity of the reaction by allowing identifying any interference from the natural anti-sheep agglutinins (Forssman heteroantibodies, infectious mononucleosis antibodies…).
The reaction is carried out in a U-microplate.
Each kit allows 120 tests to be carried out or 20 reactions of 6 dilutions. Results are obtained within 2 hours and are reliable overnight.
A SINGLE PROTOCOL FOR ALL OUR ELI.H.A KITS
Easy-to-read and easy-to-interpret result
NEGATIVE REACTIONNo anti-toxoplasma antibodies or non-detectable amount.Screening test: probably non-immune patient requesting a serological follow-up for pregnant women.
In case of potential acute infection: no toxoplasma infection or very recent beginning infection. Sample should be controlled with a 2nd sample to detect a possible appearance of antibodies.
Positive reactionPresence at a border-line level of anti-Toxoplasma gondii antibodies.Screening test: result to be interpreted according to the results obtained with other Toxoplasmaserology assays. If necessary control with a 2nd sample.
In case of potential acute infection or follow-up of non-immunized pregnant women: Suspicion of a current toxoplasmosis infection. Test for anti-Toxoplasma gondii IgM. It is recommended to control the result with a 2nd sample collected 15-21 days later.
Positive reactionPresence of anti-Toxoplasma gondii antibodies.Screening test: Probably a past infection (residual antibodies).
In case of potential acute infection or follow-up of non-immunized pregnant women: Probably an acute toxoplasmosis infection. Test for anti-Toxoplasma gondii IgM and control the result with a 2nd sample
Reagents and material
R1: Vial of2.4 mL of sensitized red blood cellsR2: Vial of 1mL of non-sensitized red blood cellsBUF: Vial of 55 mL of phosphate buffer pH 7.2
R3: Vial of 2 mL of adsorbent
CONTROL +: Vial of 0.2 mL of titrated positive control
CONTROL –: Vial of 0.2 mL of negative control
MICROPLATE : Microplate with a U-bottom
DROPPER: Special dropper
MATERIAL REQUIRED BUT NOT SUPPLIED
Automatic pipette(s) with a pipetting volume adapted to the volume that will be measured
Contaminated waste containers
2- mercaptoethanol (2-ME)
Stability and storage
The reagents are liquid and ready-to-use.
All the reagents are stored at 2-8°C. Do not freeze.
The results of the stability study indicate that the product has a stability of 24 months at 2-8°C from its manufacture.