Toxoplasmosis IgM/IgG Test

 Toxoplasmosis is a common parasitic infection caused by an obligate intracellular protozoan, T. gondii, which is widespread throughout the World. Although T. gondii infection is generally asymptomatic in healthy adults, it may lead to severe conditions in immunosuppressed individuals including patients with AIDS and the developing fetus. T. gondii infection in the immunosuppressed patients causes encephalitis, pneumonia, and disseminated infection. 

Transplacental transmission of the parasite may occurs during the first two trimesters of pregnancy and can severely damage the fetus, which eventually causes irreversible neurological damages, neonatal malformations, blindness, or fetal death. 

Therefore, diagnosis of toxoplasmosis presents an essential measure for the disease control. Various methods can be achieved including indirect fluorescent-antibody test, tissue culture, PCR, and rapid immunoassay. Serological diagnosis can establish current and past infections with T. gondii. The antibody response to T. gondii is highly specific. Detection of IgG antibodies to T. gondii indicates that individuals have past infections, while detection of IgM antibodies to T. gondii signifies a current and acute infection. 

The TOXO IgG/IgM Rapid Test Device (Whole Blood/Serum/Plasma) is a lateral flow immunoassay to differentially detect the IgG and IgM antibodies specific to T. gondii, and will present a presumptive diagnosis of T. gondii infection.

Principle

 The TOXO IgG/IgM Rapid Test Device detects IgG and IgM antibodies to T. gondii through visual interpretation of color development. Recombinant antigens of T. gondii, anti-human IgG and anti-human IgM antibodies are used to detect the specific antibodies in the human whole blood, serum or plasma samples. When a sample is added to the sample well on the test panel, T. gondii IgG antibodies, if present, will bind to the recombinant T. gondii antigens conjugated to colored particles on the sample pad. As the specimen migrates along the strip by capillary action and interacts with reagents on the membrane, the complex will be captured by anti-human IgG and/or anti-human IgM antibodies immobilized at the detection zone. Excess colored particle are captured at the internal control zone. 

The presence of a red band(s) in the test region indicates a positive result for the particular IgG and/or IgM antibodies, while its absence indicates a negative result. A red band at the control region (C) serves as a procedural control, indicating that the proper volume of specimen has been added and membrane wicking is working.