Mycoplasma pneumoniae IgA ELISA
The IMMUNOLAB Mycoplasma pneumoniae IgA antibody ELISA kit has been designed for the detection and the quantitative determination of specific IgA antibodies against Mycoplasma pneumoniae in serum and plasma. Further applications in other body fluids are possible and can be requested from the Technical Service of IMMUNOLAB.
Mycoplasms belong to the Mollicutes class. Common characteristics of the six eubacterial genera is the lack of a bacterial cell wall, osmotic fragility and small dimensions, which allow a penetration through a 0.45 μm filter. Also the genome with 600 kbp is significantly smaller compared with gram-positive and gram-negative bacteria. Out of this reason they have never been found as freely living organisms. In nature Mollicutes depend on a host cell, respectively, on a host organism like a parasite.
Mycoplasma pneumoniae is a human pathogenic bacterium causing tracheobronchitis and primary atypical pneumonia. Associated with the host cell, surface colonization of human respiratory tract epithelial cells takes place. Also secondary diseases like infarction, encephalitis, chronic neuropathy and the Guillain-Barre syndrome can in some cases be connected with a M. pneumoniae infection. In the laboratory, M. pneumoniae can be grown without a host cell in rich medium supplemented with 10-20% horse serum. Besides the cold agglutinin test and complement fixation reaction CF, ELISA is the method of choice, which shows an excellent sensitivity and the possibility to differentiate between the immunogloblin classes.
Specific IgA antibodies were developed more regularly and more rapidly than IgM during an acute infection. IgA titres also started to decrease earlier than IgM or the late-peaking IgG response.
It could be shown in various studies, that the determination of all the three immunoglobulin classes is necessary, to monitor each step of the clinical course.
The IMMUNOLAB Mycoplasma pneumoniae IgA antibody test kit is based on the principle of the enzyme immunoassay (EIA). Mycoplasma pneumoniae antigen is bound on the surface of the microtiter strips. Diluted patient serum or ready-to-use standards are pipetted into the wells of the microtiter plate. A binding between the IgA antibodies of the serum and the immobilized Mycoplasma pneumoniae antigen takes place. After a one hour incubation at room temperature, the plate is rinsed with diluted wash solution, in order to remove unbound material. Then ready-to-use anti-human-IgA peroxidase conjugate is added and incubated for 30 minutes. After a further washing step, the substrate (TMB) solution is pipetted and incubated for 20 minutes, inducing the development of a blue dye in the wells. The color development is terminated by the addition of a stop solution, which changes the color from blue to yellow. The resulting dye is measured spectrophotometrically at the wavelength of 450 nm. The concentration of IgA antibodies is directly proportional to the intensity of the color.
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