The hook effect or the prozone effect is a type of interference which plagues certain immunoassays and nephelometric assays, resulting in false negatives or . objetivos: conocer las diferentes técnicas de aglutinación usadas en el laboratorio. adquirir habilidad y destrezas en las técnicas de. Prozone effect: No prozone effect was detected upon mg/dL. 4. . Efecto prozona: No se observa efecto prozona hasta valores de
AGLUTINACION Y FLOCULACION by Emanuel Barrios on Prezi
In an agglutination test, a person’s serum which contains antibodies is added to a test tubewhich contains a particular antigen. The hook effect or the prozone effect is a type of interference which plagues certain immunoassays and nephelometric assaysresulting pozona false negatives or inaccurately low results.
Thus the proper precipitation reaction does not take place. The range of relatively high antibody concentrations within which no reaction occurs is called the prozone. Examples include high levels of syphilis antibodies in HIV patients proaona high levels of cryptococcal antigen leading to false negative tests in undiluted samples.
This page was last edited on 14 Augustat If the antibodies agglutinate with the antigen to form immune complexesthen the test is interpreted as positive. However, if too many antibodies are present that can bind to the antigen, then the antigenic sites are coated by antibodies, and few or efrcto antibodies directed toward the pathogen are able to bind more than one antigenic particle.
The effect can also occur because of antigen excess, when both the capture and detection antibodies become saturated by the high analyte concentration. In this case, free antigen is in competition with captured antigen for detection antibody binding.
Retrieved 3 February In this case, the result is a false negative. Retrieved from ” https: Other common forms of interference include antibody interference, cross-reactivity and signal interference.
Has its time arrived? In this case, no sandwich can be formed by the capturing antibody, the antigen and the detection antibody.
The serological test is mainly seen in the precipitation reaction. Because no agglutination occurs, the test is interpreted as negative.
Views Read Edit View history. From Wikipedia, the free encyclopedia. However, when the serum is diluted, the blocking antibody is as well and its concentration decreases enough for the proper efeto reaction to occur. The antibody that fails to react is known as the blocking antibody and prevents the precipitating antibody from binding to the antigens.