What is the expected effect of human serum contaminating the AHG stock solution in the AHH-CDC assay?

In the context of the AHH-CDC assay, human serum contaminating the antihuman globulin (AHG) stock solution can indeed lead to many false negative reactions. This is primarily due to the fact that the presence of additional human immunoglobulins can interfere with the assay's ability to detect the specific binding of antibodies that would typically signal a positive reaction.

When human serum is mixed in with the AHG, it may saturate the available binding sites on the globulins, thus preventing the assay from accurately identifying and agglutinating the target cells. This results in a scenario where the assay fails to show a positive response when it should, leading to a false negative outcome. Such interference is significant in the laboratorial evaluation of potential transplant matches and other serological testing where accurate results are critical.

The situation is complicated further if we consider that the AHH-CDC assay relies on the clear recognition of antibodies. With the introduction of human serum, there is a risk that the assay will miss homologous reactions (where the antigen and antibody should have a clear interaction), as the antibody levels can be diluted or masked by the contaminating serum.