Nonspecific binding endogenous antibodies

The difficulties that arise from nonspecific binding of incubated antibodies to charged groups, Fc receptors, and endogenous antibodies are major problems for immunocytochemistry (Fig. 5.2). 

Fig. 5.2 Examples of nonspecific antibody binding. During immunocytochemistry incubations nonspecific binding occurs. The correct antigen will bind the primary antibody correctly. Charged groups will bind to any protein or antibody such as the 1° antibody. The Fc receptor will bind the first antibody that comes in contact here with the 1° antibody. Any endogenous antibodies are likely to bind only to secondary antibodies made against the species of the animal...

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