Recognition of non-specific staining

Staining of control slides without the application of the immune serum reveals endogenous enzyme activity cells devoid of the specific 

Non-specific adsorption of the immunoreactants can be recognized by a simple method. Serial sections of the tissue preparation are incubated with the reagent of the last step, of the last two steps, etc., e.g., one section with PAP, the second with bridging antibody plus PAP, etc. 

Immunological specificity is best inferred from neutralization or blocking tests. It is fallacious to deduct degrees of cross-reactivity or shared reactivity of a given antiserum in EIH from the results of EIA. Sensitivity and specificity are determined to a high degree by the design of the test as shown in Chapter 2 for the AA and the AM tests, and may, therefore, be very different in EIH and EIA. 

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