All factors related to each testing phase of specimen processing in the pathology laboratory may affect IHC staining.
Critical variables that affect staining results include:
- Temperature
- pH
- Ionic conditions
- Titer of antibody concentration
- Number of epitope sites per cell
- Duration of incubation
- Fixation and tissue processing
Quality Control (QC) Factors by Test Phase (not a complete list)
Pre Analytic | Analytic | Post Analytic |
Fixation: Time, type, volume | Heating, dewax, pretreatments | Localization, interpretation |
Tissue: Type, dimension | Antigen retrieval | Positive-negative tissue controls: Cut off values or scoring |
Tissue processing complete | Primary AB, dilution, clone, time, temperature | Report elements (eg, synoptic) |
Decalcification: Type, time | Detection: Sensitivity, selectivity | FDA disclaimers |
Section thickness, drying, storage | Controls | |