Histochemical and Immunohistochemical Staining Methods

Vocabulary flashcards for review of histochemical and immunohistochemical staining methods.

Histochemistry

Special staining methods used to visualize specific structural and molecular components in tissue.

Immunohistochemistry

Histologic method to identify tissue antigens using specific antibodies.

PAS reaction

Histochemical method for the proof of glycogen, reticular fibers, mucus, and basement membrane.

Coupling azo dye method

Histochemical method for the proof of enzymes (alkaline phosphatase).

Antigen (Ag)

Molecule triggering antibody (Ab) production.

Monoclonal Antibody

Antibodies generated by a single B-cell clone that recognize a single epitope.

Polyclonal Antibody

Antibodies generated by different B-cell clones directed against various epitopes of the same antigen.

Direct IHC method

Reaction of labeled primary antibody with the tissue antigen; fast but not very sensitive.

Indirect IHC method

Reaction of unlabeled primary antibody with antigen, followed by reaction of labeled secondary antibody with primary antibody; more sensitive.

PAP

Peroxidase-antiperoxidase, a tertiary antibody complex used in indirect three-step IHC methods.

APAAP

Alkaline phosphatase-anti alkaline phosphatase, a tertiary antibody complex used in indirect three-step IHC methods.

ABC

Avidin-biotin complex, a tertiary antibody complex used in indirect three-step IHC methods.

Mitochondria

Semiautonomous organelles that generate ATP and initiate apoptosis; present in most cells except erythrocytes and terminal keratinocytes.

Ki-67

Nuclear protein; marker of cell proliferation, used as a prognostic factor in tumor diagnostics.

E-cadherin

Ca2+-dependent transmembrane protein; marker of epithelial cells, important for cell adhesion, tissue integrity, and signal transmission.

CD68

Cytoplasmic protein of cells of the mononuclear phagocyte system (macrophages, monocytes, dendritic cells).

Cytokeratins

Cytoplasmic intermediate filaments that form the cytoskeleton of cells of epithelial origin; tissue and organ specific.

Cytokeratin 7

Cytoplasmic intermediate filament expressed strongly in duct cells of glandular epithelium.