Tissue handling ■
Section handling ■
Epitope retrieval ■
Primary antibody ■ Visualization ■ Chromogene ■ Controls ■ Recommended control tissue
Section mounting and drying
In order to minimise
detaching - particularly during subsequent heat induced
epitope retrieval (HIER) - 3-4 mm sections should be mounted on slides, which are either coated
poly-L-lysine or silane) or electrostatically treated (e.g.,
SuperFrost®Plus). Partly detached sections may give rise
to false positive stainings due to entrapment of reagents.
Drying at 37°C overnight followed by 60°C for one hour is
usually sufficient for the adherence and does not hamper the
antigeneity. If the temperature is increased to 80°C or
drying is carried out on a hot plate, some antigens may be
Tissue sections kept at room
temperature for more than a few weeks show progressive and
irreversible loss of some epitopes, particular nuclear
antigens like estrogen receptor protein. In contrast,
keeping the slides at -80°C preserves the antigeneity. Also
in paraffin blocks stored at room temperature, the antigens
Williams Jhet al. J Clin Pathol 1997; 50: 422-8.
Jacobs TW et al. J Cancer Inst. 1996; 88:1054.