Section handling

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 (e.g., 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 lost.

 

Section storage

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 are preserved.

 

References

Williams Jhet al. J Clin Pathol 1997; 50: 422-8.

Jacobs TW et al. J Cancer Inst. 1996; 88:1054.