Frequently Asked Questions

Read our frequently asked questions here, along with tips on how to make the most out of our services

Old tissue is often poorer quality than newer tissue. We recommend re-embedding in fresh wax prior to use.
Tissue is better preserved in the block than on the slide, for example, historically cut slides often give poorer staining. We recommend sectioning close to the staining date.
Optimal formalin fixation results in better IHC or multiplex staining.
There should only be one tissue section per slide.
Place tissue as centrally as possible on the slide.
If intending to overlay images for analysis, tissue placement and orientation must be as similar as possible across each slide.
Thick tissue sections give poorer quality staining. 5-micron sections are recommended.

Please see the FAQ ‘What factors affect the quality and consistency of multiplexed images?’ for further multiplex related considerations.

What factors affect the quality and consistency of brightfield images?

Staining is dependent on antibody quality and epitope expression levels.
Endogenous pigment can interfere with analysis in bright field imaging (melanin, carbon, tattoo, haemosiderin). We recommend choosing an appropriate coloured chromogen.
Targets where there is a validated clinical grade antibody will show better results.
Cell localised targets, rather than connective tissue or stroma localised tissue, will often give better analysis results.

Adipose (fat) rich areas, such as those within breast and pancreas tissue, can show poor staining and are prone to lifting off the slide. TOMO slides are always recommended in these tissues.
Calcifications, which occur in tissues such as breast and serous tumours, can cause artefactual defects in tissue.
Tissues rich in endogenous peroxidases such as muscle and liver often show more non-specific staining.