SOMETIMES, OLD PRODUCTS CAN FIND NEW EXCITING APPLICATIONS

A LEAP AHEAD IN QUALITY CONTROL FOR HISTOLOGY AND MOLECULAR TECHNIQUES

Tissue microarrays have been around for a long time now and they are a very interesting technique to simplify quality control, by placing a great number of different tissues on a single slide.

The technique is well known, tissue blocks of interest are selected and a representative core sample is taken. It is then inserted in a receiver paraffin block that offers a variable number of holes and a block is created that can then be cut to make multiple sample slides.

The technique is now mastered by many,  as the components and tools to make the TMAs are readily available. Simport offers the T-Sue™ series that includes the molds to make your own receiver blocks or ready-made receiver blocks,  as well as the different size punch tools to pick up the tissue samples.

The technique has now evolved to enable the making of fresh tissue microarrays. This offers multiple advantages. Fresh tissue has not been fixed which makes it more suitable for any immunohistochemistry technique. Antibody/antigen binding is often hampered by the protein cross-linking of the fixative that masks the tissue antigens which reduces or obliterates signal altogether. It also enables molecular biology techniques like RNA in-situ hybridization. Using FFPE for molecular assays has been and remains a challenge so to think that there is a technique offering you good QC material for ISH is really a major improvement in today's histology techniques!

How can these fresh tissue microarrays (should we call them FTMA?) be prepared? You’ll need a cryostat for starters. Then, simply prepare the receiver blocks with OCT instead of paraffin. Our molds will accommodate this. The rest is simple. Pick the tissue core with the proper tool from a fresh tissue that was previously frozen and insert it in the holes of the receiver block. Then, cut in the cryostat at a thickness of 5 microns.

The end result will offer you a fresh tissue microarray. The morphology will be better than fixed tissue, the IHC S/N ratio will be improved and enable skipping the demasking step and these will also be readily available for FISH quality control. A dream come true!

Additional information on the tools and products is available from Simport’s website Tissue Microarray - Simport or in real-time on the phone or by a chat with our technical support team.

If you are already preparing fresh tissue microarrays, please share below what your experience is, what are the hurdles, and recommendations for a successful result.