General Microtome Sectioning of Formalin-Fixed Paraffin Embedded (FFPE) blocks
Toby J Curless, Zane Jaunmuktane
Abstract
This protocol describes the steps for the sectioning of formalin-fixed paraffin embedded blocks in preparation for further tissue processing such as immunohistochemistry.
Before start
Check all equipment, supplies and consumables* Set-up water bath to required temperature
- Ensure blade is fit-for-purpose and clean
- Label/barcode SuperFrost Plus slides
Steps
Preparation
Check all equipment, consumables and supplies are in place.
Place a clean blade into the blade holder of the microtome.
Place the FFPE block onto ice, with the face of the block on the surface of the On ice until the block is cold through.
Heat 1L distilled H2O to40°C in a water bath.
Sectioning
Once both block and water are at the correct temperature, insert the block into the chuck of the microtome.
Adjust the levers on the microtome to position the face of the block parallel with the blade.
Lower the block until it is level with the blade and move the block closer to the blade using the handle on the microtome.
Select the thickness of choice on the microtome (usually 4-7 µm .
Section and trim into the block until the whole tissue cross-section is present in the sections.
Using tweezers or a fine paintbrush, gently pull sections down until a ribbon of tissue sections has formed.
Pick up the ribbon with tweezers and place into the water bath to allow wrinkles to disappear from the tissue.
Separate sections using tweezers and collect individual sections on SuperFrostTMcharged microscope slides.
Allow slides to drain and air dry vertically at Room temperature for > 12h 0m 0s prior to further processing.
