Tissue Sectioning

Slide Pre-Treatment

The following pre-treatment procedure is designed to prevent peeling caused by elevated temperature, high pressure, radiation and other factors.

  • Microscopic Slide
    Due to the oil attached on surface, a new slide should be dipped into cleaning solution for 12 to 24 hours. After washing the slide more than 5X in distilled water, dip it into 95% alcohol for 2 hours followed by drying with simple wiping or in an infrared oven. Pay attention to avoid scratching the slide during washing.Note: Microscopic slide for IHC is required to be 5 μm. However, the slide for nervous tissue should be 20-100 μm to enhance the tracking of never fiber direction.
  • Coverslip
    The coverslip pre-treatment procedure is very similar to the one for the microscopic slide except that dipping and cleaning should be completed in 2 hours because the coverslip is much thinner.
  • Tissue Section Mounting
    • Dilute 3-Amino Propyl Tri-ethoxy Silane (APES) by acetone
    • Coat the microscopic slide with APES
    • Apply tissue on the coated slide followed by adding a drop of mounting medium (Glycerol Gelatin) on the tissue
    • Hold the coverslip at 45°, allowing the drop to spread along the edge of the slip
    • Slowly cover the tissue entirely with the coverslip
    • Incubate the slide at 80℃ for 1 hour if there is an adhering problem with a tissue section

Tissue Section Types

  • Frozen
    The most important feature for this type of tissue section is to keep antigen’s immune-competence completely, especially for the cell surface antigen. Both fresh and fixed tissues can be processed as frozen tissues. However, the tissues must be dried (or primary fixed) and stored at low temperature.
  • Paraffin-Embedded
    Paraffin-embedded tissue section is normally sliced by a rotary microtome to give a thickness of 2-7 μm. With proper treatment, the section reveals clear tissue structure and exact antigen location to enable high medical-value pathology researches and retrospective studies. This section type can be stored at 4℃ for long term use.

Processing

  • Cell on Coverslip
    • Place settled coverslip in culture bottle or perforated plate
    • Take out coverslip after cell growth has reached 60%
    • Fix coverslip with cold acetone or 4% paraformaldehyde for 10 to 30 min
    • Store cell (in gelatin) at -20℃
  • Cell Smear
    • Collect non-adherent cells and wash 2X by cold PBS buffer
    • Re-suspend cells with PBS buffer
    • Add 30-50 µL to settled slide and smear it evenly
    • Air dry slide a little bit and cover cell with 4% paraformaldehyde for 2-4 hours
    • Store cell (in gelatin) at -20℃