The process of histological sectioning typically involves several key steps:
Fixation
Fixation preserves the tissue and prevents degradation. Common fixatives include formaldehyde and glutaraldehyde. Fixation maintains the tissue's structural integrity and prevents autolysis and putrefaction.
Embedding
After fixation, tissues are embedded in a solid medium, usually paraffin wax, to provide support and maintain tissue structure during sectioning. Embedding involves multiple steps, including dehydration, clearing, and infiltration.
Sectioning
Sectioning involves cutting the embedded tissue into thin slices using a microtome. The thickness of these sections can range from 3 to 10 micrometers, depending on the type of tissue and the intended analysis.
Mounting
The thin tissue sections are placed onto glass slides and allowed to adhere. Proper mounting ensures that the sections remain flat and intact during staining and examination.
Staining
Staining enhances the contrast of the tissue sections, making cellular structures more visible under a microscope. Common stains include Hematoxylin and Eosin (H&E), which stain nuclei blue and cytoplasm pink, respectively.
