Histology Sectioning

It is important to have a properly fixed and embedded block or much artefact can be introduced in the sectioning.

Histology sectioning. Sectioning tissues is a real art and takes much skill and practice. In histology sectioning refers to the service of cleanly and consistently cutting paraffin embedded or frozen tissue into a thin slice. For staining paraffin sections of tissue are normally used.

Histotechnologists are the artists of the laboratory. The labeled end is towards you. Thin sections are cut which can be stained and mounted on a microscope slide.

Sectioning once embedded tissues are cut into thin sections ready to be placed on a slide. The tissue is trimmed and mounted on a cutting device called a microtome shown in the picture. There are two main categories of sectioning referred to as paraffin or frozen sectioning.

Alcohol based fixatives generally do not give good morphology but may be useful in special cases such as brdu staining. Histology is the microscopic counterpart to gross anatomy which looks at larger structures visible without a microscope. Common artefacts include tearing ripping venetian blinds holes folding etc.

Paraffin blocks can be sectioned with high carbon steel blades. Common examples include oil red o staining for lipids removed during paraffin processing and antibodies whose epitopes are masked or destroyed by the ethanols and xylenes and heat involved with paraffin processing. Histology also known as microscopic anatomy or microanatomy is the branch of biology which studies the microscopic anatomy of biological tissues.

These thin slices are referred to as sections and are then mounted to a slide. Optimal histology requires adequate fixation about 48 hrs at room temperature for thinly sliced tissues. A huge range of stains is used in histology from dyes and metals to labeled antibodies.