The hematoxylin and eosin (H&E) stain is the primary diagnostic stain performed on all formalin-fixed skin samples. This stain paints a basic picture of the different cells and structures in skin, as well as their relationship. This section summarizes the results of the H&E stain with a focus on identification of major skin cells and structures in a properly stained skin slide. Although histologists do not diagnose skin disorders, they should be able to recognize the various skin components. This knowledge is critical to creating and troubleshooting high-quality stains.
We will now take a closer look at a properly stained H&E skin cross-section, as displayed in the image. Identify as many layers, cells, and structures as possible.
- Note the clearly defined blue nuclei throughout the section that have been stained by hematoxylin. Nuclei are crisp and the nucleolus can be identified in some cells, as well as chromatin. The nuclear membrane is also a dark blue.
- Identify the three distinct shades of pink/orange stained by eosin. Red blood cells (RBCs) are the darkest shade; muscles and connective tissue are a lighter orange; and finally, cytoplasm in the cells is the faintest pink.
- Notice the different layers of cells, some of which have nuclei and some do not. Name the three major layers.
- Note the finger-like projections between the layers. Are dermal papillae present?
- Is there melanin pigment present near the melanocytes?
The following sections explain the cellular and structural details of skin samples.