Dr Vivien Rolfe De Montfort University This is an Open Educational Resource (OER) that is globally available on the web Creative Commons BY SA.

Dr Vivien Rolfe De Montfort University This is an Open Educational Resource (OER) that is globally available on the web Creative Commons BY SA

Why are special stains still important and relevant today? What are some of the chemical principles behind these stains? Some common examples that can be prepared in student laboratory teaching.

H&E was first introduced in the 1870s and the term special stain came to refer to any technique other than H&E used in the clinical environment. Whilst the H&E stain is the most common staining method in hospital and research laboratories, it isnt without its limitations. H&E cannot visualize micro-organisms. H&E is not good for distinguishing connective tissue and nerve tissue. H&E cannot distinguish molecular basis of disease and immunohistochemistry might be preferred.

Tolonium Chloride Useful blue cationic dye Cheap and simple application

Immunohistochemical methods have advanced but are costly and reagents deteriorate quickly. Special stains include silver methods (such as Gordon and Sweets), gold, or Luxol fast blues to stain myelin. Other special stains identify nerve cells. The techniques are important for looking and neurodegeneration.

One of several silver methods for staining reticulin. Tissue treated with potassium permanganate to enable the silver to bind. Uses an ammoniacal silver solution. What is reticulin? Why is it important?

Liver tissue with no counterstain Reticulin = black

Liver counterstained with what? Reticulin = black Cytoplasm = pink

Trichrome stain producing 3 colours. Anionic dye and a cationic counterstain. Nuclear stain applied first such as Weigerts haematoxlin. Collagen stains red with acid fuchsine. Cytoplasm including muscle stains yellow. Washing in acidified water differentiates tissue producing two colours.

Bladder Collagen = red All other tissue including transitional epithelium = yellow

Collagen = red Smooth muscle = yellow Epithelium = yellow Application? Might be used to localise tumours in the bladder to either the smooth muscle or connective tissue layers.

Trichrome stain. Martius yellow and phosphotungstic acid. Brilliant crystal scarlet. Methyl blue. What do the dyes stain?

Epithelium = red Collagen = blue Cytoplasm = red No visible yellow

Collagen = blue Erythrocytes and early fibrin = yellow Cytoplasm = pink

Erythrocytes clearly yellow Collagen = blue Cytoplasm = red

Early fibrin deposits = diffuse yellow staining Collagen = blue Glandular tissue = red

Trichrome stain. Iron-haematoxylin plus two anionic dyes. MSB is a variation of this. Iron-haematoxylin. Scarlet-acid fuchsine. Light green (more of a turquoise stain).

Nuclei = black Cytoplasm including muscle and epithelium = red Erythrocytes = red Collagen = bluey green or turquoise

MSB Collagen = bluey green Cytoplasm of epithelium and skeletal muscle = red

Histological and Histochemical Methods. 4 th Edition. By JA Kiernan. 2007. Scion publishing. Available: http://www.scionpublishing.com Histopathology: Fundamentals of Biomedical Science. By G Orchard and B Nation. 2012. Oxford University Press. Available: http://www.oup.com/uk/orc/bin/fbs/ Laboratory skills open educational resources. De Montfort University. Available: https://www.youtube.com/user/biologycourses

Dr Vivien Rolfe De Montfort University This is an Open Educational Resource (OER) that is globally available on the web Creative Commons BY SA.

Documents

red slide

black slide

pink slide

turquoise slide

sa slide

visible yellow slide

simple application slide

red collagen