STAINS FOR MUCIN www.pgmeeuploads.com
 PAS (peroidic acid-Schiff) Stains glycogen as well as mucins, but tissue can be pre-digested with diastase to remove glycogen Ie PAD ( peroidic acid-Schiff after diastase digestion) stains mucin and not glycogen.
Q . Which stain is used to demonstrate Glycogen in liver sections in case of glycogen storage disorder ? www.pgmeeuploads.com
Ans = PAS & PAD [ PAS will stain + whereas PAD becomes Negative]
 Colloidal iron
 Alcian blue - Stains acidic mucin blue ( See image below which shows blue staining of goblet cells in section from Colon ) www.pgmeeuploads.com
NOTE - The mucin stain with the most specificity is mucicarmine, but it is very insensitive, so it is not really very useful. The stain that is the most sensitive is PAS. www.pgmeeuploads.com
 Fontana-Masson - Stains Melanin BLACK
 Pearls Stain
 VonKossa stain
 Alizarin red stain
 Rhodanine stain
 Orcein stain
 The oil red O (ORO) stain can identify neutral lipids and fatty acids in smears and tissues. Fresh smears or cryostat sections of tissue are necessary because fixatives containing alcohols, or routine tissue processing with clearing, will remove lipids.
Q. Which of the following stains needs to be done on Frozen section and dont give optimum results in paraffin sections ?www.pgmeeuploads.com
Ans = Oil Red O [ See above]
CONNECTIVE TISSUE STAINS www.pgmeeuploads.com
 Masson trichrome stain - Collagen - Blue ( Following image shows section from liver showing nodule formation with bridging fibrosis - Collagen stained blue and liver parenchyma eosinophilic showing nodules enclosed by collagen) www.pgmeeuploads.com
Q. Which stain is used to demonstrate cirrhosis in liver ?www.pgmeeuploads.com
Ans = Masson trichrome > Reticulin Stain
 Reticulin stain - Reticulin fibres ( Type III collagen)
 van Gieson stain - Elastic fibres
GROSS STAIN = Amyloid initially stains deep brown with an iodine solution, but this turns blue after treatment with concentrated sulphuric acid.
 Congo Red = The binding arrangement between the dye and the amyloid produces a unique effect (apple-green birefringence) when the stained tissue is observed with polarized light. www.pgmeeuploads.com. The image below shows congo red stain of glomerulus with amyloid deposit which stains orange-red.
The glomerulus seen above when seen under polarised light show apple green birefringence ( See image below)
Lets look at another example of apple green birefringence in Muscle tissue - Amyloid deposit (See image below)
 Sirius red
 Wolman's Standard Toluidine Blue
Above three are viewed inder polarised microscopy.
There are also Fluorescent Amyloid Stains in which amyloid is fluorescent and do not require polarised light
 Thioflavine T & Thioflavine S - Fluorescent Amyloid Stains