Special stains and IHC Flashcards
Which stain can be used to assess the basement membrane?
Periodic acid Schiff
Ziehl-Neelson staining can detect mycobacteria and which other weakly acid fast organisms?
Rhodococcus equi and Nocardia Spp
Which part of a fungus does Grocott’s Methenamine Silver (GMS) specifically stain?
Polysaccharide components of the fungal cell wall
What does Mayer’s Mucicarmine stain?
Polysaccharides on the capsule of Cryptococcus neoformans and mucins.
What is Gomori’s One-Step Trichrome stain used for?
For distinguishing collagen and smooth muscle fibers
What is Masson’s Trichrome stain used for?
Used for distinguishing cells from surrounding connective tissue which has several variants and is probably the trichrome most used in histopathology. Black nuclei, red cytoplasm (including muscle), blue or green collagen (including fine fibers), cartilage and mucus
What is Russel-Movat Pentachrome stain used for?
Used for simultaneous demonstration of muscle, elastic fibers, collagen/reticular fibers, ground substance and fibrinoid in tissues
What are Oil Red O and Sudan Black B stains used for?
Used for staining lipids in frozen sections and some lipoproteins on paraffin sections.
Lipids, including triglycerides (which necessarily are neutral). Oil Red O stains only the most hydrophobic lipids (triglycerides and cholesterol esters). Sudan Black B stains these and also phospholipids and sphingomyelins, which are less hydrophobic
What is Orcein stain used for?
Used for staining elastic fibers
What is Lendrum’s Method (Picro-Mallory Stain) used for?
For staining fibrin
What does Congo Red stain show?
Amyloid deposits
What is Masson-Fontana stain used for?
Used for the detection of melanin
What is Alcian Blue stain used for?
Used in identifying mucins and glycosaminoglycans e.g. hyaluronic acid
Which inflammatory cell stains with Giemsa Stain?
Mast cells
What are the Brown-Hopps and Brown-Brenn stains?
Modifications of the Gram stain and are used for demonstration of Gram-negative bacteria and rickettsia
Which special stain can be used to identify Leishmania?
Giemsa
What type of molecule does PAS stain?
Mucopolysaccharides, especially glycogen
What does Verhoff von Gieson stain?
It is a silver stain used to demonstrate and evaluate the quantity and quality of tissue elastic fibers. Positive staining is perceived as black.
What colour do Mycobacteria stain with Ziehl-Neelson?
Red
Smooth muscle and keratin stain pink-red, collagen stains blue-green, and elastic fibers appear black with which special stain?
Masson’s Trichrome
How do you differentiate Langerhans from dermal dendritic cells? Both stain for IBA1 on IHC
Langerhans cells are CD204 -ve and E-cadherin +ve
Dermal dendritic cells show variable CD204 staining and are E-cadherin -ve
Which cells are CD3 +ve?
T cells
Which cells are CD20 +ve?
B cells (some cross over reported with neoplastic T cells in epitheliotropic lymphoma)
Which cells stain with CD79a?
B cells
Which cells are vimentin +ve?
Vimentin is present in cells of mesenchymal origin and in mesenchymal derived tumours such as lymphomas, sarcomas and melanomas
IHC to detect CD18 and MHC class II was equally effective in staining histiocytomas, although lymphosarcoma must be ruled out through the use of ____ and ____ IHC
CD3 and CD79a
Which markers can be used for IHC to identify melanomas?
Melan-A, PNL-2, TRP-1 (tyrosine related protein), and TRP-2
Pancytokeratin is an IHC marker for which type of cells?
Epithelial cells
In pagetoid reticulosis, are T cells alpha-beta or gamma-delta positive?
All are gamma-delta positive
Which IHC stains can be used to identify B cells?
CD79a, CD20, Pax5
Name two neural crest cell markers
S-100 and neuron specific enolase (NSE)
What can you use to help assess cell morphology in highly pigmented melanocytes?
Bleach
Name three prognostic IHC markers for melanomas
- FoxP3 and IDO
- MCAM/CD146
- C-kit receptor
- Nuclear survivin
- COX-2
- Ki67
Name four plasma cell markers
CD79a CD20 CD18 Immunoglobulin kappa light chains MUM1/IRF4
Other than plasmacytomas, which other tumour can be positive for MUM1/IRF4?
Histiocytoma
Histiocytoma in dogs stains with which markers?
CD1a
CD11c/CD18
E-cadherin (specific to Langerhans cells)
Iba1
Iba1 is marker for which cell lineage?
Monocyte/macrophage lineage cells in dogs and cats
How many mitotic figures PHPF are in grade 1, grade 2 and grade 3 (Patnaik) MCTs?
Grade 1 = 0
Grade 2 = 0-2
Grade 3 = 3-6
How many mitoses PHPF are in low and high grade (Kiupel) MCTs?
Low = <7 in 10 HPF High = at least 7 in 10 HPF
What IHC markers can be used for MCTs?
Mast cell tryptase
CD117/c-kit
Which cytokeratins can help distinguish SCC from basosquamous variants in dogs?
Cytokeratin 6 and 10
Weibel-Palade bodies are specific markers for which cells?
Endothelial cells
Cytokeratin positive; CK7/8 (CAM 5.2) and CK13 are relatively specific markers for which type of epithelia?
Glandular
Name macrophage IHC markers
CD68
MAC 387
Lysozyme
