Question

How to prepare the liver tissue for H&E staining and special staining? write an essay. The steps must included must focus on preparing the liver tissue for staining and should not be written in a general context. Please be precise on the types of reagents and stains that will be used in each step.

Answer 1

H&E stain or HE stain is one of the principal tissue stains used in histology.It is the most widely used stain in medical diagnosis and is often the gold standard.For example, when a pathologist looks at a biopsy of a suspected cancer, the histological section is likely to be stained with H&E.

The results from H&E staining are not overly dependent on the chemical used to fix the tissue or slight inconsistencies in laboratory protocol.

H&E staining does not always provide enough contrast to differentiate all tissues, cellular structures, or the distribution of chemical substances, and in these cases more specific stains and methods are used.

Method of preparation

There are many ways to prepare the hematoxylin solutions (formulation) used in the H&E procedure.some of which may be specific to a certain laboratory. there is no standard procedure, The results by convention are reasonably consistent in that cell nuclei are stained blue and the cytoplasm and extracellular matrix are stained pink. Histology laboratories may also adjust the amount or type of staining for a particular pathologist.

[ ] Steps

1 tissues have been collected (often as biopsies) and fixed, they are typically dehydrated and embedded in melted paraffin wax, the resulting block is mounted on a microtome and cut into thin slices.

2 The slices are affixed to microscope slides at which point the wax is removed with a solvent and the tissue slices attached to the slides are rehydrated and are ready for staining.

3 Alternatively, H&E stain is the most used stain in Mohs surgery in which tissues are typically frozen, cut on a cryostat (a microtome that cuts frozen tissue), fixed in alcohol, and then stained.

4 The H&E staining method involves application of haematoxylin mixed with a metallic salt, or mordant, often followed by a rinse in a weak acid solution to remove excess staining (differentiation), followed by bluing in mildly alkaline water.

5 After the application of haematoxylin, the tissue is counterstained with eosin (most commonly eosin Y)