What are the differences between regressive and progressive staining?

Basis of differentiation 

Regressive staining

Progressive staining

Definition 

Is a type of staining in which the tissue is intentionally over-stained and then de-stained or differentiated until the it reaches the desired endpoint 

Is a type of staining in which the tissue is left in the staining solution just long enough to reach the desired endpoint 

Concentration of the stain

Highly concentrated

Less concentrated

Background stain 

Does not produce background staining

Produces background staining

Staining of non-cellular components

Stains non-cellular components

Does not stain non-cellular components

Coloring of the cytoplasm

Over-stains the cytoplasm

Cytoplasm is less stained

Differentiation step (excess stain removal) 

Contains a differentiation step

Does not contains a differentiation step

Differentiation in a dilute acid alcohol

Required 

Not required 

Use of eosin 

Uses eosin to stain non-cellular materials

Does not use eosin 

Haematoxylin concentration

Regressive haematoxylins are more concentrated

Progressive haematoxylins  are less concentrated

Commonly used stains

• Harris haematoxylin
• Ehrlich’s haematoxylin
• Delafield’s haematoxylin

• Gill’s haematoxylin
• Mayer’s haematoxylin

Speed of process

Is a fast process

Is a gradual process