H&E vs HPS

Unless you know histology, and even if you do, this title might be difficult to understand!

H&E; everybody knows. This is the standard staining procedure used in histology consisting of the nuclear stain hematoxylin and eosin counterstain. But what is HPS?
Here in the province of Quebec, many pathologists are influenced by the French tradition of staining with Hematoxylin, Phloxine and Safran. This staining method is similar to H&E while offering something more. The hematoxylin is the same, the phloxine replaces the eosin and the safran is the secret ingredient in this procedure. It stains collagen and conjonctive tissue orange, providing a clear delineation not obtained with eosin only.

In theory, eosin can provide different hues for the different tissue components but sometimes these differences are subtle. To the point that some manufacturers also offer an eosin-phloxine mix to provide a more reddish type brighter result.
Phloxine compared to Eosin provides more contrasted variations between the different structures stained. Adding safran gives the beautiful yellow-orange color to all collagen and connective tissue, which helps differentiate it from muscle and cytoplasm that are stained pink. This allows for the detection of illnesses such as fibrosis that could go undetected by H&E.

Safran is readily available in Europe and it is good to know that Chaptec offers it to its North American customers, enabling the maintaining of this rich tradition!