Massachusetts General Hospital



Medical Director: Aliyah Sohani, M.D. 617-726-2967
Technical Director: Denise Bland 617-726-5153
Supervisor: William Anim 617-643-6236

Lab Hours

Monday-Friday: 12:00 AM to 10:30 PM
Saturday-Sunday: 8:00 AM to 4:30 PM


The Histology laboratory for the MGH Pathology Service is a full service routine histology laboratory and a complete pathology and histologic interpretation laboratory. We provide paraffin and frozen histology services. Please see our IHC/SPU Laboratory information for advanced special techniques. Founded in 1896, our department was one of the first of its kind in the United States. We welcome enquires and we enjoy sharing our techniques with other laboratory professionals. Please see our previously listed contact information. We prepare tissue samples for both clinical and research purposes, gross through H&E. If you would like to contact us for research services you must be working with one of our pathologists. Cost and turnaround time are amenable to the before mentioned conditions.

Hematoxylin is the oxidized product of the logwood tree known as hematein. Since this tree is very rare nowadays, most hematein is of the synthetic variety. In order to use it as a stain it must be “ripened” or oxidized. This can be done naturally by putting the hematein solution on the shelf and waiting several months, or by buying commercially ripened hematoxylin or by putting ripening agents in the hematein solution.

Hematoxylin will not directly stain tissues, but needs a “mordant” or link to the tissues. This is provided by a metal cation such as iron, aluminum, or tungsten. The variety of hematoxylins available for use is based partially on choice of metal ion used. They vary in intensity or hue. Hematoxylin, being a basic dye, has an affinity for the nucleic acids of the cell nucleus.

Hematoxylin stains are either “regressive” or “progressive”. With a regressive stain, the slides are left in the solution for a set period of time and then taken back through a solution such as acid-alcohol that removes part of the stain. This method works best for large batches of slides to be stained and is more predictable on a day-to-day basis. With a progressive stain the slide is dipped in the hematoxylin until the desired intensity of staining is achieved, such as with a frozen section. This is simple for a single slide, but lends itself poorly to batch processing.

Eosin is an acidic dye with an affinity for cytoplasmic components of the cell. There are a variety of eosins that can be synthesized for use, varying in their hue, but they all work about the same. Eosin is much more forgiving than hematoxylin and is less of a problem in the lab. About the only problem you will see is over staining, especially with decalcified tissues.

Histology: Full service from fixation to staining.

We provide:


  • Complete services for routine tissue processing, embedding and sectioning.
  • H&E staining and production of unstained slides.
  • Consultation and advice for all histology and pathology enquiries.
  • Interpretation of final sections after all types of staining.


Our tissue processing and all histology procedures are designed to:


  • Optimize tissue fixation
  • Optimize preservation of antigens and cellular detail
  • Orient tissue for sectioning to achieve structure for analysis. Routine clinical tests have an expected turn-around time of 4hrs to 24hrs, exceptions being rush cases and those which require additional processing. Research tests are given a maximum TAT of 14 working days.