On Mon, 13 Sep 1999, A G DU TOIT wrote:

> I am looking for a stain specifically for Mast cells.  We have been 
> doing the Bismarck Brown for some time, but unfortunately no 
> literature available.  Surely somebody might just be able to help.
> Thanks a million in advance, I am looking forward to hear from all of 

  The easiest way to stain all mast cells (also cartilage matrix
  and some goblet cells) is with a basic dye at pH 1. Alcian
  blue is often used. Toluidine blue is a stronger colour (red to
  purple because of metachromasia).

  The basic (cationic) dyes bind to the sulphate (strong acid)
  groups of heparin, which is the defining component of the
  mast cell granule. At low pH the weak acids of most other 
  basophilic objects, including nuclei, are not ionized so
  they cannot attract the dye cations. 

 John A. Kiernan,
 Department of Anatomy & Cell Biology,
 The University of Western Ontario,
 LONDON,  Canada  N6A 5C1