[Histonet] Using acetic acid alone as a fixative

[gayle callis]

Dear Histonetters, 

 

I have a person using acetic acid as a fixative for frozen sections
containing bioluminescent proteins (GFP and tdTomato, a red fluorescent
protein). 

 

I have always been taught to use acetic acid in combination with other
chemical agents (e.g. as in Bouins  or Carnoys) but not alone due to the
swelling of cells and tissues and probably other acid protein hydrolysis
going on too.   

 

Has anyone ever run across using acetic acid (concentration is not high, but
not known by me)?  She does encounter problems with GFP staining, but the
tdTomato still glows although her results are inconsistent.  

 

I have no clue where this fixation method originated from but I suspect it
may be from a fixative where something was lost in making it
up/forgotten/left out - ending up with acetic acid alone.  A quick look in
Sheehan and Hrapchak's  Theory and Practice of HIstotechnology, indicated
acetic acid was rarely used alone for fixation.  I am off to John Kiernan's
book after sending this message.   

 

I understand the sensitivity of GFP and some other GFP chimeras , also RFP
(closely related structurally to GFP) to alcohols and other organic
solvents, heat, and pH where fluorescence is lost and/or diminished
significantly.  

 

Enlighten me please

 

Gayle M. Callis 

HTL/HT/MT(ASCP)