[Histonet] formalin substitutes - tissue structure

[Yak-Nam Wang]

Dear Histonetters,

I have a question about alternatives to formalin fixation and fine changes
in tissue structure.

We have been obtaining formalin fixed human skin and fat samples from
several companies. We use stereological methods to make tissue measurements
such as dermal thickness and adipose cell size from sections stained with a
variety of basic stains. However,  there is now another company that we
would like to do obtain more tissue from but they can only provide tissue
fixed with a formalin alternative such as FineFix or Prefer. Measurement
data collected from formalin and formalin alternative fixed tissue would be
used together if we obtained tissue from this other company.

>From the Histonet archives I see that sometimes the use of formalin
alternatives can affect immuno staining, but does anyone know how it would
affect fine structure of tissue. My thoughts were that there may be a slight
difference in 'shrinkage' that occurs given the main ingredient is ethanol
on some of the alternatives, so fat fixed in one of these alternatives would
give an erroneously smaller adipose cell size. Any insight would be greatly
appreciated.

Thank you
Yak-Nam Wang

University of Washington