>         I am having some difficulty overcoming background staining on
> formalin-fixed, paraffin-embedded, human lung tissue sections.  I have
tried blocking
> the tissues with chromotrope 2R, and with ammonium chloride.  Both of
these
> methods have not significantly reduced the amount of autofluorescence that
I
> observe.
>          Any advice that may be able to provide would be greatly
> appreciated.
> 
> Thank you for your time,
> Edie Hines
> Research Technologist
> Mayo Clinic Scottsdale
> hines.edith@mayo.edu
>