David

I have seen cytoplasmic staining at times with a polyclonal p53 antibody.  I
can't speak for the monoclonals as at that time they were all human specific
and I was working with mice and rats.  It was theorized that the p53 was
binding to Heat Shock 
Protien (HSP).   We did not count these cells as positive.   I have also
seen cytoplasmic staining with PCNA mostly in liver, rat, mouse and trout
but (so far) not in human liver biopsies.  Again, if there was no nuclear
staining they were not counted.  If there was then they were counted.

Remedy,  it doesn't happen often enough (in our lab.) to be a concern.  I
suspect that this may be 'real' staining and that some of these antigens may
be binding to a cytoplasmic protien, possibly to HSP.  It would be
interesting to see if this was the case using a double labeling method.
Unfortunatly I haven't the time latly.

-- Begin original message --
> 
> Dear Histonetters,
> 
> Has any one ever seen P53 staining with cytoplasmic staining only?   Is
> there any remedy?  Also has anyone ever seen Ki-67 (MIB-1 or other Ki-67
> monoclonal antibodies) with both cytoplasmic and nuclear staining?  Is
> there a remedy?
> 
> Dave
> 
> 
> 

-- End original message --

best regards,
Bob
Robert Schoonhoven
Laboratory of Molecular Carcinogenesis and Mutagenesis
Dept. of Environmental Sciences and Engineering
University of North Carolina
CB#7400
Chapel Hill, NC 27599
Phone 
office 919-966-6343
   Lab 919-966-6140
   Fax 919-966-6123 

Don't go around saying the world owes you a living; the world owes you
nothing; it was here first. 
Mark Twain [Samuel Langhornne Clemens] (1835-1910)