Hi, Pat,
         You asked:



         Well... I am in the process of embedding and sectioning a 
multi-layer tissue culture grown in a petri dish.  However, I'm not using 
paraffin.  I'm using glycol methacrylate (Technovit 7100).  I process the 
plate through the VIP tissue processor up to the xylenes, remove and place 
in increasing strengths of  glycol and then embed in GMA, allow to 
polymerize and section on the Polycut E.  So far...so good!  We tried this 
on a blank petri dish and it worked just fine.
         Your petri dish will not cut with paraffin embedding. For you to 
do paraffin, you will need to remove the cells from the petri dish by 
trypsinizing them and then centrifuge the solution, decant the supernatant, 
process the cell button and hope for the best. Just a thought...you might 
try processing the petri dish without the cells (pilot study) through the 
processor and fill the petri dish (if it hasn't dissolved or distorted due 
to the xylenes) with wax, allow to chill and pop it out of the petri dish 
and see if the cells (use a substitute if you have limited cultures) attach 
to the surface of the wax instead of remaining on the petri dish.  Then you 
could re-embed the trimmed paraffin circle into a metal 
basemold.  Remember, you are dealing with cells, not "hunks" of tissue.
         Also, you can stain the cell in the dish with toluidine  blue if 
you just want a "quick and dirty" stain for viewing microscopically.
         If you want my exact processing schedule for GMA, I will be glad 
to send it to you.
         Best wishes,
         Linda



Linda Jenkins, HT
Clemson University
Dept. of Bioengineering
Clemson, SC 29634-0905
864.656.5553