Dear Carrie,
     When I worked in research, we sometimes had very tiny conglomerations of 
cells or extremely small samples to process.  There is a commercially 
available product for these situations called HistoGel.  You can heat the 
HistoGel to 60 degrees C, and drop the liquefied HistoGel onto your samples.  
Once the HistoGel cools to about 20 degrees C, it becomes a clearish rubbery 
substance containing your specimen that is permeable to processing reagents 
and can be run on the processor with your other samples.  Then, you can 
paraffin embed the HistoGel with your cells in it, as you would a tissue 
sample, and section it.  Fisher carries HistoGel and it is catalog 
#22-045381.  Another possible option is to put the cells on or between 
membrane(s) or thin biopsy wraps and embed and section the whole 
cell-and-wrap "sandwich."

Good luck!

Kimberly Atkin HT (ASCP)

Histology Laboratory Supervisor
Angell Memorial Animal Hospital
350 South Huntington Avenue
Boston, MA 02130

Paraffin Block preparation from Cultured Cells
From: Carrie Eberhardt <carrie.eberhardt@impath.com> 

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Hello!  I am attempting to make paraffin blocks of cultured cells and our
pathologist has noted that the cell density is not good enough, so I am
asking for tips/ protocols that anyone may be using.

I start with at least 6 million cells, pellet them in a 15 ml centrifuge
tube, pour off media and add a couple drops of warm 3% Eosin/Agar and vortex
to mix.  The cells are immediately chilled on ice and the agar cell pellet
is fixed in Formalin and processed on a short cycle on an automated
processor.  At this time, we embed the entire processed pellet, but we are
trying to core a paraffin block and insert a cored agar pellet with no
avail.

Any tips out there?

Carrie 
IMPATH-LA