Linda Sebree's quotation from her pathologist "the antibody ain't
dead" was great ---even if stupid!  (Not you Linda).

Unless aspirated or "exfoliated", or scraped cells are placed
immediately into liquid fixative they are going to be very
significantly different to immersion fixed tissue in their micro-
structure.   They will immediately start to dry.  Most likely they will
also stretch because they will stick to the glass.

You have to use your imagination on how they can stick and
stretch at the same time - I don't know how to explain that without
using my hands and a piece of chalk!

The consequence is that the cytoplasm will become more "dense"
and the cell therefore less accessible to staining molecules.
Antibodies being the "staining molecules" in ICC and they are BIG.
 Boy, are they big.

So the only possible sites they can find to bind to are those on the
surface and that is relatively few.  And they are the cells most
affected by the drying.

If cells really can be "wet fixed", as all the text-books recommend
for these purposes, so much the better.  But as soon as a cell
suspension touches the slide, it starts to dry.

If they ain't dead enough, it's 'cos they were too dead to start with!

Antibodies ain't dead when assayed in ELISA or latex tests for
glandular fever, etc., etc.
Russ Allison,
Dental School
Cardiff
Wales