Could it be blood smears, done in the classical way on Plus Charge slides
do not like the positive surface?  I recall having to do blood smears on
very clean regular glass slides in order to just get a good smear - old med
tech days!    

Cytospin might put the cells into better contact against positive surface.
You may have to resuspend/dilute blood cells in a buffer, then spin.  One
student did this with white blood cells (PMN's), but did not do ISH.  Her
cells did not fall off slide after cytospins.

 
Gayle Callis
MT,HT,HTL(ASCP)
Histopathology Supervisor
Veterinary Molecular Biology
Montana State University - Bozeman
Bozeman MT 59717-3610