Publicidad
Methodology Guidelines
Specimen Dilution
Cytology specimens often are submitted to the laboratory
with a cell concentration that is too high for Cytospin
preparations until diluted. Such specimens are common
from bone marrow, lymphoid aspirates, and many fine
needle aspirates. These concentrated specimens should first
be evaluated for cell number, using any of the previously
described techniques. The specimen should then be diluted
to an approximate cell concentration by addition of a
balanced electrolyte solution. It is important to use a fluid
that has a proper osmolarity, in order not to introduce
structural changes in the cell sample. Simple solutions of
Sodium Chloride (0.9% saline) are unsuitable as diluents
- they produce rapid changes in nuclear chromatin and
interfere with subsequent cytological evaluation.
Many of the solutions commonly used in tissue culture
laboratories are suitable diluents, such as Earle's balanced
salt solution, or Hank's balanced salt solution. In many
cases, if the cell suspension submitted to the laboratory has
been collected in one of these diluents, or has undergone
significant processing in such salt solutions, it may be
advisable to add some protein to the diluent. Either human
serum or a solution of bovine serum albumin may be
used. The usual concentration of these solutions is 1 to 30
percent. The protein solutions of very high concentration are
usually used by dropwise addition to the sample just prior to
or during loading of the Cytospin funnels.
Loading the
The sample chambers hold a maximum of 0.5 ml of
specimen and should hold no less than 0.1 ml. Do not place
Cytospin Sample
more than 0.5 ml of sample in each standard EZ Cytofunnel
Chambers
sample chamber (up to 6ml for EZ Megafunnels).
Additional sample would simply be thrown to the top of
the chamber during Cytospin operation, and could not be
deposited on the slide. It is recommended that the sample
chambers are loaded after they have been assembled and
inserted into the sealed head. The design of the chamber
assemblies and the sealed head ensures that the sample
chambers tilt in such a manner that the specimen will
not contact the slide or the filter card prior to starting the
Cytospin. The specimen must never contact the slide or
filter before the Cytospin is started. The operator must be
A78310250ES 5.1ª Edición
Manual de operaciones de la Cytospin 4
95
Publicidad
