Lymph Node Prep
j.nelson at auckland.ac.nz
Fri Mar 22 12:00:18 EST 1996
We have been following the discussion about lymph node preps with
interest as we test a lot of FNAs although don't process whole nodes as
immunophenotyping is performed on sections by immunoenzyme analysis.
We usually receive FNAs on the day of collection so don't have a problem
with dead cells- collection into tissue culture medium rather than
saline or PBS helped to preserve the morphology of cells and allow them
to survive the Cytocentrifuge. We don't ficoll but if blood stained,
lyse the specimen (standard ammonium chloride method) as this also
produces better cytospins.
Obviuously the cell numbers vary enormously but if sufficient cells we
run through the flow but don't check viabiliity. We lyse first with a BD
formalin/water protocol and there is usually little debris and the CD45
gives us an idea about the quality of the cells.
For any neophyte FNA testers,the potential pitfall of analysing by flow
is ensuring that one is gating on the tumour population. Checking the
morphology of the cells is essential as sometimes the tumour cells are a
minority eg. 10%-20% with a background of T cells; therefore gating on
the lymphoid population produces spurious conclusions. If the tumour
cells can't be confidently identified in the flow graph we check the
lineage and for light chain restriction by APAAP immunoenzyme.
Department of Molecular Medicine
Auckland University School of Medicine
Private Bag, Auckland NZ
Phone: (+64)(9)373-7599 ext 6381
E-mail: j.nelson at auckland.ac.nz
More information about the Cytometry