> I was asked if there is a method to detect stem cells, either 
> by histologic
> or immunostain? I have never stained stem cells. Does anyone 
> have a method
> for stem cell staining?

It depends what's a stem cell to you ;-)

In routine pathology, staining with an antibody to CD34 (clone Q-BEND10) is
routinely used for this purpose. In normal bone marrow, about 1-2 % of small
lymphocytoid cells are stained. Note that CD34 also stains a lot of other
cells (endothelium, some soft-tissue tumors, etc.) and sometimes
megakaryocytes (especially in hypercellular MDS) too. But do not rely on
immunohistochemistry if you need to count stem cells: for an unknown (at
least to me) reason, in haematological malignancies the immunhostochemical
count and the results of flow cytometry are quite different in most of the
cases.

Alex Nader