Maryalice
We have just begun a pilot study with TPO in breast-Ca and are currently using
a three color panel of CD41FITC(BD), CD90PE(PharMingen) and CD34PerCP(BD) to
define the mega. The major problem is to be sure that you are not identifying
platelets attached to cells. I would recommed the use of ACD-A as an
anticoagulant to reduce the 'platelet stickiness'; and you might want to
include CD62 for activated platelets and a marker to ensure that the CD41+
are not attached to monocytes or granulocytes. We are using a 50,000 event
live gate in the lowSSC and the majority of the CD41+CD34+THYdim cells are in a
region just above the lymphocytes and in our normal GCSF stimulated donors this
represents approx 0.06% total cells.
Maryalice Stetler-Stevenson
Director Flow Cytometry Unit
Laboratory of Pathology, NCI, NIH