CyTOForum

Need some bone marrow peeps opinion,

First time working on bone marrow
I am running healthy donor bm on cytof and have, using different donors and different panels (for now PBMC tailored panels unfortunately so not many bm markers), observed double CD45 pop. See the screenshot, gaussian cleaned singlets as pre-gating to this, doublets excluded.
Its also CD66b neg.
Is this to be expected?

yes this is quite common. I have not analyzed them separately TBH and always assumed these were less mature populations since this is BM.

Generally CD45 will progressively increase on cells as they differentiate away from the stem cells and into mature leukocytes (and progressively downregulate for erythrocytes etc). Final CD45 levels on depends on the lineage (e.g. low on neutrophils, high on lymphocytes etc).

You should see _some_ CD66b+ cells in that CD45low fraction, as CD66b comes up quite early on bone marrow neutrophils.