B cell precursors

Pilar Calo calomata at facstaff.wisc.edu
Thu Aug 21 12:03:55 EST 1997




Wal,
 according to our experience in the FlowCytometry Group of BIOMED Concerted
Action for Minimal Residual Disease there are three major B-cell (CD19+)
populations (=maturational stages) in the normal bone marrow differing in
expression of CD10, CD22, CD45 and CD20:

1. CD10 bright/CD22dim/CD45 dim/CD20 neg
2.CD 10 pos./CD22dim/CD45dim-pos/CD20dim
3.CD10neg/CD22bright/CD45bright/CD20 bright.

The population you describe does not fit in any of the above, unless the
antibody played up and you deal with the population 2....
Best wishes
Anna

Anna Porwit-MacDonald MD, PhD
Haematopathology Lab,
Karolinska Hospital, Stockholm

>
>A question to the those on the list with experience in early B cells in
>normal bone marrow:-
>
>Would you expect SURFACE CD22 to appear before CD20 in normal B cell
>development ?
>
>The reason I ask is we had a BM specimen in the other day in which we found
>a population of CD19+/10+/20+/22neg/45dim cells which is a phenotype we
>have seen on some of our NHL's with marrow involvement (& of course 22 is
>neg on most of our CLL's).
>I ran out of specimen before I could do any more CD's.
>The percentage of these cells is too low to give a definitive diagnosis and
>I don't want to mix up lymphoma cells with normal precursors.
>Sorry for such a basic question but I deal almost exclusively with ALL's
>where CD22 almost invariably appears before CD20 on the surface - at least
>with our leuks, which tend to be different from "western" types
>We have asked them (another hospital) to send us a suspension from a node
>biopsy.
>
>
>Thanks
>
>Wal Sharp
>SQU
>Oman (for the time being!)
>
>
>





More information about the Cytometry mailing list