I posted a question about the lymphocyte subset problem
after CD34 selection. Now, I'll tell you more about it.
1. Dr. Timothy Farley asked me about the absolute number
and the proportion of CD34 positive cells.
-> First day
PBPC collection bag : 1233/uL (0.92%)
Post CD34 selection : 1172/uL (35.0%)
Second day
PBPC collection bag : 962/uL (0.45%)
Post CD34 selection : 550/uL (45.0%)
2. Dr. Dennis told to me that anti-CD19 antibody might stick
to CD34 positive cells and their fluorescence also might
be dim. He said in his experience that bright CD19 (true)
cells are about 1%.
-> Our results showed that CD19 fluorescence was as bright
as other fluorescences such as CD3 and CD19 positive
populations were identified without difficulty.
3. Dr. Donnenberg said that CD3+/CD19+ cells could be T cell/
B cell conjugates.
-> I can't imagine all CD3+ and CD3- cells might conjugate
with CD19+ B c
ells.
4. I tested the possibility that some procedure could make
all cells change their unknown surface antigen and then
they got the power to bind anti-CD19 antibody.
-> I tried to simulate all procedure such as wash, incubation,
and so on for the selection of CD34 positive cells without
anti-CD34 monoclonal antibody and passing through the column
which captures the CD34 positive cells.
Unfortunately, the lymphocyte subset was normal.
Now, I have no way to solve the problem other than waiting
another PBPC and CD34 selection.
Is there anyone who can give me a hint?
Thanks a lot.
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Chang-Seok Ki, MD
Dept. of Clinical Pathology
Samsung Medical Center
Seoul, Korea
Voice (82)-2-3410-2708
Fax (82)-2-3410-2719
E-mail kcdol@samsung.co.kr
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