Re: blood cell chart and HSC total

[Guest guest]

Tracey and Marcos

From Tracey's note:

> Here is one of the sites that mentioned the 1 trillion turn over rate:

> http://www.lub.lu.se/luft/diss/med_853/med_853.pdf

The Introduction page has this statement.

Homeostasis, the maintenance of blood cells, is maintained throughout

life by a rare cell type residing primarily in the bone marrow (BM),

where it makes up less then 1 in 104 to 105 cells [1]. This cell type,

the hematopoietic stem cell (HSC), gives rise to all blood cell

progenitors through differentiation.

Using this ratio and the body's total blood cell count in the trillions

(10e12), this arrives at an estimate for the total HSC population in

the body of about 10 to 100 million cells.

I recall a graph I saw once that estimated the residual disease in a

CML patient in PCRU, which means only quiescent leukemic stem cells are

left, at somehwere around 10,000 to 1 million. I'll see if I can find

that figure. Dr. Tessa Holyoake's lab has done a lot of studies on the

leukemic stem cell. I'll see if she wrote on this subject

[Guest guest]

> I recall a graph I saw once that estimated the residual disease in

a

> CML patient in PCRU, which means only quiescent leukemic stem cells

are

> left, at somehwere around 10,000 to 1 million.

******************************************

Hi Tim,

I've aso heard those numbers tossed around to estimate the number of

cells involved in MRD. In fact, in the teleconference that I quoted

earlier (where Dr. Mauro said we have about a trillion leukemic cells

at diagnosis), he also hypothesized that we have between 100,000 and

a million leukemic cells left when we're PCRU.

http://tinyurl.com/28emoc

By the way, I'd like to thank you for such a wonderful and detailed

explanation on how FISH and Cytogenetics testing is performed. Your

knowledge and willingness to share with us is invaluable!

Tracey