In article <47m6rd$8bs at newsbf02.news.aol.com>,
alussow at aol.com (ALussow) wrote:
>Can anyone tell me how many CD4 or CD8 molecules there
are on the
>corresponding murine or human T-cell?? What is the
surface area of the
>cell??
>>Thanks
>Alex
>If you don't ask much from life, that's what you'll get.
An interesting and difficult question. Also a relatively
useless
one as far as clinical applications.
At this time I can only propose to work around an answer.
The
cell diameter range that T cells far into is 9-12 microns.
Other
cells, such as immature basophils, also fall into this
range. If
one wants to assume a sphere that you can calculate from
the
diameter. Electronic cell counters measure volumne in
femtoliters. This is true with RBCs. I seem to remember
seeing
somewhere that T cell volume is between 140 and 160
femtoliters
(but need shape to calculate surface area), but I have no
reference to support this. Just to be sure that we are on
the
same page, I want memtion that one cannot classify a cell
soley
volume. Electronically derived WBC differentiatials use
volume
as part of the classification. The volume used however
seems to
be found in the manufacture's software algrithm. Such
algrithms
are appearently company secrets.
As to the number of CD4 & CD8 receptors this would vary
with cell
maturity and possibly with TCRs. As TCRs are continuously
replaced so might CD4 & CD8. I do not think that anyone
knows
the answer to your question. I would like to guess that
it is in
the hundreds. Someone out there correct me!
