Molecular and Cellular Radiobiology
Effects of Radiation and Chemicals on Control of
Hemopoiesis
RX-03-02-(b)
Project Title:
17.
Expected Resuits in FY 1974:
cells into erythropoiesis.
(Cont'd.)
Hypertransfusion of red cells in the intact
mouse suppresses input of HSC into erythropoiesis.
If the HSC flows
into the
erythropoietic pathway in the plethoric mouse after Fe-55 suicide continues,
it will prove the existence of the proposed intramedullary feedback loop.
In addition, a large number of mice will be treated with Fe-55 to induce
continued erythropoietic suicide in order to accelerate cell division at the
HSC level and to test the validity of Hayflick'’s hypothesis in the intact
animal,
It
is planned cto ascertain the D, of human HSC's in marrow from a
sufficient number of individuals to establish the statistical variation.
Attempts will continue to produce the diffusible factor that ,tnfluences
growth in the diffusion chambers by exposing goats to whole-body irradiation
followed by plasmaphoresis.
Activity will be sought first in the @,-glycoprotein fraction where CSF and EP are found.
Studies will also be performed
to see if extracorporeal irradiation of the blod
produce CSF, EP,
alone will suffice to
and the factor that stimulates growth of allogenic, autologous,
and xenogenic blood and bone marrow cells in diffusion chambers,
Studies on EP will continue with emphasis on determining the optimal
pCO9, p07, pH,
cultures,
and exogenous androgens on production of EP in glomerular
It is hoped to develop suspension cultures or large scale
monolayer cultures to produce large amounts of EP for purification, fraction- ‘
ation, and the production of antibodies against EP,
If the latter is
successful the anti-EP immunoglobulins will be separated; and using fluorescent
microscopy it is hoped to identify the EP-producing cell in the culture.
If :
large scale production of EP is successful, radioactive amino acids will be
added to the culture in order to produce radioactive EP for autoradiographic
studies of its cellular and subcellular localizations.
In collaboration with
Dr. Charles Saladino,
Adelphi University, the ultrastructure of the glomerular
cultures will be studied from time of preparation of the glomeruli and at
regular intervals after being placed into culture.
A microspectrophotometer must be obtained in order that systematic
studies on DNA content,
cell proliferation,
and tritiated thymidine labeling
of the normal and leukemic cells in culture may be continued as this phase
of the work can no longer be performed for us at the University of Copenhagen.
util
diffu
pts will again be made to produce large numbers of autologous HSC's
the system developed by Dr. Laissue to grow autologous cells in
chambers implanted in an animal's peritoneum, Marrow will be
fractionated to eliminate the differentiated cells,
The residual undifferentiated cells will be put into diffusion chambers and implanted into the
peritoneum of the mid-lethally irradiated goat and grown for the maximum
period of time before there is discernible cell differentiation.
At this
(See Continuation Sheet)
pt192491
RX- 231