In vitro effects of OK-432 on irradiated mouse bone marrow cells.
OBJECTIVE
In vitro effects of OK-432 on irradiated mouse bone marrow cells are examined.


METHODS
Bone marrow cells of BDF1 mouse (1 x 10(6) cells/ml) were incubated with alpha medium, 2% fetal calf serum and OK-432 in a CO2 incubator at 37 degrees C for 24, 48 and 72 h, respectively. After centrifugation, each supernatant was collected and used for conditioned medium in CFU-GM assay: Changes in CFU-GM as a function of incubation time and OK-432 dose was examined; changes of CFU-GM according to various doses of OK-432 were examined in two mouse strains, BDF1 and BALB/c mouse; changes in protective effect of OK-432 in terms of CFU-GM as a function of administration timing of OK-432 in relation to irradiation. As a radiation source, 137Cs at a dose rate of 500 cGy/min was used.


RESULTS
The CFU-GM decreased with the incubation time when OK-432 was not administered, while it significantly increased with incubation time when OK-432 was added at 0.5 and 1.0 KE/ml at 48-72 h of incubation. The former showed marked increase at 48-72 h of incubation. CFU-GM of BDF1 mouse was always higher than that of BALB/c mouse for any dose of OK-432. CFU-GM per femur according to the timing of administration of OK-432 from 24 h before to 24 h after irradiation showed 10299 +/- 2300 (24 h before), 10783 +/- 2463 (3 h before), 10045 +/- 1501 (immediately after), 8504 +/- 1188 (3 h after), 4898 +/- 1212 (6 h after), 1214 +/- 736 (12 h after) and 181 +/- 113 (24 h after irradiation), respectively.


CONCLUSIONS
OK-432 stimulates cultured mouse bone marrow cells to produce GM-CSF in vitro by direct contact action. This direct stimulating action of OK-432 on GM-CSF production of bone marrow cells can be kept from 24 h before to at least 3 h after irradiation.
Nose
M
M
Division of Radiation Health, National Institute of Radiological Sciences, Chiba, Japan.
Aoki
Y
Y
Kawase
Y
Y
Suzuki
G
G
Akashi
M
M
Akanuma
A
A
D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000528:radiation effects*; D002478:Cells, Cultured; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000528:radiation effects; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010844:Picibanil / Q000494:pharmacology*; D011837:Radiation-Protective Agents / Q000494:pharmacology*
D011837:Radiation-Protective Agents; D010844:Picibanil; D016178:Granulocyte-Macrophage Colony-Stimulating Factor