ISSN:
0275-3723
Keywords:
erythropoietin
;
macrophages
;
silica
;
erythrocytic colony-forming units
;
polycythemic mouse bioassay
;
anti-erythropoietin
;
Chemistry
;
Molecular Cell Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
An erythropoietic stimulating factor (ESF) can be shown to be released from preincubated macrophage-containing cell suspensions from mice by the macrophage-specific, cytotoxic agent, silica. A concentrated silica treated spleen cell supernatant containing ESF is shown to cause a dose dependent increase in 59 Fe incorporation into red blood cells using the in vivo polycythemic mouse bioassay. The ESF from the same supernatant can also be neutralized by anti-erythropoietin. A second concentrated supernatant fractionated using wheat germ lectin-Sepharose 6MB and compared to either unfractionated or fractionated step 111 erythropoietin (Ep), tested in vitro using the erythroid colony-forming technique and 12-day fetal liver as target cells, indicates parallelism of all linear dose-response lines. This, together with the in vivo data, strongly suggests that the ESF released from macrophages treated with silica is, in fact, Ep. Substituting Ca2+ ions for fetal calf serum in the preincubation procedure results in the same activity being released compared to the presence of 1% or 20% fetal calf serum.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jsscb.1981.380150208
