Megakaryocyte colony-stimulating factor and burst-promoting activity in LPS-treated mouse spleen cell-conditioned medium.
In order to clarify the mechanism(s) of increased splenic hematopoiesis noted in lipopolysaccharide (LPS)-injected mice, the effects of spleen cell-conditioned medium (SPCM) on megakaryocyte colony (CFU-meg) formation and early erythroid (BFU-e) differentiation were investigated. After spleen cells from LPS-injected mice were incubated for 3 days, the SPCM was assayed for megakaryocyte colony-stimulating factor (Meg-CSF) in CFU-meg assay and for burst-promoting activity (BPA) and erythropoietin (Epo) in erythroid colony assays (i.e., CFU-e, BFU-e). Colony formation of CFU-meg and BFU-e peaked with the addition of 30 and 10-15% SPCM, respectively. Spleen cells from LPS-injected mice produced Meg-CSF and BPA when compared with controls. However, conditioned medium from spleen cells depleted of phagocytic cells had low Meg-CSF and BPA. SPCM did not contain detectable quantities of Epo. It appears likely that local splenic production of Meg-CSF and BPA may affect proliferation of CFU-meg and erythroid progenitor cells in the spleen.
Sugimoto
M
M
Hipple Cancer Research Center, Dayton, Ohio.
Wakabayashi
Y
Y
Hirose
S
S
Murphy
M J
MJ
D000818:Animals; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D003470:Culture Media; D004920:Erythropoiesis / Q000187:drug effects; D058851:GPI-Linked Proteins; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008222:Lymphokines / Q000037:antagonists & inhibitors*; D008297:Male; D008562:Membrane Glycoproteins; D000090204:Mesothelin; D051379:Mice; D008811:Mice, Inbred DBA; D014176:Protein Biosynthesis; D011506:Proteins; D013154:Spleen / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D019714:Tissue Inhibitor of Metalloproteinases
D003115:Colony-Stimulating Factors; D003470:Culture Media; D058851:GPI-Linked Proteins; D008070:Lipopolysaccharides; D008222:Lymphokines; D008562:Membrane Glycoproteins; D011506:Proteins; D019714:Tissue Inhibitor of Metalloproteinases; D000090204:Mesothelin