title: Colony stimulating factor in human mixed leukocyte cultures.
abstract: Colony stimulating factor (CSF) is important for granulocyte/macrophage proliferation and differentiation. We investigated the relationship between the immune reactivity and the production of CSF by using two-way mixed leukocyte cultures (MLC) prepared from human peripheral mononuclear cells obtained with the aid of a blood cell separator. Assessed over 9 days of MLC incubation, the level of CSF in the supernatant reached a maximum at day 7 and then decreased. Optimal number of MLC cells ranged from 1 X 10(6)/ml to 2 X 10(6)/ml; CSF activity decreased at a cell concentration of 4 X 10(6)/ml. There was a differential sensitivity between cluster formation and colony formation to MLC-CSF. MLC-CSF is not species specific and hence, can stimulate both human and mouse CFU-c. MLC-conditioned medium (MLC-CM) appears to be a potentially useful source of CSF.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002452:Cell Count; D002469:Cell Separation; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D003470:Culture Media; D006801:Humans; D007700:Kinetics; D008214:Lymphocytes / Q000378:metabolism*; D051379:Mice; D009000:Monocytes / Q000378:metabolism*
chemical_list: D003115:Colony-Stimulating Factors; D003470:Culture Media