title: Rabbit bone marrow suppressor cells block the production or release of a soluble bone marrow growth factor.
abstract: Fc gamma-receptor (Fc gamma R)-bearing cells from normal rabbit bone marrow suppressed the constitutive proliferation rates of the remaining, Fc gamma R-, cells. In the absence of the suppressive influences of Fc gamma R+ cells, cells in the Fc gamma R- population spontaneously elaborated a soluble growth factor (GF) which induced the proliferation of unseparated bone marrow cells. To examine regulation by Fc gamma R+ bone marrow cells, graded numbers of the Fc gamma R+ cells were mixed with constant numbers of the FcR- cells. At 24 hr, supernates were collected and tested for GF activity. The Fc gamma R+ suppressor cells efficiently and in a dose-dependent fashion blocked GF production or release. The GF was nondialyzable and relatively heat stable. Supernates with GF activity also had colony-stimulating factor activity, but were negative in assays modified from murine interleukin 1 (IL-1) and IL-2 assays. Regulation of GF production or release represents a new function for bone marrow suppressor cells.
authors.forename: L S
authors.initials: LS
authors.lastname: Soderberg
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D003115:Colony-Stimulating Factors / Q000032:analysis; D003470:Culture Media; D006133:Growth Substances / Q000096:biosynthesis*; D006358:Hot Temperature; D007375:Interleukin-1 / Q000032:analysis; D007376:Interleukin-2 / Q000032:analysis; D011817:Rabbits; D011961:Receptors, Fc / Q000032:analysis; D050378:T-Lymphocytes, Regulatory / Q000502:physiology*
chemical_list: D003115:Colony-Stimulating Factors; D003470:Culture Media; D006133:Growth Substances; D007375:Interleukin-1; D007376:Interleukin-2; D011961:Receptors, Fc