title: Initial description of a tumor enhancing activity produced by murine splenocytes.
abstract: We have shown that certain murine tumors grow more slowly and spread less readily in immune deficient animals. We have also demonstrated that immunologic factors explain certain aspects of this difference. In the work presented we demonstrate that a subpopulation of splenocytes produce a factor(s) that enhances tumor cell proliferation in vitro. We also describe an in vitro model to determine the level of tumor stimulatory activity. We found that the tumor cell growth-enhancing activity (TEA) is heat stable but sensitive to trypsin digestion, low pH and beta-mercaptoethanol. TEA production is found to be insensitive to mitogen stimulation such as concanavalin A, lipopolysaccharide, and phytohemagglutinin. Among the known growth factors and interleukins we have tested (interleukin 1-7, basic FGF, EGF, TGF-beta PDGF, GM-CSF, and MCSF), none appear to account for TEA activity.
authors.affiliation: Department of Medicine, University of Wisconsin-Madison.
authors.forename: W H
authors.initials: WH
authors.lastname: Sun
authors.forename: B
authors.initials: B
authors.lastname: Stebler
authors.forename: W B
authors.initials: WB
authors.lastname: Ershler
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D002999:Clone Cells; D006133:Growth Substances / Q000302:isolation & purification* / Q000494:pharmacology; D008214:Lymphocytes / Q000276:immunology / Q000502:physiology*; D008297:Male; D008546:Melanoma, Experimental; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000502:physiology*
chemical_list: D006133:Growth Substances