PURIFICATION AND CHARACTERIZATION OF A HUMAN LYMPHOCYTE-T-DERIVED GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR

Abstract

The biologic and physical properties of a human T lymphocyte granulocyte-macrophage colony-stimulating factor (CSF) were examined. The source of the factor is a T-lymphoblast cell line (Mo) that was derived from a patient with a T-cell variant of hairy-cell leukemia. The Mo line constitutively produces a number of lymphokines that are normally produced by mitogen-stimulated T lymphocytes. Medium conditioned by Mo cells grown in the absence of serum is especially rich in CSF activity; using this source, the CSF was purified to a specific activity of about 3.5 .times. 106 colonies per 105 Ficoll-Hypaque-separated human bone marrow cells plated per mg protein. The Mo CSF stimulates the formation of granulocyte and macrophage colonies in vitro (in about equal numbers), it has a relatively steep dose-response curve. Both the crude and purified preparations stimulated the formation of eosinophil and neutrophil colonies; it is unclear whether this is due to the presence of multiple factors with multiple activies. The CSF has little stimulating activity for mouse bone marrow progenitors. Physically, the Mo CSF is an acidic glycoprotein of MW about 34,000. It binds to concanavalin A-Sepharose, is unusually resistant to denaturing agents and heat treatment and is not inactivated in the presence of sulfhydryl reagents. The Mo CSF is distinct from factors stimulating erythroid colony formation and inhibition neutrophil migration that are also produced by Mo cells. It differs in several physical and biologic properties from other human CSF that have been characterized.