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Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
 6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two growth factors, interleukin 2 (T cell growth factor) and colony-stimulating factor, are produced concomitantly by a murine EL-4 thymoma cell line after stimulation by phorbol myristate acetate. As shown elsewhere, these thymoma-derived factors appear to be biochemically and functionally indistinguishable from the interleukin 2 and colony-stimulating factor produced by mitogen-stimulated mouse spleen cells. Both factors co-elute during gel filtration with apparent m.w. in the range of 30,000, and both exhibit overlapping isoelectric point profiles between pH 4 and pH 5. Because we were unable to separate these 2 factors by methods based on either m.w. or charge, we have used phenyl-Sepharose chromatography, a method based on hydrophobic interactions, to completely separate murine interleukin 2 and colony-stimulating factor. In contrast with published reports, each of the separated factors exhibits unique biologic activities on lymphocytes and macrophages. Interleukin 2 provides help for antibody synthesis in the nude mouse, but neither enhances interferon production by macrophages nor stimulates macrophage growth. Colony-stimulating factor does not enhance antibody synthesis in the nude mouse but does enhance interferon production by macrophages and stimulate macrophage growth.
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PMID:Biologic properties of chromatographically separated murine thymoma-derived Interleukin 2 and colony-stimulating factor. 617 Jun 82

A simple two-step method involving ammonium sulfate precipitation followed by hydrophobic chromatography is described for the separation of T cell growth factor (TCGF) from a number of other factors contained in medium conditioned by concanavalin A-stimulated spleen cells. Thus, granulocyte-macrophage colony-stimulating factor, P cell-stimulating activity, pluripotential stem cell-supporting activity and interferon activity were not detected in TCGF partially purified by these steps. T cell-replacing factor co-purified with TCGF. Macrophage activity factor (MAF) co-purified with TCGF, but the ratio of MAF to TCGF activities was reduced more than 20-fold relative to that in crude conditioned medium. All of the factors were present in the 50-80% saturated ammonium sulfate fraction, however, levels of concanavalin A were reduced by 98% in this step. TCGF, separated in this way from these other regulatory factors will be useful in experiments analyzing the actions of TCGF on mixed populations of cells.
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PMID:Preparation of T cell growth factor free from interferon and factors stimulating hemopoietic cells and mast cells. 618 27

We describe the molecular characteristics of T cell growth factor (TCGF), T cell replacing factor (TRF), and granulocyte-macrophage colony-stimulating factor (GM-CSF) produced by a T cell hybridoma after stimulation with concanavalin A (Con A). All three activities could be separated from Con A itself by ammonium sulfate precipitation. The TRF and TCGF activities had a m.w. of 35,000 to 40,000 on gel filtration in phosphate-buffered saline (PBS). Their m.w. were about 30,000 under dissociating conditions in guanidine hydrochloride and about 35,000 to 40,000 under disulfide reducing conditions, suggesting the molecule(s) lacked noncovalent or disulfide-linked subunit structure. GM-CSF had a m.w. of 25,000 to 30,000 by gel filtration in PBS and about 23,000 in guanidine hydrochloride. TRF and TCGF on the one hand and GM-CSF on the other could be distinguished by the criteria of m.w., relative heat sensitivity, and hydrophobic chromatography. TCGF could not be separated from TRF by any of these methods. In terms of all the above properties, factor derived from the T cell hybridoma and spleen cells appeared identical.
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PMID:Biochemical characterization of regulatory factors derived from T cell hybridomas and spleen cells. I. Separation of T cell growth factor and T cell replacing factor from granulocyte-macrophage colony-stimulating factor. 697 69

Isoelectric focusing demonstrated that T cell growth factor (TCGF), T cell replacing factor (TRF), and granulocyte-macrophage colony-stimulating factor (GM-CSF) derived from concanavalin A-stimulated T cell hybridomas and spleen cells are heterogeneous with respect to charge. The spleen cell-derived TCGF and TRF activities focused with isoelectric points (pI) between 3.5 and 6.5 whereas the range for GM-CSF activity was broader (pI, 3.5 to 8.0). The T cell hybridoma-derived activities were slightly more acidic. Neuraminidase treatment of both hybridoma 123 and spleen cell-derived material resulted in a major peak of each activity (TRF/TCGF pI, 4.9; GM-CSF pI, 4.7). Neuraminidase treatment of hybridoma T6-derived material resulted in peaks of TRF and TCGF around 6.0 as well as one around 5.0, suggesting that this charge heterogeneity was due to causes other than variations in the level of sialic acid on the relevant molecules. Tunicamycin-treated spleen cells or hybridoma 123 cells released biologically active TCGF, TRF, and GM-CSF. Each of these three activities from tunicamycin-treated spleen cells focused with pI around 5.0. A major fraction of TRF, TCGF, and GM-CSF activities bound to wheat-germ agglutinin. GM-CSF also bound to concanavalin A and lentil lectin. These results suggest that the molecules responsible for TCGF, TRF, and GM-SCF activities are glycosylated and that the observed heterogeneity in charge and lectin-binding characteristics is due in part to variable glycosylation. Glycosylation was not critical for any of the three biologic activities. No conclusive separation of TRF and TCGF activities was observed in these experiments although GM-CSF differed from TRF and TCGF in that it bound to Concanavalin A.
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PMID:Biochemical characterization of regulatory factors derived from T cell hybridomas and spleen cells. II. Evidence for glycosylation of T cell growth factor, T cell replacing factor, and granulocyte-macrophage colony-stimulating factor. 697 70

The production of multipotential hemopoietic stem cells (CFUs) in cultures of murine bone marrow cells is supported by medium conditioned by concanavalin A-stimulated T cell hybridoma 123 or spleen cells. We present physiochemical evidence that this activity of these conditioned media, which we have operationally termed CFUs-stimulating activity (CFUs-SA), is due to a new T cell-derived lymphokine. CFUs-SA was shown by gel filtration to reside in a distinct fraction corresponding to a mean apparent m.w. of 29,000, and was distinguishable from T cell growth factor, not only by its lower apparent m.w. but also by chromatography using Phenyl-Sepharose. After isoelectric focusing of neuraminidase-treated conditioned medium, CFUs-SA was found between isoelectric points 5 and 8. In this respect, CFUs-SA appeared similar to another factor, P cell-stimulating factor, which stimulates the growth of persisting (P) cells (homogeneous populations of cells resembling mast cells) and that occurred together with CFUs-SA in both the spleen and hybridoma-conditioned media. Isoelectric focusing separated CFUs-SA from granulocyte-macrophage colony-stimulating factor, which focused as a single peak with an isoelectric point around 5.0. Thus CFUs-SA is due to a T cell-derived factor that is separable from T cell growth factor and T cell-derived granulocyte-macrophage colony-stimulating factor, but has similar properties to P cell-stimulating factor.
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PMID:A T cell-derived factor stimulating multipotential hemopoietic stem cells: molecular weight and distinction from T cell growth factor and T cell-derived granulocyte-macrophage colony-stimulating factor. 697 67