Interleukin 1 stimulates granulocyte macrophage colony-stimulating activity release by vascular endothelial cells.

Abstract

Studies designed to characterize monocyte-derived recruiting activity (MRA) a monokine that stimulates endothelial cells to produce granulocyte macrophage-colony-stimulating activity (CSA) by endothelial cells, show that it is a thermolabile protein of from 12,000 to 24,000 D which, on chromatofocusing, shows three separate peaks of eluted activity from pH 7.5 to 5.0. Because these and many other properties of MRA are identical to those of interleukin 1 (IILi), we tested the hypothesis that MRA and IL-I are identical. We cultured vascular endothelial cells with various concentrations of purified native and recombinant IL-i (pI 7 form), then tested the endothelial cell supernatants for GM-CSA. Purified native IL-i and recombinant IL-i stimulated endothelial cells to release CSA. The MRA of native IL-1, recombinant IIL-, and unfractionated monocyte conditioned medium was neutralized by a highly specific rabbit anti-human IL-1 antiserum. Chromatofocusing fractions that contained MRA contained immunoreactive IL-1 on immunoblotting and the bioactivity was neutralized completely by treatment with the antiserum. We conclude that IL-i induces the release of CSA by vascular endothelial cells, that IL-1 is constitutively produced by monocytes in vitro, and that MRA and IL-i are biologically, biophysically and, immunologically identical.

Endothelial cell support of hematopoiesis is differentially altered by IL-1 and glucocorticoids

“…[37][38][39][40][41][42][43][44][45][46][47] The relationship between the production of these cytokines and the functional ability of EC to support hematopoiesis may help in understanding the role played by these cells in the ontogeny of the hematopoietic system as EC are intimately associated with embryonic hematopoiesis and may be involved in the development of embryonic progenitors. 52,53 EC are also part of the bone marrow stromal microenvironment.…”

“…[37][38][39][40][41][42][43][44][45][46][47] The functional importance of this production remains to be fully appreciated. As a direct relevant application, EC may for instance offer an improved alternative to unfractionated stroma cells as a source of feeder cells in bioreactors devised for ex vivo expansion of hematopoietic progenitors.…”

Expression of ras oncogenes in cultured human cells alters the transcriptional and posttranscriptional regulation of cytokine genes.

“…ony-stimulating factor (GM-CSF), granulocyte CSF (G-CSF), macrophage CSF (M-CSF), IL-l, and IL-6 by human cells are complex and poorly understood (1)(2)(3)(4). These cytokines can be produced by a wide variety of normal cell types, including T lymphocytes, monocytes, B lymphocytes, fibroblasts, vascular endothelial cells, certain epithelial cells, and mesothelial cells (1)(2)(3)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). The production of each of these glycoprotein factors may be induced in normal cells by exposure to specific stimuli such as bacterial endotoxin or tumor necrosis factor (TNF) (5)(6)(7)(8)(9)(10)(11)(12)(13)(15)(16)(17)(18)(19).…”

Dexamethasone regulation of the expression of cytokine mRNAs induced by interleukin‐1 in the astrocytoma cell line U373MG

“…Its biological activities include induction of various cytokines. IL-1 has been shown to induce the production of granulocytemacrophage colony-stimulating factor [5][6][7][8][9][10][11][12][13], granulocyte CSF (G-CSF) [9][10][11][12] and B-cell stimulatory factor-2/interleukin-6/interferon-fl2 (IFN-~2)/26-kDa protein [14][15][16][17]. Recently it has also been reported that IL-1 can induce its own synthesis [18][19][20].…”