Search results for "Interleukin 3."
showing 6 items of 76 documents
Human interleukin-4 enhances stromal cell-dependent hematopoiesis: costimulation with stem cell factor
1994
Abstract Interleukin-4 (IL-4) has distinct hematopoietic activities, primarily as a costimulant with other cytokines to enhance colony formation of hematopoietic progenitors. We investigated the influence of IL-4 on stromal cell-supported long-term cultures (LTCs) of normal human bone marrow. Addition of IL-4 to LTCs of unseparated bone marrow or highly enriched CD34+ cells resulted in a significant increase of myeloid progenitors in the nonadherent, as well as in the stromal cell-adherent cell populations. In contrast, the total cell number was not influenced by IL-4, suggesting a selective effect on primitive progenitor cells. Cord blood cells or CD34+ bone marrow cells were incubated wit…
Characterization of a T cell-derived lymphokine that acts synergistically with IL 3 on the growth of murine mast cells and is identical with IL4
1987
Abstract A mast cell-like cell line (SN-1) was established with the aid of growth factor(s) present in the supernatant of a Con A-stimulated L3T4 + T cell line. In analogy to other mast cell lines, IL 3 was identified as a growth factor for SN-1 cells. In addition, a second lymphokine produced by the T cells synergistically enhanced the IL 3-induced growth. This factor, originally termed mast cell growth enhancing factor (MaGEF), could be separated from IL 2, IL 3, a CSF-like activity and was purified to homogeneity. The N-terminal amino acid sequence (8 residues) and the functional properties of this lymphokine proved to be identical with those reported for BSF-1 (IL 4). Unless applied at …
The Streptococcal Exotoxin Streptolysin O Activates Mast Cells To Produce Tumor Necrosis Factor Alpha by p38 Mitogen-Activated Protein Kinase- and Pr…
2003
ABSTRACTStreptolysin O (SLO), a major virulence factor of pyogenic streptococci, binds to cholesterol in the membranes of eukaryotic cells and oligomerizes to form large transmembrane pores. While high toxin doses are rapidly cytocidal, low doses are tolerated because a limited number of lesions can be resealed. Here, we report that at sublethal doses, SLO activates primary murine bone marrow-derived mast cells to degranulate and to rapidly induce or enhance the production of several cytokine mRNAs, including tumor necrosis factor alpha (TNF-α). Mast cell-derived TNF-α plays an important protective role in murine models of acute inflammation, and the production of this cytokine was analyzed…
Oncostatin M, leukaemia-inhibitory factor and interleukin 6 trigger different effects on alpha1-proteinase inhibitor synthesis in human lung-derived …
1998
Interleukin 6 (IL-6), oncostatin M (OSM) and leukaemia-inhibitory factor (LIF) share a common signal-transducing subunit in each of their receptors and thus mediate an overlapping spectrum of biological activities. Although all of these cytokines stimulate the production of α1-proteinase inhibitor (α1-PI) in hepatocyte-derived cells, only OSM is able to up-regulate levels of this inhibitor in epithelial cells originating from the lung. In this study we characterized human lung-derived epithelial-like HTB58 cells for their ability to synthesize α1-PI after treatment with IL-6, OSM and LIF. The results demonstrate that the resistance of HTB58 cells to the effects of IL-6 and LIF was not becau…
Interleukin-32 in systemic sclerosis, a potential new biomarker for pulmonary arterial hypertension
2020
Abstract Background Pulmonary arterial hypertension (PAH) is a severe complication of systemic sclerosis (SSc), associated with a progressive elevation in pulmonary vascular resistance and subsequent right heart failure and death. Due to unspecific symptoms, the diagnosis of PAH is often delayed. On this basis, it is of great value to improve current diagnostic methods and develop new strategies for evaluating patients with suspected PAH. Interleukin-32 (IL-32) is a proinflammatory cytokine expressed in damaged vascular cells, and the present study aimed to assess if this cytokine could be a new biomarker of PAH during SSc. Methods The IL-32 expression was evaluated in the sera and skin sam…
Growth factors and cell kinetics: a mathematical model applied to Il-3 deprivation on leukemic cell lines.
1992
We assume the existence of a specific G1 protein which is an initiator of DNA replication. This initiator is supposed to be synthesized according to Michaelis-Menten kinetics. In order to start DNA replication, it is assumed that this G1 specific protein must be produced in a required amount. Intra-cellular growth inhibitors and extra-cellular growth factors control the production of the initiator. This model allows to calculate the average G1 phase time as a function of the various chemical concentrations of nutrients, enzymes, growth inhibitors and growth factors. This model is compared to cell kinetics experiments on a leukemic cell line responding to Interleukin 3 deprivation. The curve…