0000000000550110
AUTHOR
Lothar Hültner
Murine bone marrow-derived mast cells as potent producers of IL-9: costimulatory function of IL-10 and kit ligand in the presence of IL-1.
Abstract Recently, the Th2-type cytokine IL-9 was identified by genetic mapping analyses as a key mediator that determines the susceptibility to asthma. This has been further supported by data from IL-9-transgenic mice in which the overexpression of IL-9 in the lung causes airway inflammation, mast cell hyperplasia, and bronchial hyperresponsiveness. In an accompanying paper, we demonstrate that murine bone marrow-derived mast cells (BMMC) after stimulation with either ionomycin, a combination of ionomycin and IL-1, or via IgE-Ag complexes and IL-1 are very potent producers of IL-9. Herein we show that a dramatic increase of IL-9 production is observed when BMMC activated with ionomycin/IL-…
IL-9 and IL-13 production by activated mast cells is strongly enhanced in the presence of lipopolysaccharide: NF-kappa B is decisively involved in the expression of IL-9.
Abstract Mast cells, due to their ability to produce a large panel of mediators and cytokines, participate in a variety of processes in adaptive and innate immunity. Herein we report that in primary murine bone marrow-derived mast cells activated with ionomycin or IgE-Ag the bacterial endotoxin LPS strongly enhances the expression of IL-9 and IL-13, but not IL-4. This costimulatory effect of LPS is absent in activated mast cells derived from the LPS-hyporesponsive mouse strain BALB/c-LPSd, although in these cells the proinflammatory cytokine IL-1 can still substitute for LPS. The enhanced production of mast cell-derived IL-13 in the presence of IL-1 is a novel observation. Coactivation of m…
Classical and alternative pathways of mast cell activation.
It has long since been recognized that mast cells are critical effectors of anaphylactic reactions, and the existence of these potentially hazardous cells has solely been justified due to their beneficial role in some infections with extracellular parasites. A novel understanding of mast cells as sentinels of the immune system has been made possible by taking advantage of mast cell-deficient mice in order to study the roles of mast cells in vivo and by detailed analyses of mast cell activation in vitro. Collectively, these experiments have revealed a variety of IgE-independent stimuli, which lead to the activation of mast cells as crucial initiators of an inflammatory response. Besides thei…
Co-activation of naive CD4+ T cells and bone marrow-derived mast cells results in the development of Th2 cells
Activation of naive dense CD4+ T cells by plate-bound anti-CD3 antibodies favors the development of Th1 cells which, upon re-stimulation, produce significant amounts of IFN-gamma but no IL-4. However, co-activation of such naive T cells in the presence of IgE [anti-dinitrophenyl (DNP)]-loaded bone marrow-derived mast cells (BMMC) on plates coated with anti-CD3 antibodies and DNP-BSA led to the development of IL-4-producing Th2 cells. The same result could be observed if irradiated (800 rad) BMMC were applied as co-stimulators. Moreover, BMMC could be replaced by the supernatant of IgE-activated BMMC suggesting that a soluble mediator, presumably IL-4, was responsible for this effect. This a…
Mast cell growth-enhancing activity (MEA) is structurally related and functionally identical to the novel mouse T cell growth factor P40/TCGFIII (interleukin 9).
We have previously shown that certain bone marrow-derived mast cell (BMMC) lines proliferate in response to a mast cell growth-enhancing activity (MEA) that is distinct from interleukin (IL) 3 and IL 4. Here we provide evidence that MEA is identical with the recently cloned mouse T cell growth factor P40. The evidence is as follows: (a) recombinant P40 displayed all the biological activities ascribed to MEA: it supported the growth of MEA-sensitive BMMC lines, it induced IL 6 secretion by these cells, and it enhanced survival of primary mast cell cultures; (b) highly purified MEA stimulated the growth of P40-dependent cell lines; (c) a rabbit monospecific antiserum directed against P40 spec…
In activated mast cells, IL-1 up-regulates the production of several Th2-related cytokines including IL-9.
Abstract Mast cells can play detrimental roles in the pathophysiology and mortality observed in anaphylaxis and other Th2-dominated allergic diseases. In contrast, these cells contribute to protective host defense mechanisms against parasitic worm infections. After IgE/Ag activation, mast cells can produce multiple cytokines that may enhance allergic inflammations, while a similar panel of Th2-related cytokines may support immunological strategies against parasites. Here we report that in primary mouse bone marrow-derived mast cells activated by ionomycin or IgE/Ag, the proinflammatory mediator IL-1 (α or β) up-regulated production of IL-3, IL-5, IL-6, and IL-9 as well as TNF, i.e., cytokin…
The Streptococcal Exotoxin Streptolysin O Activates Mast Cells To Produce Tumor Necrosis Factor Alpha by p38 Mitogen-Activated Protein Kinase- and Protein Kinase C-Dependent Pathways
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…