Project description:Piezo1 is a mechanosensitive ion channel that has gained recognition for its role in regulating diverse physiological processes. However, the influence of Piezo1 in inflammatory disease, including infection and tumor-immunity, is not well-studied. We postulated that Piezo1 links physical forces to immune regulation in myeloid cells. We discovered signal transduction via Piezo1 in myeloid cells and established this channel as the primary sensor of mechanical stress in these cells. Global inhibition of Piezo1 was protective against both cancer and septic shock and resulted in a diminution in suppressive myeloid cells. Moreover, deletion of Piezo1 in myeloid cells protected against cancer and increased survival in poly-microbial sepsis. Mechanistically, we show that mechanical stimulation promotes Piezo1-dependent myeloid cell expansion by suppressing Rb. We further show Piezo1-mediated silencing of Rb is regulated via upregulation of HDAC2. Collectively, our work uncovers Piezo1 as a targetable immune checkpoint that drives immune-suppressive myelopoiesis in cancer and infectious disease.
Project description:Although cells of the immune system experience force and pressure throughout their lifecycle, almost nothing is known about how these mechanical processes regulate the immune response. Immune cells in highly mechanical organs, such as the lung, are constantly exposed to tonic and dynamically changing mechanical cues. Here using reverse genetics, we show that myeloid cells respond to force and alterations in cyclical hydrostatic pressure (CHP) via the mechanosensory ion channel (MSIC) PIEZO1. Unbiased RNA-sequencing from macrophages subjected to CHP reveals a striking state of proinflammatory reprogramming. We report a novel mechanosensory-immune signaling circuit which PIEZO1 initiates in response to CHP, activating c-JUN, upregulating Endothelin-1 (EDN1), and stabilizing HIF1α to facilitate a prolonged program of proinflammatory mediators. Using mice conditionally deficient of PIEZO1 in myeloid cells, and cellular depletion assays, we show infiltrating monocytes respond to cyclical force to recruit neutrophils and clear pulmonary Pseudomonas aeruginosa infection. Furthermore, myeloid PIEZO1 also drove lung pathology in a mouse model of pulmonary fibrosis. Our results demonstrate a novel environmental sensory axis that myeloid cells recognize to mount an inflammatory response, and is the first report showing a physiological role for PIEZO1 and mechanosensation in immunity.
Project description:Mechanosensitive ion channels sense force and pressure in immune cells to drive the inflammatory response in highly mechanical organs. Here we report that Piezo1 channels repress group 2 innate lymphoid cells (ILC2s)-driven type 2 inflammation in the lungs. Piezo1 is induced on lung ILC2s upon activation, as genetic ablation of Piezo1 in ILC2s increases their function and exacerbates the development of airway hyperreactivity (AHR). Conversely, Piezo1 agonist Yoda1 reduces ILC2-driven lung inflammation. Mechanistically, Yoda1 inhibits ILC2 cytokine secretion and proliferation in a KLF2-dependent manner, as we further found that Piezo1 engagement reduces ILC2 oxidative metabolism. Consequently, in vivo Yoda1 treatment notably reduces the development of AHR in experimental models of ILC2-driven allergic asthma. Human circulating ILC2s express and induce Piezo1 upon activation, as Yoda1 treatment of humanized mice reduces human ILC2-driven AHR. Our studies define Piezo1 as a critical regulator of ILC2s and we propose the potential of Piezo1 activation as a novel therapeutic approach for the treatment of ILC2-driven allergic asthma.
Project description:Mechanosensitive ion channels sense force and pressure in immune cells to drive the inflammatory response in highly mechanical organs. Here we report that Piezo1 channels repress group 2 innate lymphoid cells (ILC2s)-driven type 2 inflammation in the lungs. Piezo1 is induced on lung ILC2s upon activation, as genetic ablation of Piezo1 in ILC2s increases their function and exacerbates the development of airway hyperreactivity (AHR). Conversely, Piezo1 agonist Yoda1 reduces ILC2-driven lung inflammation. Mechanistically, Yoda1 inhibits ILC2 cytokine secretion and proliferation in a KLF2-dependent manner, as we further found that Piezo1 engagement reduces ILC2 oxidative metabolism. Consequently, in vivo Yoda1 treatment notably reduces the development of AHR in experimental models of ILC2-driven allergic asthma. Human circulating ILC2s express and induce Piezo1 upon activation, as Yoda1 treatment of humanized mice reduces human ILC2-driven AHR. Our studies define Piezo1 as a critical regulator of ILC2s and we propose the potential of Piezo1 activation as a novel therapeutic approach for the treatment of ILC2-driven allergic asthma.
Project description:In gastric cancer (GC), PIEZO1 was suggested to promote cell migration by interacting with Trefoil factor family 1 (TFF1) and serve as a therapeutic target against invasion and metastasis. In addition, PIEZO1 demonstrates abundant expression in most GC cell lines and primary samples and highly-expressed PIEZO1 is associated with poor disease-specific survival. As Yoda1 is known to be an agonist of PIEZO1, we try to explore the PIEZO1 function in GC by Yoda1 treatment.
Project description:Innate immunity is expected to play a primary role in conferring resistance to novel infectious diseases, but few studies have attempted to examine its role in the evolution of resistance to emerging pathogens in wild vertebrate populations. Here we used experimental infections and cDNA microarrays to examine whether changes in the innate and/or acquired immune responses likely accompanied the emergence of resistance in house finches (Carpodacus mexicanus) in the eastern United States subject to a recent outbreak of conjunctivitis-causing bacterium (Mycoplasma gallisepticum- MG). Three days following experimental infection with MG, we observed differences in the splenic transcriptional responses between House Finches from eastern U.S. populations, with a 12-year history of MG exposure, versus western U.S. populations, with no history of exposure to MG. In particular, western birds down-regulated gene expression, while eastern finches showed no expression change relative to controls. Studies involving poultry have shown that MG can manipulate host immunity, and our observations suggest that pathogen manipulation occurred only in finches from the western populations, outside the range of MG. Fourteen days after infection, eastern finches, but not western finches, up-regulated genes associated with acquired immunity (cell-mediated immunity) relative to controls. These observations suggest population differences in the temporal course of the response to infection with MG, and imply that innate immune processes were targets of selection in response to MG in the eastern U.S. population. Birds were randomly selected to be kept either as controls or infected via ocular inoculation with 20 μl of culture containing 1 x 104 to 1 x 106 color changing units/ml of an early 2007 Auburn MG isolate. All infected birds were inoculated with precisely the same volume of the same culture. Control birds were sham infected using sterile SP4 medium (Whitcomb 1983). Infected birds were euthanized three days (N=6 from Arizona and N=11 from Alabama) and 14 days (N=11 from Arizona and N=12 from Alabama) after treatment. Control birds were euthanized 14 days after sham-inoculation; Control (N=11 birds from Arizona and 9 from Alabama) and infected birds were maintained under identical conditions, but in separate rooms of an aviary. Infected birds were euthanized three days (N=6 from Arizona and N=11 from Alabama) and 14 days (N=11 from Arizona and N=12 from Alabama) after treatment. Control birds were euthanized 14 days after sham-inoculation. We used a common reference design (Yang & Speed 2002), in which we pooled 2 to 6 spleens from birds from the same population in the same treatment to generate enough mRNA for microarray hybridizations and hybridized two pools for each treatment from each population.
Project description:Innate immunity is expected to play a primary role in conferring resistance to novel infectious diseases, but few studies have attempted to examine its role in the evolution of resistance to emerging pathogens in wild vertebrate populations. Here we used experimental infections and cDNA microarrays to examine whether changes in the innate and/or acquired immune responses likely accompanied the emergence of resistance in house finches (Carpodacus mexicanus) in the eastern United States subject to a recent outbreak of conjunctivitis-causing bacterium (Mycoplasma gallisepticum- MG). Three days following experimental infection with MG, we observed differences in the splenic transcriptional responses between House Finches from eastern U.S. populations, with a 12-year history of MG exposure, versus western U.S. populations, with no history of exposure to MG. In particular, western birds down-regulated gene expression, while eastern finches showed no expression change relative to controls. Studies involving poultry have shown that MG can manipulate host immunity, and our observations suggest that pathogen manipulation occurred only in finches from the western populations, outside the range of MG. Fourteen days after infection, eastern finches, but not western finches, up-regulated genes associated with acquired immunity (cell-mediated immunity) relative to controls. These observations suggest population differences in the temporal course of the response to infection with MG, and imply that innate immune processes were targets of selection in response to MG in the eastern U.S. population.
Project description:In gastric cancer (GC), PIEZO1 was suggested to promote cell migration by interacting with Trefoil factor family 1 (TFF1) and serve as a therapeutic target against invasion and metastasis. In addition, PIEZO1 demonstrates abundant expression in most GC cell lines and primary samples and highly-expressed PIEZO1 is associated with poor disease-specific survival. Thus, we try to explore the PIEZO1 function in GC by knocking down assay.
Project description:The mechanisms by which physical forces regulate cells to determine complexities of vascular structure and function are enigmatic. Here we show the role the ion channel subunit Piezo1 (FAM38A). Disruption of mouse Piezo1 gene disturbed vascular development and was embryonic lethal within days of the heart beating to cause blood flow. Importance of Piezo channels as sensors of blood flow was indicated by Piezo1 dependence of shear stress-evoked ionic current and calcium influx in endothelial cells and the ability of exogenous Piezo1 to confer shear stress sensitivity on cells that otherwise lacked. Downstream of this calcium influx was proteoase activity and spatial organization of endothelial cells to the polarity of the applied force. Without Piezo1, normal endothelial cell organization was lacking. The data suggest Piezo1 channels as pivotal integrators of vascular architacture with physiological mechanical force.