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Rohm, T. V.

Publications and source records attributed to Rohm, T. V..

3 recordsLinked to original sources

Far-red chemigenetic biosensors for multi-dimensional and super-resolved kinase activity imaging

Fluorescent biosensors revolutionized biomedical science by enabling the direct measurement of signaling activities in living cells, yet the current technology is limited in resolution and dimensionality. Here, we introduce highly sensitive chemigenetic kinase activity biosensors that combine the genetically encodable self-labeling protein tag HaloTag7 with bright far-red-emitting synthetic fluorophores. This technology enables five-color biosensor multiplexing, 4D activity imaging, and functional super-resolution imaging via stimulated emission depletion (STED) microscopy.

bioengineering↗

Air pollution mediates diabetes by disrupting gut innate mucosal immunity

Air pollution has emerged as an unexpected risk factor for diabetes1-6. The mechanisms linking air pollution and diabetes remain, however, unknown. It has been postulated that lung exposure mediates diabetes via systemic inflammation and insulin resistance7-9. By contrast, gut exposure to pollutants has received little attention, even though a large proportion of air pollution particles are swallowed after mucociliary clearance from the upper airways10. Here, we identified intestinal macrophages as key mediators linking air pollutants with impaired beta-cell function. Upon oral exposure to air pollution, intestinal macrophages up-regulated inflammatory- and interferon-response pathways, which disrupted their normal differentiation towards an anti-inflammatory/resident phenotype. The resulting pro-inflammatory milieu in the gut impaired beta-cell identity and function via local cytokine secretion from macrophages as genetic and pharmacological macrophage or IL-1{beta} ablation protected mice from developing air pollution-induced diabetes. These data establish intestinal macrophage-derived cytokines as key mediators of air pollution associated beta-cell dysfunction, thus pointing towards novel therapeutic strategies.

immunology↗

Pharmacological Macrophage Attenuation by Imatinib Reverts Hepatic Steatosis and Inflammation in Obese Mice

AimsNon-alcoholic fatty liver disease (NAFLD) has become one of the most common liver diseases worldwide. As macrophages play a key role in NAFLD, therapies targeting macrophages have been postulated. Indeed, strategies depleting macrophages or blocking monocyte recruitment into the liver improve NAFLD, however, are not feasible in clinical practice. Our goal was to assess whether attenuation of macrophages can be achieved by imatinib, an anti-leukemia drug with known anti-inflammatory and anti-diabetic properties, and how this impacts NAFLD.\n\nMaterials and MethodsMurine macrophages were polarized in vitro to different activation states in the presence or absence of imatinib; mice on high fat diet orally treated with imatinib or vehicle; and human monocytes of diabetic patients and healthy controls treated with or without imatinib for translational application.\n\nResultsImatinib specifically attenuated pro-inflammatory murine macrophages in vitro and in vivo. In livers of obese mice, imatinib caused Kupffer cells to adopt an attenuated phenotype via modulation of the TNF-pathway. This immune-modulation resulted in markedly improved hepatic steatosis along with beneficial effects on liver function, lipids and systemic inflammation. The immune-dampening effect of imatinib also prevailed in human monocytes, indicating translational applicability.\n\nConclusionsImmune-modulation of myeloid cells as exemplified by imatinib may be a novel therapeutic strategy in patients with NAFLD.

immunology↗