Exhausted CD8 T cells (T) are associated with worse outcome in cancer yet better outcome in autoimmunity. Building on our past findings of increased TIGITKLRG1 T with teplizumab therapy in type 1 diabetes (T1D), in the absence of treatment we found that the frequency of TIGITKLRG1 T is stable within an individual but differs across individuals in both T1D and healthy control (HC) cohorts. This TIGITKLRG1 CD8 T population shares an exhaustion-associated EOMES gene signature in HC, T1D, rheumatoid arthritis (RA), and cancer subjects, expresses multiple inhibitory receptors, and is hyporesponsive , together suggesting co-expression of TIGIT and KLRG1 may broadly define human peripheral exhausted cells.
View Article and Find Full Text PDFIn cancers with tumor-infiltrating lymphocytes (TILs), monoclonal antibodies (mAbs) that block immune checkpoints such as CTLA-4 and PD-1/PD-L1 promote antitumor T-cell immunity. Unfortunately, most cancers fail to respond to single-agent immunotherapies. T regulatory cells, myeloid derived suppressor cells (MDSCs), and extensive stromal networks within the tumor microenvironment (TME) dampen antitumor immune responses by preventing T-cell infiltration and/or activation.
View Article and Find Full Text PDFMetabolic syndrome contributes to cardiovascular disease partly through systemic risk factors. However, local processes in the artery wall are becoming increasingly recognized to exacerbate atherosclerosis both in mice and humans. We show that arterial smooth muscle cell (SMC) glucose metabolism markedly synergizes with metabolic syndrome in accelerating atherosclerosis progression, using a low-density lipoprotein receptor-deficient mouse model.
View Article and Find Full Text PDFInflammatory activation of myeloid cells is accompanied by increased glycolysis, which is required for the surge in cytokine production. Although in vitro studies suggest that increased macrophage glucose metabolism is sufficient for cytokine induction, the proinflammatory effects of increased myeloid cell glucose flux in vivo and the impact on atherosclerosis, a major complication of diabetes, are unknown. We therefore tested the hypothesis that increased glucose uptake in myeloid cells stimulates cytokine production and atherosclerosis.
View Article and Find Full Text PDFMitochondrial dysfunction contributes to numerous health problems, including neurological and muscular degeneration, cardiomyopathies, cancer, diabetes, and pathologies of aging. Severe mitochondrial defects can result in childhood disorders such as Leigh syndrome, for which there are no effective therapies. We found that rapamycin, a specific inhibitor of the mechanistic target of rapamycin (mTOR) signaling pathway, robustly enhances survival and attenuates disease progression in a mouse model of Leigh syndrome.
View Article and Find Full Text PDFThe enzyme acyl-CoA synthetase 1 (ACSL1) is induced by peroxisome proliferator-activated receptor α (PPARα) and PPARγ in insulin target tissues, such as skeletal muscle and adipose tissue, and plays an important role in β-oxidation in these tissues. In macrophages, however, ACSL1 mediates inflammatory effects without significant effects on β-oxidation. Thus, the function of ACSL1 varies in different tissues.
View Article and Find Full Text PDFDietary restriction (DR), the limitation of calorie intake while maintaining proper nutrition, has been found to extend life span and delay the onset of age-associated disease in a wide range of species. Previous studies have suggested that DR can reduce the lethality of environmental toxins. To further examine the role of DR in toxin response, we measured life spans of the nematode Caenorhabditis elegans treated with the mutagenic polyaromatic hydrocarbon, fluoranthene (FLA).
View Article and Find Full Text PDFDopamine-producing neurons fire with both basal level tonic patterns and phasic bursts. Varying affinities of the five dopamine receptors have led to a hypothesis that higher affinity receptors are primarily activated by basal level tonic dopamine, while lower affinity receptors may be tuned to be sensitive to higher levels caused by phasic bursts. Genetically modified mice provide a method to begin to probe this hypothesis.
View Article and Find Full Text PDFMidbrain dopamine (DA) neurons fire in 2 characteristic modes, tonic and phasic, which are thought to modulate distinct aspects of behavior. However, the inability to selectively disrupt these patterns of activity has hampered the precise definition of the function of these modes of signaling. Here, we addressed the role of phasic DA in learning and other DA-dependent behaviors by attenuating DA neuron burst firing and subsequent DA release, without altering tonic neural activity.
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