Pyruvate kinase M2 in lung APCs regulates Alternaria-induced airway inflammation.

Pyruvate kinase M2 in lung APCs regulates Alternaria-induced airway inflammation. Immunobiology. 2020 Jul;225(4):151956 Authors: Jaiswal AK, Makhija S, Stahr N, Sandey M, Suryawanshi A, Mishra A Abstract Sensitivity to allergenic fungi (Alternaria alternata) is associated with acute, severe asthma attacks. Antigen presenting cells (APCs) in the lung sense environmental perturbations that induce cellular stress and metabolic changes and are critical for allergic airway inflammation. However, the mechanisms underlying such environmental sensing by APCs in the lung remains unclear. Here we show that acute Alternaria challenge rapidly induces neutrophil accumulation in airways, and alter expressions of Pyruvate Kinase (PKM2) and hypoxia-inducible factor -1α (Hif-1α) that correlates with proinflammatory mediator release. Blockade of IL33 signaling in vivo led to reduce oxidative stress and glycolysis in lung APCs. Lung-specific ablation of CD11c+ cells abrogates Alternaria-induced neutrophil accumulation and inflammation. Furthermore, administration of Alternaria into the airways stimulated APCs and elevate the expression of Glut-1. Mechanistically, we establish that PKM2 is a critical modulator of lung APC activation in Alternaria-induced acute inflammation. Allosteric activation of PKM2 by a small molecule ML265 or siRNA-mediated knock down correlated negatively with glycolysis and activation of APCs. These results collectively demons...
Source: Immunobiology - Category: Allergy & Immunology Authors: Tags: Immunobiology Source Type: research