Toll-like receptor 7 (TLR7) is known for eliciting immunity against single-stranded RNA viruses, and is increased in both human and cigarette smoke (CS)-induced, experimental chronic obstructive pulmonary disease (COPD). Here we show that the severity of CS-induced emphysema and COPD is reduced in TLR7-deficient mice, while inhalation of imiquimod, a TLR7-agonist, induces emphysema without CS exposure. This imiquimod-induced emphysema is reduced in mice deficient in mast cell protease-6, or when wild-type mice are treated with the mast cell stabilizer, cromolyn. Furthermore, therapeutic treatment with anti-TLR7 monoclonal antibody suppresses CS-induced emphysema, experimental COPD and accumulation of pulmonary mast cells in mice. Lastly, TLR7 mRNA is increased in pre-existing datasets from patients with COPD, while TLR7+ mast cells are increased in COPD lungs and associated with severity of COPD. Our results thus support roles for TLR7 in mediating emphysema and COPD through mast cell activity, and may implicate TLR7 as a potential therapeutic target.
In the present study, Karanjin and Pongapin, two important furanoflavone, constituents of Pongamia pinnata were studied in the management of Psoriasis. Presently, we have experimentally studied the free radical quenching property of Karanjin and Pongapin. A modified method was used to estimate the scavenging effect of the Karanjin (the highest activity of 95.60%) and Pongapin (68.05%) compared to the ascorbic acid as standard (11.60%) against nitric oxide. Furthermore, Molecular docking studies were performed using CLC drug discovery workbench software version 3.0 of the studied flavones (Karanjin and Pongapin) with the receptors responsible for psoriasis (viz. IL-17A, IL-17F, IL-23, RORγt, and TLR-7). Docking scores of Karanjin and Pongapin with different studied receptors were found to be comparable to that of Methotrexate, a known drug for treating Psoriasis. Docking results suggest that Karanjin and Pongapin might also help in controlling the disease. Overall, our results indicate that flavones (Karanjin and Pongapin) could be a natural and better alternative in curing psoriasis without any side effects.
Plasmacytoid dendritic cells (pDC) are activators of innate and adaptive immune responses that express HLA-DR, toll-like receptor (TLR) 7, TLR9 and produce type I interferons. The role of human pDC in malaria remains poorly characterised. pDC activation and cytokine production were assessed in 59 malaria-naive volunteers during experimental infection with 150 or 1,800 P. falciparum-parasitized red blood cells. Using RNA sequencing, longitudinal changes in pDC gene expression were examined in five adults before and at peak-infection. pDC responsiveness to TLR7 and TLR9 stimulation was assessed in-vitro. Circulating pDC remained transcriptionally stable with gene expression altered for 8 genes (FDR