Non-Eosinophilic Chronic Rhinosinusitis With Nasal Polyps: Eosinophil, Basophil, and Neutrophil Blood Counts Before and After Surgery

The role of autophagy regulated by the PI3K/AKT/mTOR pathway and innate lymphoid cells in eosinophilic chronic sinusitis with nasal polyps

BACKGROUND

The PI3K/Akt/mTOR pathway and autophagy are important physiological processes. But their roles in eCRSwNP remains controversial.

METHODS

In this study, we used the eCRSwNP mouse model, PI3K/Akt/mTOR pathway inhibitors, and autophagy inhibitors and activators to investigate the regulatory effects of the PI3K/Akt/mTOR pathway on autophagy, and their effects on eosinophilic inflammation, and tissue remodeling. The role of ILC2s in eCRSwNP was also studied, and the relationship between ILC2s and autophagy was preliminarily determined.

RESULTS

Our results show that eosinophilic inflammation in eCRSwNP mice could be inhibited by promoting the autophagy; otherwise, eosinophilic inflammation could be promoted. Meanwhile, inhibition of the PI3K/Akt/mTOR pathway can further promote autophagy and inhibit eosinophilic inflammation. Meanwhile, inhibiting the PI3K/Akt/mTOR pathway and promoting autophagy can reduce the number of ILC2s and the severity of tissue remodeling in the nasal polyps of eCRSwNP mice.

CONCLUSIONS

We conclude that the PI3K/Akt/mTOR pathway plays roles in eosinophilic inflammation and tissue remodeling of eCRSwNP, in part by regulating the level of autophagy. The downregulation of autophagy is a pathogenesis of eCRSwNP; therefore, the recovery of normal autophagy levels might be a new target for eCRSwNP therapy. Furthermore, autophagy might inhibit eosinophilic inflammation and tissue remodeling, in part by reducing the number of ILC2s.

sCD48 is elevated in non-allergic but not in allergic persistent rhinitis

BACKGROUND

CD48 is a costimulatory receptor of the immune response. Interactions between CD48 and CD244 (2B4) on mast cells and eosinophils suggest that these cells can act synergistically in the 'allergic effector unit' to promote inflammation. This report explores the role of CD48 in persistent allergic (PAR) and non-allergic rhinitis (NAR).

METHODS

In this study, serum was obtained from 70 subjects (45 female, 64%; mean age, 36; range 18-70 years) to estimate the levels of sCD48 and two eosinophils-related parameters, ECP and eotaxin-1/CCL11. Twenty patients with PAR, 15 patients with NAR, and 35 healthy controls were included. The intensity of rhinitis symptoms was estimated by the Total Nasal Symptom Score. We also assessed the fractional exhaled nitric oxide bronchial and nasal fractions (FeNO) and neutrophil to lymphocyte (NLR) and eosinophil to lymphocyte (ELR) ratios.

RESULTS

Significantly higher sCD48 serum levels were observed in the NAR group than in the PAR and control groups, and significant correlations were found between the serum level of sCD48 and the number and percentage of eosinophils. ECP and eotaxin-1/CCL11 serum levels were also found to be significantly higher in the NAR group.

CONCLUSIONS

CD48 may be involved in eosinophilic pathophysiological reactions in non-allergic rhinitis.