Interaction of eosinophilic and neutrophilic inflammation in patients with chronic rhinosinusitis

Abstract

Purpose of review In the past year, the endotype of chronic rhinosinusitis (CRS) has been studied from a new perspective. Eosinophilic and neutrophilic inflammation are not independent processes in the pathogenesis of CRS. In this review, we will focus on recent research on mixed eosinophilic-neutrophilic inflammation in CRS and discuss the mechanism and potential treatments. Recent findings Traditionally, patients with eosinophilic CRS (ECRS) present with severe clinical manifestations, comorbidities, and a higher recurrence rate. Recent studies have found that approximately 40% of patients with ECRS present with neutrophilic infiltration, while patients with predominantly eosinophilic infiltration along with neutrophilic inflammation present with more complex inflammation, clinical manifestations and exhibit refractory characteristics. Summary The complex inflammatory profile and refractory clinical characteristics of mixed eosinophilic-neutrophilic inflammation in CRS are current challenges for clinicians. We summarize the features of eosinophilic and neutrophilic inflammation and current studies on the mechanisms of mixed eosinophilic-neutrophilic inflammation and suggest potentially effective therapeutic methods. We hope that this review will help with determining precise treatment options for patients.

The role of potassium ion channels in chronic sinusitis

“…Especially potassium ion channels are widely distributed and expressed in various immune cells and are involved in antigen presentation, cell migration, phenotype transformation, and the production of inflammatory cytokines ( Pelletier and Savignac, 2018 ; Sesti et al, 2023 ; Xia et al, 2023 ). Previous studies have revealed that KCa3.1 and KV1.3 are present in T lymphocytes, and their relative expression depends on the type of T cells, including naive memory, effector memory, and central memory ( Chen et al, 2024 ; Sima et al, 2024 ). The potassium channel ERG1 and KV1.3 are involved in the maturation and differentiation of B lymphocytes ( Sima et al, 2024 ).…”

“…Previous studies have revealed that KCa3.1 and KV1.3 are present in T lymphocytes, and their relative expression depends on the type of T cells, including naive memory, effector memory, and central memory ( Chen et al, 2024 ; Sima et al, 2024 ). The potassium channel ERG1 and KV1.3 are involved in the maturation and differentiation of B lymphocytes ( Sima et al, 2024 ). KV1.3, KV1.5, KCa3.1, Kir2.1/2.2, Kir6.1/6.2 and TWIK2, TREK1 can be expressed in monocytes and macrophages, regulating phagocytic function and secreting inflammatory cytokines ( Man et al, 2023 ).…”

“…The pathophysiological basis of CRS involves infiltration of inflammatory cells, aggregation of inflammatory cytokines, and remodeling of the nasal and sinus mucosa ( Bai et al, 2024 ; Xie et al, 2024 ). Chronic inflammation related to CRS exhibits significant heterogeneity and is associated with multiple causes, including anatomical structures, environmental factors, and genetic elements ( Bai et al, 2024 ; Sima et al, 2024 ; Xie et al, 2024 ). CRS is typically classified into two subtypes: CRS without nasal polyps (CRSsNP) and CRS with nasal polyps (CRSwNP) ( Bai et al, 2024 ; Sima et al, 2024 ).…”

“…Chronic inflammation related to CRS exhibits significant heterogeneity and is associated with multiple causes, including anatomical structures, environmental factors, and genetic elements ( Bai et al, 2024 ; Sima et al, 2024 ; Xie et al, 2024 ). CRS is typically classified into two subtypes: CRS without nasal polyps (CRSsNP) and CRS with nasal polyps (CRSwNP) ( Bai et al, 2024 ; Sima et al, 2024 ). CRSsNP is often accompanied by neutrophil infiltration and has a relatively good therapeutic effect, while CRSwNP is often accompanied by inflammation with high eosinophils and has a higher postoperative recurrence rate ( Bai et al, 2024 ; Xie et al, 2024 ).…”