Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, 330006, China.
Sci Rep. 2022 Mar 30;12(1):5411. doi: 10.1038/s41598-022-09467-4.
The CCR3 gene plays a critical role in allergic airway inflammation, such as allergic rhinitis (AR), and there is an inflammatory signal link between the nasal cavity and the CCR3 gene in bone marrow. However, the effects of the CCR3 gene in bone marrow cells on AR are not clear. The present study investigated the roles and underlying mechanisms of the bone marrow CCR3 gene in AR mice. Conditional knockout of the bone marrow CCR3 gene (CKO) in mice was generated using the Cre-LoxP recombination system, and offspring genotypes were identified using polymerase chain reaction (PCR). An ovalbumin-induced AR model was established in CKO and wild-type mice to measure eosinophilic inflammation and the Th2 immune response. The following mechanisms were explored using a specific PI3K/AKT pathway inhibitor (Ly294002). We successfully constructed and bred homozygous CKO mice and confirmed a significant increase in CCR3 expression and PI3K/AKT pathway activity in AR mice. Deficiency of the bone marrow CCR3 gene caused a remarkable reduction of CCR3 expression and the PI3K/AKT signaling pathway activity, inhibited histopathological lesions and eosinophil infiltration of the nasal cavity, and reduced the production of Th2 cytokines in serum, which led to the remission of allergic symptoms in AR mice. Ly294002 treatment also decreased these inflammatory indexes in a concentration-dependent manner and blocked inflammatory signals from CCR3, but it did not affect the high expression of CCR3 in AR mice. Collectively, our results suggest that conditional knockout of the bone marrow CCR3 gene can reduce eosinophilic inflammation and the Th2 immune response, which may be due to inhibition of the PI3K/AKT pathway.
CCR3 基因在过敏性气道炎症中发挥关键作用,例如过敏性鼻炎(AR),并且鼻腔和骨髓中的 CCR3 基因之间存在炎症信号联系。然而,骨髓细胞中的 CCR3 基因对 AR 的影响尚不清楚。本研究探讨了骨髓 CCR3 基因在 AR 小鼠中的作用及其潜在机制。使用 Cre-LoxP 重组系统在小鼠中生成骨髓 CCR3 基因条件敲除(CKO),并使用聚合酶链反应(PCR)鉴定后代基因型。在 CKO 和野生型小鼠中建立卵清蛋白诱导的 AR 模型,以测量嗜酸性粒细胞炎症和 Th2 免疫反应。使用特定的 PI3K/AKT 通路抑制剂(Ly294002)探索以下机制。我们成功构建并繁殖了纯合 CKO 小鼠,并在 AR 小鼠中证实 CCR3 表达和 PI3K/AKT 通路活性显著增加。骨髓 CCR3 基因缺失导致 CCR3 表达和 PI3K/AKT 信号通路活性显著降低,抑制了鼻腔的组织病理学损伤和嗜酸性粒细胞浸润,并减少了血清中 Th2 细胞因子的产生,从而导致 AR 小鼠过敏症状缓解。Ly294002 处理也以浓度依赖性方式降低了这些炎症指标,并阻断了 CCR3 的炎症信号,但不影响 AR 小鼠中 CCR3 的高表达。总之,我们的结果表明,骨髓 CCR3 基因的条件敲除可以减少嗜酸性粒细胞炎症和 Th2 免疫反应,这可能是由于抑制了 PI3K/AKT 通路。