Ghaderi Daniel D, Aronson Matthew R, Mehta Amrita, Friedman Ryan M, McDaid Kendra S, Giordano Terri, Jacobs Ian N, Gottardi Riccardo
Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Division of Otolaryngology, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
Laryngoscope. 2025 Jan;135(1):409-415. doi: 10.1002/lary.31754. Epub 2024 Sep 14.
Pediatric subglottic stenosis (SGS) is characterized by subglottic narrowing which occurs when pathological fibroblasts deposit extracellular matrix that reduces airway patency. Recent clinical observations have suggested that azithromycin may have favorable impacts on SGS reduction while treating airway infections; furthermore, our recent work in mice demonstrated that the airway microbiome influences SGS. In this work, we characterize the protective effect of azithromycin as an immunomodulatory and antibacterial therapeutic against subglottic stenosis.
Immunomodulatory and antifibrotic effects of azithromycin were assessed on TGF-β1-stimulated airway fibroblasts at 10 μg/mL for 5 days. Changes in gene expression were quantified by RT-qPCR and myofibroblast differentiation by α-SMA immunostaining. Murine airways were pretreated (2-weeks) with intranasal azithromycin before SGS injury by a twisted wire brush. Disease severity and immune response were characterized by histology and immunostaining for immune cells.
In vitro, azithromycin treatment of TGF-β1-stimulated fibroblasts exhibited strong reductions in extracellular matrix (COL1A1, LOX) and myofibroblast-related gene expression (ACTA2). Notably, there was a significant reduction in pro-fibrotic expression, which was observed with 10 μg/mL azithromycin. Immunostaining of fibroblasts for α-SMA revealed strong reductions in the number of positive-staining cells and the intensity of each positive cell. In vivo, azithromycin exhibited a significant decrease in lamina propria thickness indicative of reduced stenosis with associated changes in T-cell infiltration.
Overall, we show azithromycin prevents pro-fibrotic gene expression and myofibroblast differentiation and can help protect mice from developing SGS. This introduces azithromycin as a potential treatment for SGS.
NA Laryngoscope, 135:409-415, 2025.
小儿声门下狭窄（SGS）的特征是声门下狭窄，当病理性成纤维细胞沉积细胞外基质从而降低气道通畅性时就会发生这种情况。最近的临床观察表明，阿奇霉素在治疗气道感染时可能对减轻SGS有有利影响；此外，我们最近在小鼠身上的研究表明气道微生物群会影响SGS。在这项研究中，我们将阿奇霉素作为一种免疫调节和抗菌疗法，对其针对声门下狭窄的保护作用进行了特征描述。
在10μg/mL浓度下，对经转化生长因子-β1（TGF-β1）刺激的气道成纤维细胞进行为期5天的阿奇霉素免疫调节和抗纤维化作用评估。通过逆转录定量聚合酶链反应（RT-qPCR）对基因表达变化进行定量，并通过α-平滑肌肌动蛋白（α-SMA）免疫染色对肌成纤维细胞分化进行评估。在通过扭线刷造成SGS损伤之前，用鼻内阿奇霉素对小鼠气道进行预处理（2周）。通过组织学和免疫细胞免疫染色对疾病严重程度和免疫反应进行特征描述。
在体外，用阿奇霉素处理经TGF-β1刺激的成纤维细胞后，细胞外基质（COL1A1、赖氨氧化酶）和肌成纤维细胞相关基因表达（ACTA2）显著降低。值得注意的是，在10μg/mL阿奇霉素处理组中观察到促纤维化表达显著降低。对成纤维细胞进行α-SMA免疫染色显示，阳性染色细胞数量和每个阳性细胞的强度均显著降低。在体内，阿奇霉素使固有层厚度显著降低，这表明狭窄减轻，同时T细胞浸润也有相关变化。
总体而言，我们发现阿奇霉素可预防促纤维化基因表达和肌成纤维细胞分化，并有助于保护小鼠不发生SGS。这表明阿奇霉素是一种潜在的SGS治疗方法。
NA 《喉镜》，2025年，第135卷，第409 - 415页
