Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
Int Forum Allergy Rhinol. 2013 Aug;3(8):684-7. doi: 10.1002/alr.21176. Epub 2013 May 15.
P-glycoprotein (P-gp) is a membrane-bound efflux pump that is upregulated in chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and participates in epithelial cytokine secretion. Eosinophilic CRS (ECRS) shares a similar cytokine profile with CRSwNP and is associated with significant inflammation and poor surgical outcomes. The goal of this study is to determine if P-gp expression is associated with degree of eosinophilia and severity of radiographic inflammation in patients with CRS without polyps (CRSsNP).
An institutional review board (IRB)-approved study using sinus tissue in 39 steroid-naive patients with CRS. P-gp expression was calculated using quantitative fluorescent immunohistochemistry (Q-FIHC) to generate an epithelial to background staining ratio. Patients were stratified into low and high epithelial expression groups (<3 and ≥3, respectively). Average eosinophils per high powered field (hpf) and Lund-Mackay scores were calculated and compared with P-gp staining ratios using a 2-tailed Student t test.
Among the 39 patients, 7 (17.95%) had high P-gp expression ratios (mean ± SD, 4.86 ± 1.33) while 32 (82.05%) had low expression ratios (1.91 ± 0.45). The number of eosinophils/hpf were significantly greater in the high P-gp expression group as compared to the low expression group (62.38 ± 83.69 vs 5.11 ± 10.12, p = 0.0003). The Lund-Mackay scores were significantly greater in the high P-gp expression group as compared to the low expression group (11.86 ± 2.79 vs 6.84 ± 4.19, p = 0.005).
P-gp is known to be overexpressed in CRSwNP. This study suggests that among patients with CRSsNP, P-gp is similarly overexpressed in those with high tissue eosinophilia and correlates with severity of radiographic inflammation.
P-糖蛋白（P-gp）是一种膜结合的外排泵，在伴有鼻息肉的慢性鼻-鼻窦炎（CRSwNP）中上调，并参与上皮细胞细胞因子的分泌。嗜酸性慢性鼻-鼻窦炎（ECRS）与 CRSwNP 具有相似的细胞因子谱，与显著的炎症和不良手术结果相关。本研究的目的是确定 P-gp 表达是否与无息肉的慢性鼻-鼻窦炎（CRSsNP）患者的嗜酸性粒细胞程度和放射影像学炎症严重程度相关。
一项机构审查委员会（IRB）批准的研究，使用 39 例类固醇初治 CRS 患者的鼻窦组织。使用定量荧光免疫组织化学（Q-FIHC）计算 P-gp 表达，以生成上皮与背景染色比。将患者分为低和高上皮表达组（<3 和≥3，分别）。使用双尾学生 t 检验，计算每个高倍视野（hpf）的平均嗜酸性粒细胞数和 Lund-Mackay 评分，并与 P-gp 染色比进行比较。
在 39 例患者中，7 例（17.95%）具有高 P-gp 表达比（平均值±标准差，4.86±1.33），而 32 例（82.05%）具有低表达比（1.91±0.45）。与低表达组相比，高 P-gp 表达组的嗜酸性粒细胞数/hpf 显著增加（62.38±83.69 与 5.11±10.12，p=0.0003）。与低表达组相比，高 P-gp 表达组的 Lund-Mackay 评分显著增加（11.86±2.79 与 6.84±4.19，p=0.005）。
P-gp 在 CRSwNP 中过度表达。本研究表明，在 CRSsNP 患者中，P-gp 在组织嗜酸性粒细胞高的患者中同样过度表达，与放射影像学炎症的严重程度相关。
