Department of Chemical Engineering, University of Utah, Salt Lake City, Utah.
Microscopy Core Facility, University of Utah, Salt Lake City, Utah.
J Allergy Clin Immunol. 2014 Jun;133(6):1728-34.e1. doi: 10.1016/j.jaci.2013.11.024. Epub 2014 Jan 15.
In patients with eosinophilic esophagitis (EoE), eosinophils accumulate and release granule proteins onto esophageal epithelium. However, little is understood about the mechanism of eosinophil degranulation.
To determine and quantify eosinophil degranulation patterns, we studied esophageal biopsy specimens from both the proximal and distal esophagi of 9 randomly selected patients with EoE.
The specimens were fixed in glutaraldehyde, embedded, sectioned, and imaged by means of transmission electron microscopy. Eosinophils and their granules were identified by their distinctive morphology, and all eosinophils and granules were imaged. A total of 1672 images from 18 esophageal specimens were evaluated and graded. Eosinophils were categorized based on membrane integrity and by cytoplasmic vesiculation as evidence of piecemeal degranulation. Granules were categorized based on reversal of staining (eosinophil granule core lightening) and localization within and outside the cells.
The results revealed that greater than 98% of eosinophils infiltrating the esophagus in patients with EoE demonstrate morphologic abnormalities ranging from granule changes with reversal of staining to marked cytoplasmic vesiculation to loss of cellular membrane integrity with cytolytic disruption and release of intact membrane-bound granules into the tissues. Approximately 81% of eosinophils showed membrane disruption. Extracellular granules were abundant in at least 70% of the images, and approximately 50% of these granules showed reversal of staining. On the basis of the prominence of tubulovesicular development, piecemeal degranulation appears closely related to the other morphologic changes seen in patients with EoE.
These findings reveal that eosinophils in esophageal biopsy specimens from patients with EoE are abnormal, with greater than 80% showing cytolysis, and therefore that evaluation by means of light microscopy after hematoxylin and eosin staining might not accurately reflect eosinophil involvement.
在嗜酸性粒细胞性食管炎（EoE）患者中，嗜酸性粒细胞在食管上皮细胞上积聚并释放颗粒蛋白。然而，对于嗜酸性粒细胞脱颗粒的机制知之甚少。
为了确定和量化嗜酸性粒细胞脱颗粒的模式，我们研究了随机选择的 9 名 EoE 患者近端和远端食管的活检标本。
标本用戊二醛固定，包埋，切片，并通过透射电子显微镜进行成像。通过其独特的形态学特征识别嗜酸性粒细胞及其颗粒，对所有的嗜酸性粒细胞和颗粒进行成像。共评估和分级了 18 个食管标本的 1672 张图像。根据细胞膜完整性和细胞质空泡化将嗜酸性粒细胞分为两类，这是嗜酸性粒细胞颗粒碎片脱颗粒的证据。根据染色逆转（嗜酸性粒细胞颗粒核心变亮）和细胞内外定位将颗粒分为两类。
结果显示，EoE 患者食管浸润的嗜酸性粒细胞中，超过 98%的细胞表现出形态异常，从颗粒改变、染色逆转、明显细胞质空泡化到细胞膜完整性丧失、细胞溶解和完整的膜结合颗粒释放到组织中。大约 81%的嗜酸性粒细胞显示细胞膜破裂。至少 70%的图像中存在丰富的细胞外颗粒，其中约 50%的颗粒显示染色逆转。根据管状泡状结构发育的显著程度，嗜酸性粒细胞碎片脱颗粒与 EoE 患者所见的其他形态变化密切相关。
这些发现表明，EoE 患者食管活检标本中的嗜酸性粒细胞异常，超过 80%的细胞发生细胞溶解，因此，苏木精-伊红染色后的光镜评估可能无法准确反映嗜酸性粒细胞的参与。
