Huang H, Chen P, Ou C Y, Qiu L, Lin Z Z, Huang Z D, Liu W B
Department of Neurology, the First Affiliated Hospital of Sun Yat-sen University; Guangdong Provincial Key Laboratory for Diagnosis and Treatment of Major Neurological Diseases, Guangzhou 510080, China.
Zhonghua Yi Xue Za Zhi. 2017 May 23;97(19):1463-1468. doi: 10.3760/cma.j.issn.0376-2491.2017.19.008.
To investigate the characteristics of the distribution and amount of different subtypes of dendritic cell (DC) in myasthenia gravis(MG). We collected the thymic specimens from 32 patients who received thymoctomy because of cardiac surgery from January 2016 to December 2016 and selected 14 of them as normal control. Meantime, 61 MG patients who combined with thymic hyperplasia and received extended thymectomy were collected and selected 8 of them as experiment group.Immunohistochemical methods were used to label the two subtype DCs: plasmacytoid dendritic cell (pDC) and classical/conventional dendritic cell (cDC), to observe the distribution of these two DC subtypes in thymus and also quantify them in different thymus structures by image analysis software.Comparing with normal thymus of the same age, we intended to demonstrate the characteristics of distribution and density of DC subtypes in patients who had MG and hyperplastic thymus. (1) We labeled pDC and cDC by staining with CD123 and CD11c.The two DC subtypes distributed in both cortex and medulla, and the majority gathered in medulla, the density of pDC in thymus cortex was (34±6)/mm(2)(=14), the density of pDC in thymus medulla was (247±35)/mm(2)(=14), the density of cDC in thymus cortex was (21±4)/mm(2)(=14), the density of cDC in thymus medulla was (123±16)/mm(2) (=14). (2) The density of pDC in thymus cortex and medulla of patients with MG was lower when compared with the normal group (the density of pDC in thymus cortex, [(39±10)/mm(2) vs (29±5)/mm(2)], the density of pDC in thymus medulla, [(279±48)/mm(2) vs (236±49)/mm(2)], but with no significant difference.There was no significant difference between the density of cDC in thymus cortex of patients with MG patients and normal people, however, the amount of cDC increases in medulla and the difference was statistically significant (<0.05). (3) The density of cDC in thymus medulla (except for germinal center) was higher than normal people (110±18) /mm(2) vs (187±29/mm(2)), though the difference was not statistically significant (=0.059 9). The density of cDC in the ectopic germinal center (GC) of MG patients increased obviously compared with that in thymus medulla [(203±44) /mm(2) vs (439±69)/mm(2)] and the difference was statistically significant (<0.05). The density of cDC increases significantly in thymus medulla of MG patients, especially gathering around or in the ectopic GC. It indicates that cDC may play an important role in the formation of ectopic GC in the hyperplasia thymus, thus involves in the disease process.
探讨重症肌无力（MG）患者胸腺中不同亚型树突状细胞（DC）的分布特点及数量。收集2016年1月至2016年12月因心脏手术行胸腺切除术的32例患者的胸腺标本，选取其中14例作为正常对照。同时，收集61例合并胸腺增生并接受扩大胸腺切除术的MG患者，选取其中8例作为实验组。采用免疫组化方法标记两种亚型DC：浆细胞样树突状细胞（pDC）和经典/常规树突状细胞（cDC），观察这两种DC亚型在胸腺中的分布情况，并通过图像分析软件对不同胸腺结构中的DC进行定量分析。与同年龄正常胸腺比较，旨在阐明MG伴胸腺增生患者DC亚型的分布及密度特点。（1）用CD123和CD11c染色标记pDC和cDC。两种DC亚型均分布于皮质和髓质，多数聚集于髓质，胸腺皮质pDC密度为（34±6）/mm²（n = 14），胸腺髓质pDC密度为（247±35）/mm²（n = 14），胸腺皮质cDC密度为（21±4）/mm²（n = 14），胸腺髓质cDC密度为（123±16）/mm²（n = 14）。（2）MG患者胸腺皮质和髓质pDC密度低于正常组（胸腺皮质pDC密度，[(39±10)/mm² 对 (29±5)/mm²]，胸腺髓质pDC密度，[(279±48)/mm² 对 (236±49)/mm²]），但差异无统计学意义。MG患者胸腺皮质cDC密度与正常人无明显差异，然而，髓质中cDC数量增加，差异有统计学意义（P<0.05）。（3）MG患者胸腺髓质（生发中心除外）cDC密度高于正常人（110±18）/mm² 对 (187±29)/mm²，差异无统计学意义（P = 0.059 9）。MG患者异位生发中心（GC）cDC密度较胸腺髓质明显增加[（203±44）/mm² 对 (439±69)/mm²]，差异有统计学意义（P<）。MG患者胸腺髓质cDC密度显著增加，尤其聚集在异位GC周围或内部。这表明cDC可能在增生胸腺中异位GC的形成中起重要作用，从而参与疾病过程。
