玫瑰糠疹皮损中朗格汉斯细胞的超微结构

目的运用光镜、电镜研究朗格汉斯细胞（Langerhans Cell,LC）在玫瑰糠疹（pityriasis rosea,PR）发病中的作用.方法免疫组化链霉素生物素蛋白过氧化物酶（SP）法检测分化群1a（CD1a）在31例PR患者皮损中的表达,观察LC的数量、形态及分布,并和17名正常人躯干部皮肤作对照.用透射电镜观察8例PR患者皮损中LC的超微结构的变化并和4名正常人躯干部皮肤作比较.结果与正常皮肤比较,PR皮损中LC的数量明显增多,树突数量增多并变长,而且在LC中Birbeck颗粒显著增多,粗面内质网扩张,线粒体和粗面内质网数目减少、线粒体水肿,嵴消失.结论LC在PR的发病中起重要的作用,它作为皮肤组织中主要的抗原呈递细胞参与介导了迟发型变态反应的发生和皮损的形成.在此过程中LC自身也受到不同程度的损害.

Ultrastructure of Langerhans cell in pityriasis rosea lesions

Purpose To investigate the effect of Langerhans Cell(LC) during the occurrence and development of pityriasis rosea(PR). Methods Thirty-one PR biopsies were selected from PR patients diagnosed by clinic and histopathology.Seventeen healthy skins were selected as normal controls.Cluster of differentiation 1a(CD1a) expression was detected by immunohistochemical method.Eight PR lesions and 4 normal trunk skins were detected by transmission electronic microscope. Results Amount of LC and the length of its dendrite in PR lesions was markedly increased compared with controls(P<0.05).In LC of PR lesions,the Birbeck granules increased and rough endoplasmic reticulum dilated,mitochondria and rough endoplasmic reticulum decreased.And mitochondria edema,disappearance of mitochondria ridge can also be found. Conclusions LC plays an important role in the occurrence of PR.As the main antigen present cells(APC) in skin,LC participates actively in catching,processing,presenting antigens then mediates the occurrence of delayed allergy which probably leads the occurrence of PR lesions and promotes the development of the disease.Furthermore,the LC was injured itself at the same time.