Alport综合征与Ⅳ型胶原

Alport′s syndrome and type Ⅳ collagen

为探讨Ａｌｐｏｒｔ综合征时Ⅳ型胶原α链的分布改变，应用间接免疫荧光和免疫电镜的方法，观察了Ⅳ型胶原α１～α６（Ⅳ）和Ⅰ、Ⅲ、Ⅴ和Ⅵ型胶原在肾（１０３例）和皮肤（４０例）组织中的分布。结果：６３％的病例存在α３～α６（Ⅳ）的分布异常；两种异常类型直接与遗传方式有关：在Ｘ染色体连锁显性遗传时，男性肾和皮肤组织中α３～α６（Ⅳ）均消失，女性则呈不连续的节段性分布；在常染色体隐性遗传时，肾小球基底膜（ＧＢＭ）中α３～α５（Ⅳ）均消失，而ＧＢＭ外肾组织基膜中α３～α４（Ⅳ）消失，α５～α６（Ⅳ）的分布完全正常。提示，Ⅳ型胶原α链分布异常是Ａｌｐｏｒｔ综合征的一个诊断标志；皮肤活检观察α５～α６（Ⅳ）的分布有助于Ｘ染色体连锁显性遗传患者及携带者的诊断。

For the purpose of investigating modification of α chains of type Ⅳ collagen in patients with Alport′s syndrome, the renal and epidermal distribution of α1α6 (Ⅳ) and type Ⅰ, Ⅲ, Ⅴ and Ⅵ collagen was observed by indirect immunofluorescence and immune electron microscopy. The results showed that abnormal distribution of α3α6 (Ⅳ) existed in 63% of the patients. Two types of abnormality were found directly related to the forms of transmission of the disease:(1) the renal and epidermal distribution of α3α6 (Ⅳ) completely disappeared in male cases or discontinuously and segmentally presented in female cases of Xlinked Alport′s syndrome; (2) α3α5 (Ⅳ) were negative in glomerular basement membrane and α5α6 (Ⅳ) were positive in the nonglomerular and epidermal basement menbrane where α3α4 (Ⅳ) were negative in patients with autosomal recessive Alport′s syndrome. These results suggest that abnormal distribution of α chains of type Ⅳ collagen be a diagnostic marker of Alport′s syndrome and observation of α5α6 (Ⅳ) distribution by epidermal biopsy be useful for recognition of patients and carriers of Xlinked Alport′s syndrome.