大鼠ATG肾炎和人IgA肾病肾组织中XⅧ型胶原的表达

Collagen type XⅧ expression in renal tissue of rat anti-Thy-1 glomerulonephritis and human IgA nephropathy

目的观察XⅧ型胶原在大鼠抗Thy1系膜增生性肾小球肾炎(ATG)模型和人IgA肾病肾组织中表达,探讨XⅧ型胶原在肾小球肾炎及肾脏硬化中的作用。方法尾静脉注射兔抗Thy1血清制备大鼠ATG模型;Westernblot检测大鼠ATG肾皮质组织中XⅧ型胶原、Ⅳ型胶原蛋白的表达变化;原位杂交确定XⅧ型胶原mRNA在ATG大鼠肾脏中的细胞定位;免疫组化ABC法观察XⅧ型胶原蛋白在人IgA肾病肾组织的分布,并对其染色强度作定量分析。结果大鼠ATG模型中随着病变的进展肾皮质组织中XⅧ型胶原、Ⅳ型胶原蛋白的表达都呈先持续增加而后回落的趋势;原位杂交显示XⅧ型胶原mRNA在ATG大鼠肾组织中的表达细胞呈多样性;免疫组化结果证实XⅧ型胶原是一种基膜胶原蛋白,在人IgA肾病的细胞外基质沉积中表达显著增加。结论XⅧ型胶原是一种基膜成分,肾脏内多种细胞均可表达XⅧ型胶原,其分布与Ⅳ型胶原相似。

Purpose To observe the expression and distribution of collagen type ⅩⅧ in renal tissue of rat anti-Thy-1 mesangioproliferative glomerulonephritis and human IgA nephropathy, and to explore its significance in the development of glomerulonephritis as well as glomerulosclerosis. Methods A rat ATG model was established by tail intravenous injection with rabbit anti-Thy-1 serum. Expression of collagen types ⅩⅧ and Ⅳ was detected with Western blot. In situ hybridization was used to detect cells that can express collagen type ⅩⅧ. Immunohistochemistry with image analysis system was performed to determine the positive staining areas of collagen type ⅩⅧ in IgA nephropathy. Results In the rat ATG model, the protein expression of collagen types ⅩⅧ and Ⅳ displayed a similar trend that gradually increased and then decreased. In situ hybridization showed that many types of cells could express collagen type ⅩⅧ mRNA in kidney. Immunohistochemistry demonstrated that collagen type ⅩⅧ was a component of basement membrane and its expression notably increased in ECM deposition of human IgA nephropathy. Conclusions Collagen type ⅩⅧ is located in basement membrane, which can be expressed by many types of cells in kidney and presents a similar distribution with collagen type Ⅳ.