STUDIES OF THE PATHOGENESIS OF GLOMERULOSCLEROSIS

大多数进展性肾小球疾病导致终末期肾脏疾病 系膜区细胞外基质(ECM)增多。 疾病中细胞外基质堆积的性质和速率的阐明 国家是理解和可能进行干预的先决条件 进行性肾小球硬化。全肾的变化 准备工作不能准确反映肾小球内的情况。为了这些 为什么我们开发了一种由显微解剖组成的技术 肾小球、原位逆转录和聚合酶链式反应。要量化类型的变化 IV型胶原基因的表达，我们建立了竞争性的聚合酶链式反应方法。我们 第一次检查了为肾癌进行的肾切除术，因为 这些患者中有50%患有肾小球硬化。我们发现`2IV 慢性阻塞性肺疾病患者胶原基因表达显著升高 肾小球硬化。细胞数量并没有平行增加， 这表明这种增加是由于alpha2IV上调所致。 胶原mRNA，而不是细胞增殖。正如我们在老鼠身上发现的那样， 肾小球`2IV胶原基因表达水平保持在较高水平，与 硬化程度，即使在广泛肾小球的患者中也是如此 伤痕累累。令人满意的是，我们拥有适当的工具来检查 在人类肾脏疾病的发病机制方面，我们开始了多中心研究 合作开发进步的标志。我们得到了两种基因中的一种 或诊断性肾活检中分离的肾小球。这个 最初的重点是糖尿病和IgA肾病。我们的 初步结果表明，α2/α3 IV型胶原 在正常肾脏中比率等于1，在糖尿病肾病中比率很高， 在膜性肾小球肾炎中为1。

Most progressive glomerular diseases leading to endstage renal disease have increased extracellular matrix (ECM) within mesangial areas. Elucidation of the nature and the rate of ECM accumulation in diseased states are prerequisites for understanding, and possibly interfering with, progressive glomerulosclerosis. Changes in whole kidney preparations do not accurately reflect those in glomeruli. For these reasons we developed a technique consisting of microdissection of glomeruli, in situ RT of mRNA, and PCR. To quantitate changes in type IV collagen mRNA expression, we developed a competitive PCR assay. We first examined nephrectomies performed for renal carcinoma, since nearly 50% of these patients have glomerulosclerosis. We found that `2IV collagen cDNA was significantly elevated in patients with glomerulosclerosis. There was not a parallel increase in cell number, suggesting that the increment was due to upregulation of alpha2IV collagen mRNA, rather than cellular proliferation. As we found in mice, glomerular `2IV collagen cDNA level remained high, independently of the degree of sclerosis, even in patients who had extensive glomerular scarring. Satisfied that we had the appropriate tools to examine the pathogenesis of renal disease in humans, we started a multi-center collaboration to develop markers of progression. We obtained either cDNA or isolated microdissected glomeruli from diagnostic renal biopsies. The initial focus is on diabetes mellitus and IgA nephropathy. Our preliminary results indicate that the alpha2/alpha3 type IV collagen ratio is equal to 1 in normal kidneys, is high in diabetic nephropathy, and is 1 in membranous glomerulonephritis.