大鼠ATG肾炎和人IgA肾病肾组织中ⅩⅧ型胶原的表达

目的观察ⅩⅧ型胶原在大鼠抗Thy-1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Thy-1血清制备大鼠ATG模型；Western blot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。     

大鼠ATG肾炎和人IgA肾病肾组织中XⅧ型胶原的表达

目的观察XⅧ型胶原在大鼠抗Thy-1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Thy-1血清制备大鼠ATG模型;Western blot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.     

膜性肾病合并IgA肾病的临床病理特点

目的探讨膜性肾病合并IgA肾病的临床病理特点。方法回顾性研究北京大学第一医院肾内科和北京大学肾脏病研究所1998年1月—2006年4月问的肾活检病例9572例,对11例膜性肾病合并IgA肾病的临床病理特点进行分析,结合免疫电镜标记方法,对其病理诊断及发病机制进行探讨。结果11例患者以中年为发病高峰,平均年龄39．9岁,女性多于男性（男：女为1：2．9）,临床表现为蛋白尿,其中7例（63．6％）出现肾病综合征水平的蛋白尿,7例（63．6％）合并镜下血尿,肾功能均正常,除外了肝炎病毒感染、系统性红斑狼疮等继发性疾病。光镜下可见肾小球基底膜空泡变性和增厚,系膜细胞和基质轻度增生,2例可见少数肾小球伴有新月体形成。免疫荧光检查见IgG和c3颗粒样沿肾小球毛细血管壁沉积;IgA团块状在肾小球系膜区沉积。电镜检查可见肾小球上皮细胞下多数块状电子致密物沉积,系膜区可见团块状电子致密物沉积。免疫电镜标记结果显示,IgG定位于肾小球上皮细胞下的电子致密物,IgA定位于肾小球系膜区的电子致密物。结论膜性肾病合并IgA肾病兼具有膜性肾病和IgA肾病的临床病理特点,其发生过程可能为各自独立发生的两种疾病的叠加所致。     

肾小球系膜细胞增生与系膜硬化机制的初步探讨

我们应用细胞培养及免疫组化的方法，探讨了肾小球系膜细胞增生及系膜硬化的机制，并进而观察了它们在肾小球硬化听作用。结果显示：系膜细胞有自分泌功能，肿瘤坏死因子和血管内皮素可促进系膜细胞增生。大量增多的系膜基质不但含有Ⅳ型胶原，也有Ⅲ型胶原。系膜细胞增生，系膜基质增多最终导致肾小球硬化。     

纤维样肾小球病1例报道及文献复习

目的 探讨纤维样肾小球病的病理形态特点.方法 观察1例纤维样肾小球病肾穿活检组织的病理形态(光镜、特殊染色、免疫组化、电镜)及临床资料分析,并结合文献讨论.结果 光镜下系膜增生、PAM-Masson染色系膜区见团块状状嗜复红蛋白沉积,GBM增厚、局灶节段细小钉突化;各种免疫球蛋白及补体在肾小球内不同程度的沉积;电镜见系膜区、GBM及肾小管基膜上沉积物中均见大量纤维样物质沉积,此类物质无分支,杂乱排列,较淀粉丝粗,较胶原纤维细.结论 纤维样肾小球病主要表现为膜性肾病型,其次为系膜增生型;超微结构观察是诊断纤维样肾小球病的主要依据,电镜下纤维样物质(直径15~25 nm)呈弥漫性或团块状分布于肾小球系膜区和(或)GBM是纤维样肾小球病的主要特点,患者多为中年女性,预后差.     

细胞外基质在人系膜增生性肾小球肾炎病变中的变化

肾小球细胞外基质（尤其系膜基质）的过量聚积是肾小球硬化的主要变化之一。我们应用免疫酶标技术及计算机图像分析系统，检测了系膜增生性肾小球肾炎病变过程中细胞外基质的变化。结果表明：增生扩张的系膜基质中含有Ⅳ型胶原，层粘连蛋白等多种正常肾小球细胞外基质成分，并随病变进展明显增加。Ⅲ型胶原在中，重度系膜增生性肾小球肾炎时也出现于增多的系膜基质中，说明正常时不存在于肾小球的间质胶原在肾小球过程中也起重要作用     

L-精氨酸对人肾系膜细胞胞外基质产生的影响

目的:探讨L-精氨酸(L-arg)对人肾系膜细胞胞外基质产生的影响及其作用机制。方法:运用放射免疫分析技术及羟-脯氨酸比色法分别检测L-arg作用后系膜细胞上清液中Ⅲ型前胶原与总胶原含量;运用RT-PCR技术检测L-arg对人肾系膜细胞Ⅳ型胶原基因表达的影响。结果:L-arg抑制Ⅲ型前胶原产生,抑制总胶原分泌,并抑制Ⅳ型胶原基因表达。结论:L-arg抑制人肾系膜细胞胞外基质产生,并可能与抑制胶原成分的基因转录有关。     

Ⅳ型胶原和Laminin在几种常见肾小球肾炎中的变化

Ⅳ型胶原在基膜中形成具有三维空间结构的胶原网，对毛细血管壁起支撑作用，缓解毛细血管内血压对管壁的压迫，并为基膜内其他成分提供组合支架。Ｌａｍｉｎｉｎ在基膜中借短臂与Ⅳ型胶原结合，借长臂与硫酸肝素多糖蛋白结合，共同维持基底膜的通透性。在肾小球肾炎病变过程中，Ⅳ型胶原和Ｌａｍｉｎｉｎ在系膜和基膜中的含量与分布发生改变。     

人胚胎肾小体系膜细胞的发育

对２８例（８￣２８周）人胚胎肾小体的系膜细胞进行光镜和电镜观察。结果表明：原始期肾小体内无系膜细胞，发育期肾小体系膜细胞形成，成熟期肾小体系膜细胞数量增多。胚胎系膜细胞可能来源于原始期肾小体的间充质细胞。系膜细胞具有丰富的粗面内质网，游离核糖体以及大小不等的溶酶体和吞噬体，在胚胎期具有合成系膜基质，参与基膜形成和维护滤过膜通透性的功能，并对毛细血管起支持作用。文内描述了系膜细胞的形态结构并对其功能     

重链沉积性肾病1例并文献复习

目的探讨重链沉积性肾病(heavy chain deposition ne-phropathy,HCDN)的临床病理学特征及诊断。方法对1例HCDN肾脏穿刺活检组织进行光镜、免疫组化及透射电镜检查,并复习相关文献。结果光镜:弥漫结节性肾小球硬化症伴膜增殖(Ⅰ型)。免疫表型:IgG、C3d在肾小球系膜大量均匀沉积,沿肾小球毛细血管襻、Bowman囊和肾小管基膜呈线性沉积;淀粉样P蛋白系膜区和血管襻不规则少量沉积;IgA、IgM、Igκ、Igλ、C1q和淀粉样A蛋白均阴性。电镜:肾小球系膜区中等量致密物沉积,肾小球毛细血管内皮下、肾小管基膜外侧及小血管壁高电子致密物线性沉积。结论弥漫结节性肾小球硬化是HCDN典型的组织学改变,确诊需结合免疫球蛋白轻链(light chain,LC)和重链(heavy chain,HC)的免疫表型及电镜检查。     

Mesangial deposition of type I collagen in human glomerulosclerosis

The presence of type I collagen in both diffuse and nodular diabetic glomerular lesions has been examined using immunohistochemical and electron microscopic techniques. At the ultrastructural level, banded collagen fibrils were observed in the mesangium in all cases of nodular (Kimmelstiel-Wilson) sclerosis and in 60% of the diffuse sclerotic lesions. Antibodies against type I collagen were localized in the fibrotic interstitium and the mesangium in all cases examined. Staining with type I collagen antibodies occurred in glomeruli with intact Bowman's capsules, and was predominantly localized to areas immediately adjacent to mesangial cells. In cases of focal sclerosis of nondiabetic origin, banded collagen fibrils and staining with anti-type I collagen antibody were observed in all cases in which the segmental lesion was presented in the specimen. The pattern of antibody localization in both the diabetic lesions and focal sclerosis differed from that obtained using anti-type IV (basement membrane) collagen antibodies. These results demonstrate that type I collagen is among the extracellular matrix components that comprise the sclerotic glomerular lesions of both diabetic and nondiabetic origin. Furthermore, the spatial localization of this collagen type suggests mesangial cell origin.     

Distribution of type I collagen in human kidney diseases in comparison with type III collagen

The distribution of type I collagen in normal and diseased renal tissues was studied using immunofluorescence and immunoelectron microscopy, and was compared with that of type III collagen. In normal human kidneys, a monoclonal antibody against type I or type III collagen reacted with the renal interstitium, but not with the intra-glomerular structures. In various types of glomerulonephritis, immunofluorescent staining for type I collagen was positive in the fibrocellular and fibrous crescents, sclerosed glomeruli, and infrequently within the glomerular mesangium. In the crescents and sclerosed glomeruli, type I collagen was co-localized with type III collagen. The staining intensity of type I collagen in those areas was generally stronger than that in the interstitium. Mesangial staining for type I collagen was present within the glomeruli, particularly with a marked mesangial matrix increase, but was less in amount and frequency compared with type III collagen staining. These findings indicate that the fibrosclerotic process in damaged glomeruli is accompanied by the appearance of interstitial collagens, and that participation of type I collagen is prominent in crescent organization and global glomerular sclerosis, but is less frequent in mesangial expansion, compared with type III collagen.     

Collagenofibrotic glomerulopathy with a widespread expression of type-V collagen

Collagenofibrotic glomerulopathy is considered as a form of glomerulopathy in which organized collagen type III progressively deposits. We report a case of this disease with widespread expression of collagen type V. A 65-year-old woman was admitted to our hospital for further evaluation of nephrotic-range proteinuria. The patient had had anemia and hypertension for 9 years, and proteinuria for 3 years. A renal biopsy specimen showed a remarkable mesangial expansion with Congo red-negative and periodic acid-Schiff-positive deposits. At the ultrastructural level, two forms of bundling fibers were found in the mesangium and subendothelial side of the glomerular basement membranes (GBM). The GBM itself appeared normal. Immunohistochemical investigation showed that the glomerular lesions were strongly reactive with both anti-collagen type-III and -V antibodies. Immunoelectron microscopy demonstrated collagen type V in both forms of bundling fibers. Despite therapy, her renal function declined. The clinical course and renal pathology of this case were in accordance with collagenofibrotic glomerulopathy except for the widespread expression of collagen type V. Collagen type V is a fibrillar collagen capable of forming banding fibrils. This report poses the question whether collagen type V accumulates only in this particular case or whether it is a normal component in collagenofibrotic glomerulopathy.     

Alterations in extracellular matrix components in transplant glomerulopathy

The distribution pattern of extracellular matrix (ECM) components in transplant glomerulopathy was studied in relation to light microscopic features, actin expression of mesangial cells, and intraglomerular inflammatory cells. Nine cases of mild (group I) and nine cases of severe (group II) transplant glomerulopathy were stained with antisera against fibronectin (FN), tenascin (TN), collagen types III and IV, smooth muscle actin, CD45RO, CD68, and Ki-67 antigen. The composition of ECM was similar in the two groups. The expanded mesangium was diffusely stained by type-IV collagen, FN and TN, and focally and weakly stained by type-III collagen and smooth muscle actin. Type-IV collagen was linearly stained along the capillary walls, imparting a double-contour feature, whereas FN and TN showed granular staining along the capillary walls. CD68 positive cells were increased in severe transplant glomerulopathy, but this increase was not related to ECM deposition. These findings suggest that increased glomerular deposition of normal and abnormal ECM components participate in the evolution of transplant glomerulopathy. Received: 5 October 1999 / Accepted: 17 January 2000     

Alterations in the extracellular matrix components in human glomerular diseases

Summary We investigated the distribution of extracellular matrix components such as fibronectin, laminin, type III, IV, V, and VI collagens and heparan sulfate proteoglycan (HSPG) in normal and diseased glomeruli using the indirect immunofluorescence method. This study included 96 renal biopsies: 7 controls, 3 minimal change nephrotic syndrome (MCNS), 47 mesangial proliferative glomerulonephritis (PGN), 25 membranous nephropathy (MN) and 14 membranoproliferative glomerulonephritis (MPGN) including 3 lupus nephritis. Fibronectin was detected predominantly in the mesangium and less prominently in the glomerular basement membrane (GBM) of normal glomeruli. Laminin and type IV collagen were present in the mesangium and GBM, type III collagen in the interstitium, and type V collagen in the mesangium, interstitium and a part of GBM. Type VI collagen was observed in the mesangium, interstitium and slightly in GBM. Anti-HSPG antibody reacted with the mesangium and GBM. MCNS showed a distribution of these antigens similar to that in normal controls. The finding that staining for HSPG was not decreased in the GBM and mesangium indicated that there was no change in the core protein of HSPG. Fibronectin, laminin, type IV collagen and HSPG were increased in the thickened GBM of MN and in the expanded mesangium of PGN. In MPGN, these matrix components were increased in the mesangium and GBM with remarkable increase of type V and VI collagens. While type III collagen was not found in normal glomeruli, it became detectable in the mesangium and a part of GBM in MPGN. No significant decrease in the intensity of fluorescence for HSPG was observed in the glomeruli from nephrotic patients.These findings suggest that proteinuria might be caused by the structural alteration in the glycosaminoglycan portion of HSPG, changes in any anionic material other than HSPG, or both, and also indicate that the glomerular mesangial sclerosis is closely related to the increase of type V and VI collagens.     

Immunohistochemical localization of extracellular matrix components in human diabetic glomerular lesions.

The immunohistochemical localization of the extracellular matrix was examined in 31 cases with different degrees of human diabetic nephropathy using antisera to human collagen types I, III, IV, V, fibronectin, laminin, and basement-membrane-associated heparan sulfate proteoglycan (HSPG). In normal glomeruli, HSPG was predominantly localized in the glomerular basement membrane and in the mesangium, and to minor extent in the basement membranes of tubules and Bowman's capsule. Collagen IV and laminin were distributed in glomerular basement membrane and mesangium in minor amounts. Interstitial collagens usually do not occur within glomeruli except for collagen V which has a light microscopic glomerular distribution similar to collagen IV. In diabetic diffuse glomerulosclerosis, the enlarged mesangial matrix showed an increased staining reaction for collagen IV, V, laminin, and fibronectin whereas the staining pattern of HSPG was markedly reduced. Early, small nodular lesions in diabetic glomeruli were similarly positive for most of the basement membrane components, whereas HSPG remained absent. With an increase in the diameter of the noduli, however, the staining reaction for all basement membrane components diminished, whereas interstitial collagens V and III, but not collagen I, were present in these noduli in substantial amounts. These initial studies provide evidence that the changes in the glomerular matrix in diabetic nephropathy may be divided into distinct and progressing stages of lesions. The reduced amount of HSPG even in slight, early lesions may represent the morphologic correlate to the impaired filter function of the glomerular basement membrane.     

The development of an acth-induced renal glomerular lesion in Mus musculus. An ultrastructural study

Male house mice (Mus musculus) were injected with 4 international units of ACTH daily for 1, 2, 3 and 4 weeks and with four units daily for four weeks followed by 8 units for 8 days. Light microscopy of kidneys showed a glomerular lesion characterised by the expansion of the mesangium, deposition of PAS positive material in the glomerular mesangium and extraglomerular mesangium hypertrophy of juxtaglomerular cells and a successive increase in oil red-O staining material in the glomerulus. Electron microscopy revealed the progressive accumulation in the mesangial matrix of three morphologically distinct forms of deposits: amorphous, globular and particulate. The accumulation of amorphous deposit apparently is partially responsible for the increased PAS positive staining of the mesangium. Globular (and possibly particulate) deposit probably corresponds to the oil red-O positive material. The evidence suggests that the deposits are extraglomerular in origin, but their chemical nature is unknown.     

In situ localization of type III and type IV collagen-expressing cells in human diabetic nephropathy

Nodular intercapillary glomerulosclerosis is the most typical lesion of diabetic nephropathy (DN) and is characterized by increased extracellular matrix (ECM) and amorphous masses of mesangial matrix. The local exaggeration of these deposits results in the formation in the typical diabetic nodule. To clarify the composition of the ECM of sclerotic lesions in DN, we investigated the distribution of type III and type IV collagens and their mRNAs by immunohistochemistry and in situ hybridization, respectively. In normal renal tissues, there was no intraglomerular immunostaining for type III collagen, while strongly positive staining was found in the extraglomerular interstitum. Positive immunostaining for type IV collagen was also present in the mesangium, glomerular basement membrane (GBM), Bowman's capsule, and the vascular pole of the normal glomerulus. In DN, the nodular lesions were negative for type III collagen and strongly positive for type IV collagen. On the other hand, in the late stage of global sclerosis, both type III and type IV collagens were diffusely present in the sclerotic matrix. To determine the origins of these type III and type IV collagens in the sclerotic matrix, in situ hybridization was performed, utilizing thymine-thymine (T-T) dimerized synthetic oligonucleotides complementary to either proα(III) chain or pro α1 (IV) chain mRNAs as probes. The signals were detected by enzyme immunohistochemistry using an anti-T-T antibody. Intraglomerular cells (glomerular epithelial and mesangil cells) containing type III collagen mRNA were found in DN with sclerotic lesions, but not in normal glomeruli. At this stage of sclerosis, intraglomerular cells (mainly glomerular epithelial cells and infrequently mesangial cells) were positive for type IV collagen mRNA, but there were few positive cells in globally sclerotic glomeruli. This study provides evidence that both type III and type IV collagens are synthesized by intraglomerular cells during sclerosis and become significant constituents of the sclerotic matrix in DN.     

Familial lobular glomerulopathy

A family with an unusual lobular glomerulopathy is described. Renal tissue from three males and one female in two successive generations was available for review. The glomerulopathy was characterized by a marked lobular accentuation with only a modest increase in mesangial cellularity. Immunofluorescence in two patients showed focal or diffuse staining with immunoglobulins G, A, M, and C3 in the mesangium and along the glomerular capillary basement membranes. Ultrastructural study showed amorphous granular subendothelial material distending capillary loops and mesangial regions. This material accounted for the pronounced lobular accentuation. The patients in this family presented with proteinuria, hematuria, and hypertension. Three of the four patients have sustained cerebral vascular accidents and two have died. This family is compared with a previously reported family that showed similar glomerular pathology.     

Significance of fibrils in the formation of the Kimmelstiel-Wilson nodule

Summary The pathogenesis of the nodular lesion in diabetic glomerulosclerosis is described in association with fibrils. Thirteen diabetic patients with glomerular nodular lesions and 9 diabetics without the nodules were examined by electron microscopy using periodic acid-thio-carbohydrazide-silver proteinate staining. In cases of nodular glomerulosclerosis, abundant fibrillar structures mixed with electron-dense material were detected within the nodule and the mesangial matrix. They were also occasionally observed along the subendothelial space of the glomerular capillary walls. On the cross-section, these fibrils, including the lucent periphery, were 34 nm wide. Immunohistologically, collagen V and collagen VI were detected in nodular lesions. In contrast, in cases of the diffuse type of glomerulosclerosis, the widened mesangium was composed of dense material, which resembled the original mesangial matrix. The above fibrils were not detected in the mesangium. These findings suggest that the accumulation of the peculiar fibrils in the glomerular mesangium is a major pathogenic factor in the formation of Kimmelstiel-Wilson nodules.