A case of cutaneous collagenous vasculopathy / 中华皮肤科杂志

A 22-year-old female patient presented with skin flushing in the bilateral legs for 4 years, which gradually spread throughout the whole lower limbs and forearms 6 months ago. Skin examination showed diffuse flushing and dilated capillaries in the lower limbs and both forearms, and the flushing faded after a press. Histopathological examination of the skin lesion on the leg showed hyperkeratosis in a basket-like shape, increased pigmentation in the basal layer, infiltration of the superficial dermis with scattered lymphocytes, with no obvious red blood cell overflow; periodic acid-Schiff staining showed thickened and homogeneous deposits around the blood vessels; immunohistochemical staining showed thickened blood vessel walls and positive staining for type Ⅳ collagen. Diagnosis: cutaneous collagenous vasculopathy.

Distribuição ultraestrutural de colágeno tipo IV em feridas experimentais após tratamento com papaína / Ultrastructural distribution of type IV collagen in experimental wounds after treatment with papaine

RESUMO: Modelo do estudo: Experimental. Objetivo: Investigar a distribuição de fibras colágeno tipo IV, por microscopia eletrônica de transmissão, em feridas experimentais tratadas com soluções de papaína. Metodologia: Ratos Wistar (n=18), machos, adultos, foram submetidos a procedimento cirúrgico para a retirada de seção quadrada de pele da região cervical, e posteriormente separados em dois grupos: Grupo I (n = 9), sem tratamento; e Grupo II (n = 9), tratado com soluções de papaína a 10% (até o 7º dia), 6% (do 8º ao 14º dia) e 4% (do 15º ao 21º dia). Todos os animais foram sacrificados com 7, 14 e 21 dias, e as áreas lesadas retiradas, lavadas em PBS e fixadas em 2,5% de glutaraldeo, 4% de formaldeio recém preparado, em solução tamponada contendo 60 mM Pipes, 20 mM Hepes, 10 mM etilenoglicol-bis- (B-aminoetiléter) - Ácido N, N, N'-tetraacético, KCl 70 mM e MgCl2 5 mM pH 7,2 por 1h; pós-fixadas em solução contendo tetróxido de ósmio a 1%, ferrocianeto a 0,8% e cloreto de cálcio a 5 mM; desidratados em acetona graduada e embebidos em Epon® para confecção de secções finas, coradas com acetato de uranilo e citrato de chumbo, e examinadas em microscópio electrônico de transmissão Zeiss LEO EM 906 (TEM). Resultados: A distribuição das fibras colágeno tipo IV das lesões tratadas com papaína (Grupo II), com 14 e 21 dias, mostraram-se mais organizadas que as fibras do Grupo I. Conclusões: A papaína mostrou-se um importante facilitador para a organização de fibras colágeno tipo IV em feridas experimentais. (AU)

ABSTRACT Study model: Experimental. Objective: Investigate the distribution of type IV collagen fibers by transmission electron microscopy, in experimental wounds treated with papaine solutions. Methodology: Adult male Wistar rats (n = 18) underwent a surgical procedure to remove a square section of skin from the cervical region, and then separated into two groups: Group I (n = 9), without treatment; and Group II (n = 9), treated with papain solutions of 10% (up to the 7th day), 6% (from the 8th to the 14th day) and 4% (from the 15th to the 21st day). All animals were sacrificed at 7, 14 and 21 days, and the injured areas removed, washed in PBS, and fixed in 2.5% glutaraldehyde, 4% freshly prepared formaldehyde in buffered solution containing 60 mM Pipes, 20 mM Hepes, 10 mM ethyleneglycol-bis- (B-aminoethylether) -N, N, N'-tetraacetic acid, 70 mM KCl, and 5 mM MgCl 2 pH 7.2 for 1h; post-fixed in solution containing 1% osmium tethoxide, 0.8% ferrocyanide, and 5 mM calcium chloride; dehy-drated in graduated acetone and soaked in Epon® to make thin sections stained with uranyl acetate and lead citrate and examined under a Zeiss LEO EM 906 (TEM) transmission electron microscope. Results: The distribution of type IV collagen fibers from papaine-treated lesions (Group II) at 14 and 21 days was more organized than Group I fibers. Conclusions: Papaine has proven to be an important facilitator for the organization of type IV collagen fibers in experimental wounds. (AU)

Cutaneous collagenous vasculopathy: light and transmission electron microscopy

Abstract Cutaneous collagenous vasculopathy is a rare acquired idiopathic microangiopathy characterized by progressive development of diffuse asymptomatic telangiectasias and histologically by accumulation of collagen type IV around the affected vessels. It is diagnosed by its clinical history, confirmed by light microscopy with collagen-specific immunostaining. We report a case of a patient with extensive acquired telangiectasias on the left arm, clinically resembling unilateral nevoid telangiectasia. Dilated blood vessels with thickened walls were observed in the dermis. Immunohistochemistry with collagen IV antibodies revealed marked collagen deposition around the vessels, confirming the diagnosis. Transmission electron microscopy observed duplicate and triplicate vascular basal membrane associated with deposition of amorphous material around the membranes.

De novo mutations in COL4A5 identified by whole exome sequencing in 2 girls with Alport syndrome in Korea / 소아과

Alport syndrome (ATS) is an inherited glomerular disease caused by mutations in one of the type IV collagen novel chains (α3, α4, and α5). ATS is characterized by persistent microscopic hematuria that starts during infancy, eventually leading to either progressive nephritis or end-stage renal disease. There are 3 known genetic forms of ATS, namely X-linked ATS, autosomal recessive ATS, and autosomal dominant ATS. About 80% of patients with ATS have X-linked ATS, which is caused by mutations in the type IV collagen α5 chain gene, COL4A5. Although an 80% mutation detection rate is observed in men with X-linked ATS, some difficulties do exist in the genetic diagnosis of ATS. Most mutations are point mutations without hotspots in the COL4A3, COL4A4, and COL4A5 genes. Further, there are insufficient data on the detection of COL4A3 and COL4A4 mutations for their comparison between patients with autosomal recessive or dominant ATS. Therefore, diagnosis of ATS in female patients with no apparent family history can be challenging. Therefore, in this study, we used whole-exome sequencing (WES) to identify mutations in type IV collagen in 2 girls with glomerular basement membrane structural changes suspected to be associated with ATS; these patients had no relevant family history. Our results revealed de novo c.4688G>A (p.Arg1563Gln) and c.2714G>A (p.Gly905Asp) mutations in COL4A5. Therefore, we suggest that WES is an effective approach to obtain genetic information in ATS, particularly in female patients without a relevant family history, to detect unexpected DNA variations.

Endoplasmic reticulum stress and proteasome pathway involvement in human podocyte injury with a truncated COL4A3 mutation / 中华医学杂志(英文版)

Background@#Collagen type IV (COL4)-related nephropathy includes a variety of kidney diseases that occur with or without extra-renal manifestations caused by COL4A3-5 mutations. Previous studies revealed several novel mutations, including three COL4A3 missense mutations (G619R, G801R, and C1616Y) and the COL4A3 chr:228172489delA c.4317delA p.Thr1440ProfsX87 frameshift mutation that resulted in a truncated NC1 domain (hereafter named COL4A3 c.4317delA); however, the mutation mechanisms that lead to podocyte injury remain unclear. This study aimed to further explore the mutation mechanisms that lead to podocyte injury.@*Methods@#Wild-type (WT) and four mutant COL4A3 segments were constructed into a lentiviral plasmid, then stably transfected into human podocytes. Real-time polymerase chain reaction and Western blotting were applied to detect endoplasmic reticulum stress (ERS)- and apoptosis-related mRNA and protein levels. Then, human podocytes were treated with MG132 (a proteasome inhibitor) and brefeldin A (a transport protein inhibitor). The human podocyte findings were verified by the establishment of a mus-Col4a3 knockout mouse monoclonal podocyte using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) technology.@*Results@#Our data showed that COL4A3 mRNA was significantly overexpressed in the lentivirus stably transfected podocytes. Moreover, the COL4A3 protein level was significantly increased in all groups except the COL4A3 c.4317delA group. Compared to the other test groups, the COL4A3 c.4317delA group showed excessive ERS and apoptosis. Podocytes treated with MG132 showed remarkably increased intra-cellular expression of the COL4A3 c.4317delA mutation. MG132 intervention improved higher ERS and apoptosis levels in the COL4A3 c.4317delA group. Mouse monoclonal podocytes with COL4A3 chr:82717932insA c.4852insA p.Arg1618ThrfsX4 were successfully acquired; this NC1-truncated mutation suggested a higher level of ERS and relatively remarkable level of apoptosis compared to that of the WT group.@*Conclusions@#We demonstrated that excessive ERS and ERS-induced apoptosis were involved in the podocyte injury caused by the NC1-truncated COL4A3 mutation. Furthermore, proteasome pathway intervention might become a potential treatment for collagen type IV-related nephropathy caused by a severely truncated COL4A3 mutation.

Expression of matrix metalloproteinase-9, tissue inhibitor of metallopro-teinase-1 and collagen type Ⅳ in lung of rats with multiple organ dysfunc-tion syndrome / 中国病理生理杂志

AIM:To determine the expression of matrix metalloproteinase-9(MMP-9),tissue inhibitor of me-talloproteinase-1(TIMP-1)and collagen type Ⅳ(Ⅳ-C)in the lung of rats with multiple organ dysfunction syndrome(MODS)and to investigate the mechanism of lung injury in MODS.METHODS:Adult male Sprague-Dawley(SD)rats(n=40)were randomly divided into sham control group and cecal ligation and puncture(CLP)model group.The rats in CLP group were divided into 4 subgroups as different intervals(6 h,12 h,24 h and 48 h),and there were 8 rats in each group.The rat model of MODS was established by CLP.All rats were sacrificed at various intervals.The functions of the liver,kidney and lung were determined by blood biochemical and blood gas analysis.The morphological changes of the lung tissues were observed with HE staining.The serum levels of tumor necrosis factor(TNF)-α,interleukin(IL)-1β,MMP-9 and TIMP-1 were measured by ELISA.The expression of MMP-9 and TIMP-1 in the lung tissues was detected by RT-PCR and immunohistochemistry ,and the expression of Ⅳ-C in the lung tissues was detected by immunofluorescence and Western blot.RESULTS:Compared with sham control group ,the functions of the liver ,kidney and lung were damaged at different degrees in model groups.No histopathological change in the lung tissues of sham control group was found ,and the lung injury was serious in model groups.Compared with sham control group ,the serum levels of TNF-α,IL-1β,MMP-9 and TIMP-1 in model groups increased significantly(P<0.05)and peaked at the interval of 12 ～24 h after modeling(P<0.01).The expression of MMP-9 and TIMP-1 in the lung tissues of model groups increased ,and peaked at 12 and 24 h,respectively(P<0.01).The protein level of Ⅳ-C in MODS 6 h group was not changed as compared with control group,while that at the interval of 12～48 h after modeling was significantly decreased and dropped to the lowest at 24 h(P<0.01).CONCLUSION:MMP-9 and TIMP-1 play important roles in lung injury of MODS rats by regulating the syn-thesis and decomposition of IV-C which is the main component of extracellular matrix.

Collagen IV and laminin expression in squamous cellcarcinomas of lower lip and tongue / Expressão de colágeno IV e laminina em carcinomas de células escamosas de lábio inferior e língua

In this study, the expression of extra cellular matrix proteins was immunohisto chemically studied and compared with the histological grading of squamous cell carcinomas of the lower lip and tongue. Material and Methods: The lower lip carcinomas (n =12) and the tongue carcinomas (n = 12) were histopathologically graded according to Bryne’smethod. The immunohisto chemical technique used specific antibodies for collagen IV and laminin. Histopathological and immunohisto chemical analysis were carried-out at the invasive tumor front. Results: Most of the lower lip carcinomas(91.7%) were classified with lower scores and all tongue carcinomas (100%) with high-grade malignant scores (p < 0.01). Collagen type IV expression was absent in the peri tumoral basement membrane in 50% of lower lip carcinomas and in66. 7% of tongue carcinomas (p = 0.09). Laminin expression was absent in the peritumoral basement membrane in 66.7% of lower lip carcinomas and in 58.3% of tongue carcinomas (p = 0.48). When these two glycoproteins were expressed, they showed alinear, thin and discontinuous pattern and a weak intensity of expression. Conclusion: The high gradem alignancy score of the tongue carcinomas was associated with the pattern of expression of the matrix proteins studied. This suggested that tonguesquamous cell carcinomas have more invasive potential and more aggressive biological behaviorthan the lower lip carcinomas...

Neste estudo, a expressão das proteínas da matriz extracelular foi estuda da imunoisto quimicamente e comparada com a classificação histológica dos carcinomas de células escamosas do lábio inferior e língua. Material e Métodos: Os carcinomas de lábio inferior (n = 12)e os carcinomas de língua (n = 12) foram graduados histopatologicamente de acordo com o método de Bryne. A técnica de imunoistoquímica utilizou anticorpos específicos para colágeno IV e laminina. Análises histopatológica e imunoistoquímica foram conduzidas na frente invasiva tumoral. Resultados: A maioria dos carcinomas de lábio inferior (91,7%) foi classificada em baixo grau e todos os carcinomas de língua (100%) em alto grau de malignidade (p < 0,01). A expressão de colágeno tipo IV estava ausente na membrana basal peri tumoral em 50% dos carcinomas de lábio inferior e em 66,7% dos carcinomas de língua (p = 0,09). A expressão de laminina estava ausente na membrana basal peri tumoral em 66,7%dos carcinomas do lábio inferior e em 58,3% dos carcinomas de língua (p = 0,48). Quando estas duas glicoproteínas foram expressas, mostraram-se comum padrão linear, fino e descontínuo e uma fraca intensidade de expressão. Conclusão: O alto grau de malignidade dos carcinomas de língua associou-se com o padrão de expressão das proteínas de matriz estudadas. Isso sugere que carcinomas de células escamosas de língua têm comportamento biológico mais agressivo e potencial mais invasivo do que os carcinomas de lábio inferior...

Role of STAT3 in the regulation of autophagy in the glomerular mesangial cells of diabetic nephropathy / 中华肾脏病杂志

Objective To observe the changes of STAT3 signaling transduction pathway and autophagy activity in human glomerular mesangial cells cultured in high glucose, as well as the effect of STAT3 on autophagy, exploring whether SAT3 further influence extracellular matrix proteins type IV collagen secretion through the regulation of autophagy. Methods Culture human renal mesangial cells under different conditions, STAT3 pathway was inhibited with specific blocking agent S3I?201 and siRNA respectively. The experiment was divided into: (1) Control group: normal glucose concentration; (2) High glucose group: divided into 12 h, 24 h, 48 h, 72 h incubation group. (3) High glucose+S3I?201 group: pretreated cells with 30 μmol/L S3I?201 (Selleck S1155) for 1 h, then incubation with high glucose for another 24 hours. (4) High glucose+STAT3?siRNA group: siRNA transfection firstly, then incubation with high glucose for 24 hours. (5) High glucose+S3I?201+3?MA group: pretreated cells with 2 mmol/L 3?MA (Selleck S2767) and 30 μmol/L S3I?201 for 1 h, then incubation with high glucose for another 24 hours. Western blot was employed to detect the protein of STAT3, p?STAT3 and autophagy related protein LC3, p62 expressions. The changes of autophagosome quantity was observed with transmission electron microscope. The extracellular matrix protein collagen IV expression was measured with ELISA. Results Compared with the control group, glomerular mesangial cells cultured with high glucose for 24h, the expressions of STAT3 and p?STAT3 increased (P<0.01), while the expression of autophagy related proteins LC3II/LC3I decreased. The expression of p62 increased and the number of autophagosome reduced under transmission electron microscope, which all indicated the decrease of autophagy activity (P<0.05). Blocking STAT3 signaling pathway with S3I?201 and STAT3?siRNA respectively, compared with high glucose group, LC3II/LC3I was up?regulated and p62 was down?regulated, and the number of autophagosome was increased significantly, which all indicated the increase of autophagy activity (P<0.05). Extracellular matrix proteins collagen IV expression of cells cultured with high glucose was higher than the control group (P<0.05), and the application of S3I?201 blocking STAT3 pathway caused type IV collagen expression to decrease (P<0.05). The application of the autophagy inhibitor 3?MA could convert the result and lead to an increase of type IV collagen expression (P<0.01). Conclusions High glucose could active STAT3 signaling pathway of human renal mesangial cell and increase STAT3, p?STAT3 expression. High glucose could inhibit autophagy activity of human renal mesangial cells. Inhibition of STAT3 pathway activation may reduce the inhibitory effect of high glucose on autophagy of human renal mesangial cells. High glucose leads to an increase of type IV collagen secretion of human glomerular mesangial cells. The activation of STAT3 pathway may increase type IV collagen secretion through negative regulation of autophagy, which eventually leads to diabetic nephropathy.

Bullous pemphigoid in a 3-month-old infant: case report and literature review of this dermatosis in childhood / Penfigoide bolhoso em lactente de 3 meses: relato de caso e revisao de literatura da dermatose na infancia

Bullous pemphigoid is an autoimmune subepidermal blistering dermatosis that is uncommon in childhood. We report a case of a female infant, 3 months old, which presented clinical and laboratory data for the confirmatory diagnosis of bullous pemphigoid. The authors used immunohistochemical staining for collagen type IV that allowed the differentiation of bullous pemphigoid from other subepidermal bullous diseases. Opportunely we review the clinical, immunological, therapeutic and prognostic features of this pathology in children.

O penfigoide bolhoso é uma dermatose bolhosa autoimune subepidérmica, incomum na infância. Relatamos um caso de lactente feminina, com 3 meses de idade, que apresentou dados clínicos e laboratoriais confirmatórios para o diagnóstico de penfigoide bolhoso. Os autores utilizaram a coloração de imuno-histoquímica para o colágeno tipo IV que permitiu a diferenciação do penfigoide bolhoso de outras buloses subepidérmicas. Oportunamente, revisamos as características clínicas, imunológicas, terapêuticas e prognósticas da patologia na criança.

Effect of ligustrazine hydrochloride injection on TGF-β1-induced proliferation and type IV collagen secretion in human mesangial cells / 第二军医大学学报

Objective To observe the effect of ligustrazine hydrochioridc(LHC) injection on TGF-β1 -induced proliferation and type IV collagen secretion in the human mesangial cells(HMCs). Methods The interstitial fibrosis in kidney disease was mimicked by inducing proliferation and type IV collagen secretion in HMCs with TGF- β1. The experiment was divided into 5 groups: blank, control, low, medium, and high(10, 30, and 100 μg/ml)ligustrazinc hydrochloride groups. MTT method was adopted to examine the proliferation and inhibition rate of HMCs. Enzyme-linked immunosorbent assay was used to determine the production of type IV collagen in cultured HMCs. Results LHC at high concentration (100 μg/ml) significantly inhibited the proliferation of HMCs (P<0. 01). LHC also inhibited the production of type IV collagen, with the significant inhibition found when at the concentration of 100 μg/ml (P

Expressions of matrix metalloproteinase-9,IV collagen and CD34 in epithelial ovarian tumor and its significance / 中国医师进修杂志

Objective To explore the expression and significance of matrix metalloproteinase (MMP)-9, IV collagen and CD34 in epithelial ovarian tumor. Methods Eighty-two patients with epithelial ovarian tumor, among them,there were 48 malignant epithelial ovarian carcinomas, 23 borderline epithelial ovarian tumors and 11 benign epithelial ovarian tumors. The expression of MMP-9, IV collagen and CD34 were detected by immunohistochemistry. Results The expression of MMP-9 was strongly linked to the degree of malignant ovarian carcinomas (F= 39.306,P< 0.01). The expression of CD34 was also strongly linked to the degree of malignant ovarian carcinomas [benign epithelial ovarian tumors was (17.18±5.64)%,borderline epithelial ovarian tumors was (29.76±7.18)%,well-differentiated malignant epithelial ovarian carcinomas was (57.20±8.55)%,moderately-differentiated malignant epithelial ovarian carcinomas was (71.20±8.48)%, poorly-differentiated malignant epithelial ovarian carcinomas was(90.38±20.03)%](F= 100.072, P < 0.01). The expression of IV collagen in malignant epithelial ovarian carcinomas was different from that in borderline epithelial ovarian tumors and benign epithelial ovarian tumors (F = 11.554,P<0.0l). The expression of MMP-9 was positive correlation with the loss expression of IV collagen and the expression of CD34 (r=0.796,0.802,P< 0.01).Conclusions The positive expression of MMP-9,CD34 and the negative expression of IV collagen are obviously relevant to degree of malignant ovarian carcinomas.The combined testing on expression of MMP-9,CD34, IV collagen on ovarian carcinomas is significant to decide degree of malignant ovarian carcinomas and evaluate future development.

Effects of intrahepatic injection with hepatocyte growth factor and dexamethason on stereological quantitative changes of hepatic sinusoidal disease and expression of IV-collagen on hepatic sinusoidal walls / 中国基层医药

Objective To observe the effects of intrabepatic injection with bepatocyte growth factor and dexamethason on stereological quantitative changes of hepatic sinusoidal tissues and expression of IV-collagen on hepatic sinusoidal walls of patients with hepatic cirrhosis.Methods Under the guide of hypersound,98 cases of hepatic cirrhosis were intrahepatic injected with 80mg hepatocyte growth factor and 1mg dexamethason at one time,twice a week,12 times a course,pathological changes of hepatic sinusoidal tissues and the expression of IV-coliagen on hepatic sinusoidal walls were detected by liver biopsy after one course.Results Pathological changes of hepatic sinusoidal tissues were improved obviously(P＜0.01 ) and the expression of IV-collagen was alleviated significantly(P＜0.01 ) on 98cases of hepatic cirrhosis after one course.Conclusion Pathological changes of hepatic sinusoidal tissues and the expression of IV-collagen on hepatic sinusoidal wails can be improved obviously on patients with hepatic cirrhosis who had been intrahepatic injected with hepatocyte growth factor and dexamethason under the guide of hypersound.

Effect of high glucose on the role of fibronectin, collagen Ⅳ and platelet activating factor of mesangial cells / 中国医师杂志

promoted by high glucose, which can enlarge the biological effect of PAF.

Regulation of Type IV Collagen alpha Chains of Glomerular Epithelial Cells in Diabetic Conditions

An early feature of diabetic nephropathy is the alteration of the glomerular basement membrane (GBM), which may result in microalbuminuria, subsequent macroproteinuria, and eventual chronic renal failure. Although type IV collagen is the main component of thickened GBM in diabetic nephropathy, cellular metabolism of each alpha chains of type IV collagen has not been well studied. To investigate the regulation of alpha(IV) chains in diabetic conditions, we examined whether glucose and advanced glycosylation endproduct (AGE) regulate the metabolism of each alpha(IV) chains in the diabetic tissue and glomerular epithelial cells (GEpC). Glomerular collagen alpha3(IV) and alpha5(IV) chains protein were higher and more intense in immunofluorescence staining according to diabetic durations compared to controls. In vitro, mainly high glucose and partly AGE usually increased total collagen protein of GEpC by [3H]-proline incorporation assay and each alpha(IV) chain proteins including alpha1(IV), alpha3(IV), and alpha5(IV) in time-dependent and subchain-specific manners. However, the changes of each alpha(IV) chains mRNA expression was not well correlated to the those of each chain proteins. The present findings suggest that the metabolism of individual alpha(IV) chains of GBM is differentially regulated in diabetic conditions and those changes might be induced not only by transcriptional level but also by post-translational modifications.

Síndrome de Alport / Alport syndrome

El síndrome de Alport (SA) es una enfermedad hereditaria de las membranas basales, debida a mutaciones en la colágena tipo IV. Clínicamente se caracteriza por nefropatía hereditaria progresiva, comúnmente asociada a sordera sensorial y/o lesiones oculares y, en ocasiones, leiomiomatosis. Constituye de 1-2% de las causas de enfermedad renal terminal en Europa y aproximadamente 3% en la población pediátrica americana. Existen tres formas genéticas de SA: 1. Ligado al cromosoma X, debido a mutaciones en el gen COL4A5. Esta forma se presenta en aproximadamente 80-85% de los pacientes. 2. Autosómico recesivo, debido a mutaciones en ambos alelos (homocigotos) de los genes COL4A3 ó COL4A4, ubicado en el cromosoma 2q35-37. Se presenta aproximadamente en 15% de las familias. 3. Autosómico dominante, debido a una mutación heterocigota de los genes COL4A3 ó COL4A4. Se presenta aproximadamente en 5% de las familias. La evolución depende del género y de factores genéticos. Se expone la fisiopatología de la enfermedad desde el punto de vista genético y bioquímico, así como las manifestaciones clínicas e histopatológicas, estrategias de diagnóstico y las opciones terapéuticas.

Alport syndrome (AS) is a hereditary disease of basal membranes due to a mutation in type IV collagen. It is characterized by hereditary progressive nephropathy often associated with sensorineural hearing loss, ocular defects and less commonly leiomyomatosis. It accounts for 1-2% of end stage renal disease patients in Europe and approximately 3% of end stage renal disease children in America. There are 3 genetic forms of AS: 1. X-linked, due to mutation in COL4A5 gene, present in 80-85% of patients. 2. Autosomal recessive, due to mutations in both alleles of COL4A3 or COL4A4 located in the 2q35-37 chromosome, present in 15% of families with Alport syndrome. 3. Autosomal dominant, due to a heterozygous mutation in COL4A3 or COL4A6 genes, it is present in 5% of the patients. The disease genetics, biochemistry, clinical presentation, histopathology, diagnosis, prognosis and therapeutic options are reviewed.

Expressão imuno-histoquímica de colágeno IV, tenascina-C e fibronectina em lesões centrais e periféricas de células gigantes / Immunohistochemical expression of collagen IV, tenascin-C and fibronectinin central and peripheral giant cell lesions

Introdução - As lesões centrais e periféricas de células gigantes constituem um grupo de entidades patológicas que apesar de apresentarem características histopatológicas semelhantes, possuem etiologia e natureza incompletamente elucidadas. Material e Métodos - Procedeu-se análise imuno-histoquímica em 8 casos de lesões periféricas de células gigantes (LPCGs) e 16 casos de lesões centrais de células gigantes (LCCGs), obtidos dos arquivos do Serviço de Anatomia Patológica do Departamento de Odontologia da Universidade Federal do Rio Grande do Norte, quanto à expressão e distribuição das proteínas da matriz extracelular colágeno IV, tenascina-C e fibronectina. Resultados - A análise dos espécimes revelou expressão descontínua de colágeno IV na membrana basal subepitelial das LPCGs, comumente associadas às áreas de infiltrado inflamatório, bem como, em membrana basal perivascular de LPCGs e LCCGs, com padrão contínuo, diminuindo de intensidade da periferia para o centro das lesões. A tenascina-C exibiu imunorreatividade na matriz extracelular intersticial, nos padrões reticular e fibrilar, com distribuição predominantemente dispersa e não uniforme, nas lesões pesquisadas. A fibronectina demonstrou expressão imuno-histoquímica semelhante entre LPCGs e LCCGs, exibindo distribuição uniforme por toda a matriz extracelular intersticial, com padrão reticular e fibrilar, freqüentemente associados à presença de células gigantes multinucleadas e células mononucleadas. Conclusão - Os resultados obtidos não revelaram diferenças significativas na expressão imuno-histoquímica das proteínas, entre as lesões estudadas.

Introdution - The central and peripheral giant cells lesions represent a group of pathological entities that despite exhibiting similar histopatological features, etiology and nature are not entirely clear. Methods - It was performed an immunohistochemical analysis of 8 cases of peripheral giant cell lesion (PGCLs) and 16 cases of central giant cell lesion (CGCLs) obtained from the archives of Surgical Oral Pathology of Federal University of Rio Grande do Norte, in relation to expression and distribution of extracellular matrix proteins collagen IV, tenascin-C and fibronectin. Results - The specimens revealed discontinuous expression of collagen IV in epithelial basement membrane of PGCLs, commonly associated with areas showing inflammatory cells. Additionally, collagen IV was observed in vascular basal membrane of PGCLs and CGCLs, showing continuous pattern, fading from periphery to center areas. Tenascin-C expression was verified in extracellular matrix displaying reticular and fibrillar patterns and predominantly diffuse and heterogeneous distribution both in PGCLs and CGCLs. Immunohistochemical expression of fibronectin was observed equally in PGCLs and CGCLs, exhibiting a uniform distribution through extracellular matrix, with reticular and fibrillar patterns, mainly in the neighborhood of mononucleated and multinucleated cells. Conclusion - The results obtained demonstrated no significant differences in the pattern of expression of collagen IV, tenascin-C and fibronectin among PGCLs and CGCLs studied.

Tyrosine nitration site specificity identified by LC/MS in nitrite-modified collagen type IV

Non-enzymatic nitrite induced collagen cross-linking results in changes reminiscent of age-related damage and parallels the well-known model system, non-enzymatic glycation. We have recently observed that nitrite modification of basement membrane proteins can induce deleterious effects on overlying retinal pigment epithelial cells in studies relevant to age-related macular degeneration. The present work was undertaken in order to confirm 3-nitro-tyrosine (3-NT) as a product of the reaction and to identify the site specificity of nitration in collagen IV, a major component of basement membranes. Human collagen type IV was modified via incubation with 200 mM NaNO2 (pH=7.38) for one week at 37degrees C. The modified protein was prepared in 2 different ways, including acid hydrolysis and trypsin digestion for site specificity determination. The samples were analyzed by LC/MS using a C12 RP column. Site specificity was determined from tandem MS/MS data utilizing TurboSEQUEST software and the Swiss-Prot sequence database. 3-NT was detected in protein digests and acid hydrolysates of nitrite modified collagen IV. Positive identification with standard 3-NT was confirmed by identical Rt, lambda(max)=279 nm and 355 nm, and m/z=227. Analyses of tryptic digests identified four sites of tyrosine nitration, alpha1(IV)Y348, alpha1(IV)Y534, alpha2(IV)Y327, and alpha2(IV)Y1081. These sites are located in the triple-helical region of the protein and provide clues regarding potential sites for nitrite modification in collagen type IV.

An Immunoelectronmicroscopic Study on the Cellular Expression of Extracellular Matrix Components during Skin Regeneration after Damage in the Mouse / 대한해부학회지

To observe the cellular expression of extracellular matrix components during mouse skin regeneration, the wounded skin samples were processed by immunoelectronmicroscopic methods, using primary antibodies for fibronectin, collagen type IV and laminin. The tissues were observed under transmission electron-microscope. The results were summarized as follows. 1. The granulation tissues and x-cells were observed in the wound margin at 18 hr post injury. The number of fibroblasts was increased in the granulation tissues at 1 day post injury. 2. The expression of fibronectin was observed in x-cells at 18 hr post injury, and in fibroblasts at 1 day post injury. In x-cells, after 1 day post injury, the expression of fibronectin was decreased. 3. At 1 day post injury, the expression of collagen type IV was increased in fibroblasts whereas not in x-cells. 4. The expression of laminin was increased by 18 hr post injury, but decreased after 1 day post injury. On the basis of above findings, in mouse, the regenerations of wounded skin were faster than other animals. The first step, infiltration response, was processed till 18 hr or 1 day post injury. The second step, fibroblast proliferation phase, began at 1 day post injury. In the regenerations of wounded skin, x-cells migrated to the wound region and activated, earlier than fibroblast. Thereafter, x-cells which appeared to be transformed into fibroblasts, played an important role in the synthesis of fibronectin and collagen type IV, and the formation of granulation tissue, with migrated fibroblasts to the wound region.

Correlation of srum collagen type IV levels with histo-pathological findings assessed by liver biopsy in hepatitis B carrier with normal liver function test / 대한내과학회지

BACKGROUND: We compared the results of liver biopsy and the levels of serum type IV collagen of the hepatitis B carriers with normal liver function test (LFT) to evaluate the clinical usefulness of serum type IV collagen in predicting the progression of histopathological findings. METHODS : Thirty one chronic hepatitis B carriers with normal LFT and no significant clinical symptoms, who were Korean combat police, were classified into three groups according to their histologic results of the liver biopsies. The classification followed the standard proposed by Korean Society of Pathology. Blood samplings for serum type IVcollagen (reference : less than 5 ng/mL) were done in the morning of the same day of the liver biopsy. RESULTS: Of thirty one patients, thirteen patients showed normal histologic findings (41.9%, Group A), eleven patients revealed histologic abnormalities without fibrosis (35.5%, Group B) and seven patients were with fibrosis on liver biopsy (22.6%, Group C). Serum type IV collagen levels of Group A, B and C were 3.53 +/- .57 ng/mL, 3.56 +/- .17 ng/mL and 3.97 +/- .88 ng/mL, respectively. The average of serum type IV collagen levels of Group C was higher than of Group B and the average of Group B higher than that of Group A without any statistical significance (p > 0.05). The averages of serum type IV collagen of eighteen patients with histologic abnormalities (Group B and C) and twenty four patients without fibrosis (Group A and B) were 3.73 +/- 1.06 ng/mL and 3.55 +/- .88 ng/mL respectively. Upon comparison of these averages with the those of Group A and C, no statistical significance was established (p > 0.05). CONCLUSION : In chronic hepatitis B carriers with normal LFT findings, levels of serum type IV collagen were elevated along with histologic severities without statistical significance, therefore can not represent the changing degree of the histologic findings. Liver biopsy is considered to be one of the most accurate tool to assess the histologic status of the liver.

Characterization of Changes in Cells and Extracellular Matrix Components during the Regenerative Processes in the Resected Rat Thyroid / 대한해부학회지

Thyroid gland is composed of follicles surrounded by basement membrane, which is known to be related to the regenerative processes in several organs. This study was performed to observe the morphological details and changes of the basement membrane components, which are the presumtive factors in thyroid regeneration, with time sequences after partial thyroidectomy and then the relations between the components and thyroid regeneration were confirmed. Thyroid galnds of adult male rats were examined before and 1, 2, 3, 4, 5, 7 and 10 days after bilateral partial[50-60%] thyroidectomy. The basememnt membranes of follicles were prominent with high eosinophilicity at later stage when H & E stained. But in PAS and EM staining, the basement membrane of the operated groups didn`t show any specific changes comparing with control group but the dense collagenous fibers at the interfollicular space outside the membrane. Immunostaining of proliferating cell nuclear antigen[PCNA], which reflects the growth fraction, showed 2.3% positivity of total follicular cells in control group. The PCNA positive ratio in experimental groups were 10.3%, 15.9%, 19.9%, 12.2%, 10.5%, 1.9%, 2.7% on postoperative 1, 2, 3, 4, 5, 7, 10 days respectively. In unilaterally thyroidectomized rats, the resected lobe revealed 18.2% of PCNA positive ratio 3 days after operation, while that in the unresected lobe was only 5.9%. This suggested the predominence of local factors in thyroid regeneration. Meanwhile, with the double immunostaining of calcitonin and PCNA discriminate between follicular cells and C-cells among the PCNA positive cells, PCNA positive C-cells were very rare. The immunostaining of laminin, fibronectin, and collagen IV showed varying intensity with the progress of regeneration. Stainability for collagen IV was maintained in all groups with some increase in 5- and 7-day groups. Laminin was well localized to the basement membrane of the control follicle, and the staining intensity for laminin was markedly increased with additional cytoplasmic staining in follicular cells in 1- to 3-day groups and then decreased to attain the control level in 10-day group. In case of fibronectin, the control follicle showed scarce staining, but the resected group showed strong positivity for fibronectin with the most intense staining in 1- to 3-day groups. Immunostaining for fibronectin still showes in 10-day group with the gradual disappearance of immunoreactivity in the center of the lobe. This study revealed the accompaning changes of the basement membrane components during the regeneration process of partially resected thyroid glands. Among them, collagen IV seems to support the structural integrity of the basement membrane. Laminin and fibronectin were supposed to be related to the thyroid follicular regeneration.