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Liu J, Qu Z, Chen H, Sun W, Jiang Y. Increased levels of circulating class-switched memory B cells and plasmablasts are associated with serum immunoglobulin G in primary focal segmental glomerulosclerosis patients. Int Immunopharmacol 2021; 98:107839. [PMID: 34111735 DOI: 10.1016/j.intimp.2021.107839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 05/24/2021] [Accepted: 05/29/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Focal segmental glomerulosclerosis (FSGS) is a kidney-specific autoimmune disease, but its pathogenesis is not fully known. The present study detected the frequencies of circulating memory B cells and plasmablasts and other clinical parameters in FSGS. METHODS We monitored 16 primary FSGS patients and 23 healthy controls (HC). Flow cytometry was used to analyze circulating memory B cell and plasmablastspercentages. Serum IgG levels were detected using a cytometric bead array (CBA). RESULTS The proportions of CD27 + IgD- class-switched memory B cells (P = 0.0002), CD27 + IgD-IgG + class-switched memory B cells (P < 0.0001), CD27hiCD38hi plasmablasts (P < 0.0001) and CD138 + plasma cells (P < 0.0001) were markedlyelevated in FSGS patients, and the frequency of CD38 + IgG + plasmablasts (P < 0.0001) and serum IgG levels (P < 0.0001) were lower compared to HC. In the FSGS patients, the frequency of CD27 + IgD-IgG + class-switched memory B cells negatively correlated with CD38 + IgG + plasmablasts (P = 0.0183, R = -0.3375), serum IgG levels (P = 0.0061, R = -0.4263) and estimated glomerular filtration rate (eGFR) (P = 0.0074, R = -0.4114) but positively correlated with 24-h urinary protein levels (P = 0.0077, R = 0.4085). The proportion of CD38 + IgG + plasmablasts positively correlated with serum IgG levels (P = 0.0151, R = 0.3538). CONCLUSIONS We speculate that alterations in the frequencies of CD27 + IgD-IgG + class-switched memory B cells and plasmablasts may be responsible for the etiopathogenesis of FSGS.
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Affiliation(s)
- Jing Liu
- Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, Genetic Diagnosis Center, The First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Zhihui Qu
- Department of Nephrology, The First Hospital of Jilin University, Changchun 130021, Jilin, China.
| | - Hongyu Chen
- Peking University Health Science Center, Beijing 100191, China.
| | - Weixia Sun
- Department of Nephrology, The First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Yanfang Jiang
- Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, Genetic Diagnosis Center, The First Hospital of Jilin University, Changchun 130021, Jilin, China.
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Safdar RS, Mehar MF, Khan AA, Buzdar N. Focal Segmental Glomerulosclerosis in Paediatric Population of South Punjab Pakistan: A Tertiary Care Hospital Experience. Pak J Med Sci 2021; 37:510-514. [PMID: 33679941 PMCID: PMC7931269 DOI: 10.12669/pjms.37.2.3535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objectives: To find out frequency, clinicopathological features, response of treatment and outcome among children with primary focal segmental glomerulosclerosis (FSGS). Methods: This retrospective, non-interventional medical charts review study was conducted from a period of January 2011 to January 2020 at Pediatric Department of Nishtar Medical University Hospital, Multan, Pakistan. During the nine years study period, children of both genders, aged less than 16 years, with renal biopsies proven FSGS were included. Patient’s demographic along with clinical and laboratory data, urine dipstick for proteinuria, renal functions, 24 hours urinary protein and ultrasonography findings of kidneys, ureters and bladder (KUB) were noted from case records. Response rates of various treatment options and their outcome like remission, partial remission, no remission with stable kidney disease & no remission with progression of kidney disease were noted. Results: During the study duration, out of 307 renal biopsies performed in glomerulonephritis cases, 124 (40.4%) had primary FSGS. In 124 primary FSGS cases, mean age was 8.83±3.05 years while most of the children, 70 (56.5%) were above 10 years of age. Majority of the cases, 64 (51.6%) were male. Mean follow up duration was noted to be 28.35+18.47 months. Most of the cases, 68 (54.8%) were found to have complete remission, 22 (17.7%) partial remission while 11 (8.9%) progressed to ESKD. Conclusions: Among children, frequency of primary FSGS was high at our setting. Most of the cases achieved sustained remission rates with the help of immunosuppressive drugs. Cyclosporine and tacrolimus were found to be the most effective drugs.
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Affiliation(s)
- Rabia Saleem Safdar
- Rabia Saleem Safdar, FCPS (Pediatric Medicine), Department of Pediatrics, Ward Number 19, Nishtar Medical University Hospital, Multan, Pakistan
| | - M Faisal Mehar
- M. Faisal Mehar, FCPS (Pediatric Medicine), Department of Pediatrics, Ward Number 19, Nishtar Medical University Hospital, Multan, Pakistan
| | - Afsheen Asghar Khan
- Afsheen Asghar, FCPS (Pediatric Medicine), Department of Pediatrics, Ward Number 19, Nishtar Medical University Hospital, Multan, Pakistan
| | - Nusrat Buzdar
- Nusrat Buzdar, FCPS (Pediatric Medicine), Department of Pediatrics, Ward Number 19, Nishtar Medical University Hospital, Multan, Pakistan
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Kalantari S, Nafar M, Rutishauser D, Samavat S, Rezaei-Tavirani M, Yang H, Zubarev RA. Predictive urinary biomarkers for steroid-resistant and steroid-sensitive focal segmental glomerulosclerosis using high resolution mass spectrometry and multivariate statistical analysis. BMC Nephrol 2014; 15:141. [PMID: 25182141 PMCID: PMC4236676 DOI: 10.1186/1471-2369-15-141] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 08/26/2014] [Indexed: 01/10/2023] Open
Abstract
Background Focal segmental glomerulosclerosis (FSGS) is a glomerular scarring disease diagnosed mostly by kidney biopsy. Since there is currently no diagnostic test that can accurately predict steroid responsiveness in FSGS, prediction of the responsiveness of patients to steroid therapy with noninvasive means has become a critical issue. In the present study urinary proteomics was used as a noninvasive tool to discover potential predictive biomarkers. Methods Urinary proteome of 10 patients (n = 6 steroid-sensitive, n = 4 steroid-resistant) with biopsy proven FSGS was analyzed using nano-LC-MS/MS and supervised multivariate statistical analysis was performed. Results Twenty one proteins were identified as discriminating species among which apolipoprotein A-1 and Matrix-remodeling protein 8 had the most drastic fold changes being over- and underrepresented, respectively, in steroid sensitive compared to steroid resistant urine samples. Gene ontology enrichment analysis revealed acute inflammatory response as the dominant biological process. Conclusion The obtained results suggest a panel of predictive biomarkers for FSGS. Proteins involved in the inflammatory response are shown to be implicated in the responsiveness. As a tool for biomarker discovery, urinary proteomics is especially fruitful in the area of prediction of responsiveness to drugs. Further validation of these biomarkers is however needed.
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Affiliation(s)
| | | | | | | | | | | | - Roman A Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden.
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The novel diagnostic biomarkers for focal segmental glomerulosclerosis. Int J Nephrol 2014; 2014:574261. [PMID: 24790760 PMCID: PMC3984796 DOI: 10.1155/2014/574261] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 02/21/2014] [Accepted: 02/24/2014] [Indexed: 11/17/2022] Open
Abstract
Background. Focal segmental glomerulosclerosis (FSGS) is a glomerular injury with various pathogenic mechanisms. Urine proteome panel might help in noninvasive diagnosis and better understanding of pathogenesis of FSGS. Method. We have analyzed the urine sample of 11 biopsy-proven FSGS subjects, 8 healthy controls, and 6 patients with biopsy-proven IgA nephropathy (disease controls) by means of liquid chromatography tandem mass spectrometry (nLC-MS/MS). Multivariate analysis of quantified proteins was performed by principal component analysis (PCA) and partial least squares (PLS). Results. Of the total number of 389 proteins, after multivariate analysis and additional filter criterion and comparing FSGS versus IgA nephropathy and healthy subjects, 77 proteins were considered as putative biomarkers of FSGS. CD59, CD44, IBP7, Robo4, and DPEP1 were the most significant differentially expressed proteins. These proteins are involved in pathogenic pathways: complement pathway, sclerosis, cell proliferation, actin cytoskeleton remodeling, and activity of TRPC6.There was complete absence of DPEP1 in urine proteome of FSGS subjects compared with healthy and disease controls. DPEP1 acts via leukotrienes on TRPC6 and results in increased podocyte motility and proteinuria. Conclusion. The results suggest a panel of candidate biomarkers for noninvasive diagnosis of FSGS, while complete absence of DPEP1 might represent a novel marker of FSGS.
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Kalantari S, Nafar M, Samavat S, Rezaei-Tavirani M, Rutishauser D, Zubarev R. Urinary prognostic biomarkers in patients with focal segmental glomerulosclerosis. Nephrourol Mon 2014; 6:e16806. [PMID: 25032130 PMCID: PMC4090581 DOI: 10.5812/numonthly.16806] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 12/29/2013] [Accepted: 01/02/2014] [Indexed: 01/24/2023] Open
Abstract
Background: Focal segmental glomerulosclerosis (FSGS) is a type of nephrotic syndrome which is diagnosed by renal biopsy. Degree of the proteinuria, renal dysfunction, histologic findings and the response to therapy are some factors used for evaluating the prognosis of FSGS. Objectives: In the present study, we attempted to discover some protein candidates for disease prognosis related to glomerular filtration rate (renal dysfunction). Patients and Methods: Urine samples were collected from ten patients. Urine proteome was extracted and trypsinated. Digested peptides were separated and identified by nano-flow LC-MS/MS. Protein content were determined using label-free quantification method. Protein profiles were analyzed using supervised multivariate statistical method. Results: Output of a predictive model was 54 significant proteins of which ribonuclease 2 and haptoglobin had the greatest fold change in terms of overrepresentation and underrepresentation in patients with the best and worse prognosis, respectively. Complement and coagulation cascades were the only significant pathways which were impaired in FSGS. Conclusions: Urinary biomarkers can potentially be used as non-invasive prognostic markers. However these candidate biomarkers need further validation by an alternative method and in a larger cohort.
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Affiliation(s)
- Shiva Kalantari
- Department of Basic Sciences, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
| | - Mohsen Nafar
- Department of Nephrology, Shahid Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
- Urology and Nephrology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
- Chronic Kidney Disease Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
- Corresponding author: Mohsen Nafar, Department of Nephrology, Shahid Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran. Tel/Fax: +98-2122580333, E-mail:
| | - Shiva Samavat
- Department of Nephrology, Shahid Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
- Urology and Nephrology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
- Chronic Kidney Disease Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran
| | | | - Dorothea Rutishauser
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
- SciLifeLab, Stockholm, Sweden
| | - Roman Zubarev
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
- SciLifeLab, Stockholm, Sweden
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Hebert LA, Parikh S, Prosek J, Nadasdy T, Rovin BH. Differential diagnosis of glomerular disease: a systematic and inclusive approach. Am J Nephrol 2013; 38:253-66. [PMID: 24052039 DOI: 10.1159/000354390] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 07/16/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND Glomerular disease is a complex and evolving topic. In evaluating a specific case it is not unusual for the clinician to ask: 'Am I missing something? Should I biopsy? When? Should I treat first, then biopsy?' This work, which is both evidence and experience based, is intended to address each of these concerns and many other issues relevant to the differential diagnosis of glomerular disease. SUMMARY The central approach is the use of diagnostic algorithms that are based on quantitative measures routinely obtained early in the course of the diagnostic evaluation. The algorithms are designed to be easy to navigate, systematic, and inclusive. Also provided is a detailed and prioritized list of recommended diagnostic testing, and the rationale for each test. KEY MESSAGE This work is intended to facilitate accurate diagnosis in the individual patient presenting with evidence of glomerular disease.
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Affiliation(s)
- Lee A Hebert
- Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA.
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Chou YH, Lien YC, Hu FC, Lin WC, Kao CC, Lai CF, Chiang WC, Lin SL, Tsai TJ, Wu KD, Chen YM. Clinical outcomes and predictors for ESRD and mortality in primary GN. Clin J Am Soc Nephrol 2012; 7:1401-8. [PMID: 22798538 DOI: 10.2215/cjn.04500511] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND OBJECTIVES Relatively little is known about the long-term outcomes of different histologic types of primary glomerulonephritis in Asian populations. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS From 1993 to 2006, 987 patients undergoing renal biopsy were studied, and 580 patients (mean age=44.4 years, male=58.5%) with the four most common forms of glomerulonephritis (membranous nephropathy, focal and segmental glomerulosclerosis, IgA nephropathy, and minimal change disease) were selected for analysis. Median follow-up period was 5.9 (interquartile range=5.7) years. RESULTS The focal and segmental glomerulosclerosis group displayed the highest incidence of ESRD (25.8%) and the fastest decline of estimated GFR (4.6 ml/min per 1.73 m(2) per year). The IgA nephropathy group also had a higher rate of ESRD than the membranous nephropathy patients (19.2% versus 4.3%, P<0.001). In contrast, the membranous nephropathy group exhibited an overall death rate similar to the focal and segmental glomerulosclerosis group (17.2% versus 14.4%) but higher than the IgA nephropathy and minimal change disease patients (4.6% and 3.7%, respectively, P<0.001). The most powerful predictor for ESRD was focal and segmental glomerulosclerosis, whereas the strongest predictor for all-cause mortality was membranous nephropathy with higher proteinuria. Protectors against ESRD included male sex and higher hemoglobin. CONCLUSIONS Most predictors for ESRD and overall mortality found in this ethnic Chinese cohort were similar to other studies. However, some risk factors linked with distinct glomerular pathologies displayed differential clinical outcomes.
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Affiliation(s)
- Yu-Hsiang Chou
- Renal Division, Department of Internal Medicine, National Taiwan University Hospital, Yun-Lin Branch, Yunlin County, Taiwan
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Wang X, Sakatsume M, Sakamaki Y, Inomata S, Yamamoto T, Narita I. Quantitative histological analysis of SM22α (transgelin) in an adriamycin-induced focal segmental glomerulosclerosis model. Nephron Clin Pract 2011; 120:e1-11. [PMID: 22205114 DOI: 10.1159/000329664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 04/29/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS SM22α, transgelin, has been revealed to be specifically expressed in glomerular epithelial cells and interstitial cells, according to the nature of the renal injury. In this study, quantitative analyses of SM22α positivity were performed to investigate the pathological significance of its expression. METHODS Kidney samples of adriamycin nephropathy underwent immunohistochemistry with a newly established anti-SM22α monoclonal antibody. The SM22α positivity was quantified by an image analyzer. The correlation of the histological values with biochemical data was investigated statistically. Microstructural localization of SM22α was studied by immunoelectron microscopy. RESULTS SM22α was expressed along the dense basal microfilaments of degenerating podocytes, and diffusely in interstitial cells. Both the extent and intensity of SM22α expression in glomerular and tubulointerstitial area were correlated with the deterioration of renal function and the severity of proteinuria. Stepwise multiple linear regression analysis revealed that the extent of its positivity in glomerular or tubulointerstitial area was the determinant of the amount of proteinuria or the deterioration of creatinine clearance (Ccr), respectively. Inversely, the deterioration of Ccr was the most important predictor of SM22α expression. CONCLUSION SM22α expression in podocytes and interstitial cells represented the severity of proteinuria and the deterioration of renal function. SM22α expression in renal tissues might be a hallmark of kidney diseases.
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Affiliation(s)
- Xingzhi Wang
- Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
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C1q nephropathy in the pediatric population: pathology and pathogenesis. Pediatr Nephrol 2010; 25:1385-96. [PMID: 20180137 DOI: 10.1007/s00467-009-1429-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 12/11/2009] [Accepted: 12/15/2009] [Indexed: 10/19/2022]
Abstract
C1q nephropathy was originally described nearly 25 years ago by Jennette and Hipp. Since that time there have been a limited number of publications on C1q nephropathy, most of them in the pediatric literature. Despite reported incidences as high as 16% in some pediatric biopsy series, a consensus definition on the diagnosis of C1q nephropathy is lacking and its existence as a distinct clinical disease entity remains controversial. The purpose of this review is to discuss the biology of C1q in the context of mechanisms of C1q deposition, and to provide a detailed analysis of the published pediatric case series with a focus on the pathological criteria used to establish the diagnosis of C1q nephropathy as well as long-term outcomes in children.
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El-Refaey AM, Bakr A, Hammad A, Elmougy A, El-Houseeny F, Abdelrahman A, Sarhan A. Primary focal segmental glomerulosclerosis in Egyptian children: a 10-year single-centre experience. Pediatr Nephrol 2010; 25:1369-73. [PMID: 20195645 DOI: 10.1007/s00467-010-1448-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Revised: 12/19/2009] [Accepted: 12/22/2009] [Indexed: 10/19/2022]
Abstract
Primary focal segmental glomerulosclerosis (FSGS) in children accounts for 7-20% of all cases of idiopathic nephrotic syndrome (NS). To evaluate the clinical course of children with primary FSGS, the records of 72 patients with biopsy-proven FSGS admitted between 1995 and 2008 were retrospectively analysed. Forty-eight patients were male (66.7%). The mean age at presentation was 76.5 +/- 54 (range 12-192) months. The mean duration of follow-up was 76.3 +/- 42 (range 9-156) months. Seventeen patients (23.6%) presented with gross haematuria at initial presentation, 15 (20.8%) presented with hypertension and 10 patients (14%) presented with chronic renal insufficiency (CRI). The initial response to oral prednisolone was steroid resistance in 63 patients (87.5%) and steroid dependence in 4 patients (5%), while 5 patients (6.9%) were biopsied from the start because of atypical presentation. According to pathological classification, there were the tip variant (2%), collapsing variant (6%), perihilar variant (7%) and NOS (not otherwise specified; 85%). At the last clinical visit, 12 patients (16.7%) were in complete remission and 11 (15.3%) had progressed to CRI. Renal survival rates at 5 and 10 years were 93% and 68%, respectively. In conclusion, in this study we had a low percentage of FSGS, and fewer patients presenting with gross haematuria and hypertension compared with previous reports. In addition, the short-term overall renal survival seems to be better in our cohort.
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Affiliation(s)
- Ahmed M El-Refaey
- Pediatric Nephrology Unit, Mansoura University Children's Hospital, Mansoura University, Algomhoria Street, Mansoura, Egypt.
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Guay-Woodford LM, Knoers NV. Genetic Testing: Considerations for Pediatric Nephrologists. Semin Nephrol 2009; 29:338-48. [DOI: 10.1016/j.semnephrol.2009.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Otaki Y, Miyauchi N, Higa M, Takada A, Kuroda T, Gejyo F, Shimizu F, Kawachi H. Dissociation of NEPH1 from nephrin is involved in development of a rat model of focal segmental glomerulosclerosis. Am J Physiol Renal Physiol 2008; 295:F1376-87. [PMID: 18715943 DOI: 10.1152/ajprenal.00075.2008] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is a disease showing severe proteinuria, and the disease progresses to end-stage kidney failure in many cases. However, the pathogenic mechanism of FSGS is not well understood. The slit diaphragm (SD), which bridges the neighboring foot processes of glomerular epithelial cells, is understood to function as a barrier of the glomerular capillary wall. To investigate the role of SD dysfunction in the development of FSGS, we analyzed the expression of SD-associated molecules in rat adriamycin-induced nephropathy, a mimic of FSGS. The staining of the SD molecules nephrin, podocin, and NEPH1 had already shifted to a discontinuous dotlike pattern at the initiation phase of the disease, when neither proteinuria nor any morphological alterations were detected yet. The alteration of NEPH1 expression was the most evident among the molecules examined, and NEPH1 was dissociated from nephrin at the initiation phase. On day 28, when severe proteinuria was detected and sclerotic changes were already observed, alteration of the expressions of nephrin, podocin, and NEPH1 worsened, but no alteration in the expression of other SD-associated molecules or other podocyte molecules was detected. It is postulated that the dissociation of NEPH1 from nephrin initiates proteinuria and that the SD alteration restricted in these molecules plays a critical role in the development of sclerotic changes in FSGS.
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Affiliation(s)
- Yasuhiro Otaki
- Department of Cell Biology, Institute of Nephrology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Niigata, 951-8510, Japan
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McKenzie LM, Hendrickson SL, Briggs WA, Dart RA, Korbet SM, Mokrzycki MH, Kimmel PL, Ahuja TS, Berns JS, Simon EE, Smith MC, Trachtman H, Michel DM, Schelling JR, Cho M, Zhou YC, Binns-Roemer E, Kirk GD, Kopp JB, Winkler CA. NPHS2 variation in sporadic focal segmental glomerulosclerosis. J Am Soc Nephrol 2007; 18:2987-95. [PMID: 17942957 DOI: 10.1681/asn.2007030319] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Mutations in NPHS2, the gene that encodes podocin, are well-established causes of both familial and sporadic steroid-resistant focal segmental glomerulosclerosis (FSGS) in the pediatric population, but have not been well-characterized in late-onset disease. To investigate the role of NPHS2 polymorphisms in sporadic cases of late-onset FSGS, we studied 377 biopsy-confirmed FSGS cases and 919 controls. We identified 18 single nucleotide polymorphisms (SNPs) by resequencing a subgroup of cases and controls, and subsequently genotyped African-American and European-American cases and controls for five missense SNPs, three SNPs within introns, and four SNPs in the 3' untranslated region. No homozygotes or compound heterozygotes were observed for any missense mutation. R138Q carriers were more frequent among FSGS cases relative to controls (OR = 4.9, P = 0.06), but heterozygosity for the other four missense mutations was equally distributed among FSGS cases and controls. Finally, a common haplotype of noncoding SNPs carried by 20% of African-Americans, but not observed in European-Americans, was strongly associated with a 50% reduction in risk for sporadic FSGS (OR = 0.5, P = 0.001). These results indicate that genetic variation or mutation of NPHS2 may play a role in late-onset sporadic FSGS.
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Affiliation(s)
- Louise M McKenzie
- Laboratory of Genomic Diversity, SAIC-Frederick, National Cancer Institute, NCI-Frederick, Frederick, Maryland, USA
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Bennett MR, Czech KA, Arend LJ, Witte DP, Devarajan P, Potter SS. Laser capture microdissection-microarray analysis of focal segmental glomerulosclerosis glomeruli. Nephron Clin Pract 2007; 107:e30-40. [PMID: 17684420 DOI: 10.1159/000106775] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 04/24/2007] [Indexed: 11/19/2022] Open
Abstract
Focal segmental glomerulosclerosis (FSGS) is a major cause of end-stage renal disease. In this report we used laser capture microdissection to purify diseased glomeruli, and microarrays to provide universal gene expression profiles. The results provide a deeper understanding of the molecular mechanisms of the disease process and suggest novel therapeutic strategies. Consistent with earlier studies, molecular markers of the differentiated podocyte, including WT1, nephrin, and VEGF, were dramatically downregulated in the diseased glomerulus. We also observed multiple changes consistent with increased TGF-beta signaling, including elevated expression of TGF-beta(2), TGF-beta(3), SMAD2, TGF-beta(1) receptor, and thrombospondin. In addition, there was relatively low level expression of Csf1r, a marker of macrophages, but elevated expression of the chemokines CXCL1, CXCL2, CCL3, and CXCL14. We also observed strongly upregulated expression of Sox9, a transcription factor that can drive a genetic program of chondrogenesis and fibrosis. Further, the gene with the greatest fold increase in expression in the diseased glomerulus was osteopontin, which has been previously strongly implicated in kidney fibrosis in the unilateral ureteral obstruction mouse model. These results confirm old findings, and indicate the involvement of new genetic pathways in the cause and progression of FSGS.
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Affiliation(s)
- Michael R Bennett
- Division of Nephrology and Hypertension, Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
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Barisoni L, Schnaper HW, Kopp JB. A proposed taxonomy for the podocytopathies: a reassessment of the primary nephrotic diseases. Clin J Am Soc Nephrol 2007; 2:529-42. [PMID: 17699461 DOI: 10.2215/cjn.04121206] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A spectrum of proteinuric glomerular diseases results from podocyte abnormalities. The understanding of these podocytopathies has greatly expanded in recent years, particularly with the discovery of more than a dozen genetic mutations that are associated with loss of podocyte functional integrity. It is apparent that classification of the podocytopathies on the basis of morphology alone is inadequate to capture fully the complexity of these disorders. Herein is proposed a taxonomy for the podocytopathies that classifies along two dimensions: Histopathology, including podocyte phenotype and glomerular morphology (minimal-change nephropathy, focal segmental glomerulosclerosis, diffuse mesangial sclerosis, and collapsing glomerulopathy), and etiology (idiopathic, genetic, and reactive forms). A more complete understanding of the similarities and differences among podocyte diseases will help the renal pathologist and the nephrologist communicate more effectively about the diagnosis; this in turn will help the nephrologist provide more accurate prognostic information and select the optimal therapy for these often problematic diseases. It is proposed that final diagnosis of the podocytopathies should result from close collaboration between renal pathologists and nephrologists and should whenever possible include three elements: Morphologic entity, etiologic form, and specific pathogenic mechanism or association.
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Affiliation(s)
- Laura Barisoni
- Department of Pathology, New York University School of Medicine, New York, New York, USA
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Reidy K, Kaskel FJ. Pathophysiology of focal segmental glomerulosclerosis. Pediatr Nephrol 2007; 22:350-4. [PMID: 17216262 PMCID: PMC1794138 DOI: 10.1007/s00467-006-0357-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 08/01/2006] [Accepted: 08/24/2006] [Indexed: 10/31/2022]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a major cause of idiopathic steroid-resistant nephrotic syndrome (SRNS) and end-stage kidney disease (ESKD). In recent years, animal models and studies of familial forms of nephrotic syndrome helped elucidate some mechanisms of podocyte injury and disease progression in FSGS. This article reviews some of the experimental and clinical data on the pathophysiology of FSGS.
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Affiliation(s)
- Kimberly Reidy
- Division of Pediatric Nephrology, Children’s Hospital at Montefiore, Bronx, NY 10467 USA
| | - Frederick J. Kaskel
- Division of Pediatric Nephrology, Children’s Hospital at Montefiore, 111 East 210th St., Bronx, NY 10467 USA
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Abrantes MM, Cardoso LSB, Lima EM, Silva JMP, Diniz JS, Bambirra EA, Oliveira EA. Clinical course of 110 children and adolescents with primary focal segmental glomerulosclerosis. Pediatr Nephrol 2006; 21:482-9. [PMID: 16520952 DOI: 10.1007/s00467-006-0019-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 10/12/2005] [Accepted: 10/19/2005] [Indexed: 10/24/2022]
Abstract
The purpose of this retrospective cohort study was to report the clinical course of children and adolescents with primary focal segmental glomerulosclerosis (FSGS). The records of 110 patients with biopsy-proven FSGS admitted between 1972 and 2004 were retrospectively reviewed. Demographic, clinical and laboratory data were recorded and histopathological data were reanalyzed by one pathologist who had no information about the outcome of the patients. Renal survival analysis was performed using the Kaplan-Meier method. Differences between subgroups (response to corticosteroids) were assessed by the two-sided log rank test. The median age at admission was 5 years (range: 1-15 years). Forty-two patients (38.2%) presented with hematuria at admission, and 55 (50%) presented blood pressure levels above the 95th percentile. Mean follow-up time was 10 years (SD 5.5). Twenty-four patients (21.8%) presented chronic kidney disease (CKD). It was estimated that the probability of CKD was 8% at 5 years, 17% at 10 years, and 32% at 15 years after diagnosis of nephrotic syndrome. In conclusion, on the basis of the clinical and histological characteristics observed, apparently our cohort of idiopathic FSGS is comparable with other published series. However, the long-term overall renal survival seems to be better in our cohort.
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Affiliation(s)
- Marcelo M Abrantes
- Pediatric Nephrology Unit, Hospital das Clínicas, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
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Dingli D, Larson DR, Plevak MF, Grande JP, Kyle RA. Focal and segmental glomerulosclerosis and plasma cell proliferative disorders. Am J Kidney Dis 2005; 46:278-82. [PMID: 16112046 DOI: 10.1053/j.ajkd.2005.05.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 05/02/2005] [Indexed: 11/11/2022]
Abstract
BACKGROUND Focal and segmental glomerulosclerosis (FSGS) is a common histological finding in patients with proteinuria. The natural history of the condition varies, and although it may be responsive to therapy, FSGS is an important cause of end-stage renal disease. FSGS can be caused by a variety of conditions, but it has been reported rarely in association with a plasma cell disorder. METHODS Mayo Clinic databases were queried and cross-referenced for FSGS and plasma cell disorders. The diagnoses were confirmed, and relevant clinical and laboratory data were abstracted. RESULTS A cohort of 13 patients with "idiopathic" FSGS and a monoclonal plasma cell disorder were identified. Four patients had myeloma, and 9 patients had monoclonal gammopathy of undetermined significance. Patients treated for myeloma experienced improvement in their renal lesion, and the latter relapsed when the myeloma relapsed. CONCLUSION We show that FSGS and plasma cell disorders are temporally and epidemiologically linked. Therapy for the underlying plasma cell disorder can lead to resolution of FSGS. The emerging molecular pathogenesis of both FSGS and myeloma also provides potential mechanisms that link the 2 conditions together. Thus, physicians must rule out a plasma cell proliferative disorder in patients with FSGS before concluding that the renal lesion is idiopathic. Moreover, FSGS may respond favorably after the underlying plasma cell disorder is controlled.
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Affiliation(s)
- David Dingli
- Division of Hematology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
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Rangan GK, Pippin JW, Couser WG. C5b-9 regulates peritubular myofibroblast accumulation in experimental focal segmental glomerulosclerosis. Kidney Int 2005; 66:1838-48. [PMID: 15496154 DOI: 10.1111/j.1523-1755.2004.00957.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND In human focal segmental glomerulosclerosis (FSGS), the tubulointerstitial deposition of the complement (C5b-9) membrane attack complex is correlated with interstitial myofibroblast accumulation and proteinuria. Here, we hypothesized that C5b-9 formation regulates renal myofibroblast accumulation in Adriamycin nephropathy. METHODS Adriamycin nephropathy was induced in complement C6-sufficient (C6+) and C6-deficient (C6-) piebold viral glaxo (PVG) rats. Groups of animals (N= 7 to 8 each) were examined on days 21 and 42. A group of C6+ animals, injected with vehicle, served as the control group. RESULTS C6+ and C6- rats with Adriamycin nephropathy had equivalent proteinuria. C5b-9 deposition was increased and present on the apical surface of proximal tubular epithelial cells (day 21 and 42) and peritubular region (day 42 only) in C6+ rats with Adriamycin nephropathy, and absent in C6- rats. Peritubular myofibroblast accumulation increased in a time-dependent manner in C6+ proteinuric rats (control 1.2 +/- 0.4; Adriamycin nephropathy day 21 11.0 +/- 0.7; Adriamycin nephropathy day 42 19.8 +/- 1.7 cells per high power field). In C6- rats this increase was blunted by 87% and 56% on days 21 and 42, respectively (P < 0.01), and was associated with reduced interstitial extracellular matrix (ECM) deposition. Tubulointerstitial injury, tubular vimentin and interstitial monocyte accumulation were also reduced in C6- rats with Adriamycin nephropathy on day 21, but not at day 42. In contrast, the increase in periglomerular myofibroblast accumulation and glomerulosclerosis in Adriamycin nephropathy were not altered by C6 deficiency. CONCLUSION These data suggest that glomerular ultrafiltration of complement components and the intratubular formation of C5b-9 is a specific promotor of peritubular myofibroblast accumulation in FSGS.
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Affiliation(s)
- Gopala K Rangan
- Division of Nephrology, University of Washington Medical Center, Seattle, Washington, USA.
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Schwab K, Witte DP, Aronow BJ, Devarajan P, Potter SS, Patterson LT. Microarray analysis of focal segmental glomerulosclerosis. Am J Nephrol 2004; 24:438-47. [PMID: 15308877 DOI: 10.1159/000080188] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Accepted: 07/07/2004] [Indexed: 11/19/2022]
Abstract
BACKGROUND Focal segmental glomerulosclerosis (FSGS) is a leading cause of chronic renal failure in children. Recent studies have begun to define the molecular pathogenesis of this heterogeneous condition. Here we use oligonucleotide microarrays to obtain a global gene expression profile of kidney biopsy specimens from patients with FSGS in order to better understand the pathogenesis of this disease. METHODS We extracted RNA from renal biopsy samples of 10 patients with the diagnosis of FSGS and from 5 control kidney samples, and produced labeled cRNA for hybridization to Affymetrix human U133A microarrays. RESULTS We identified a gene expression fingerprint for FSGS that contained 429 of 22,283 possible genes, each with a p < 0.01, using RMA normalization, Welch t test, and at least a 1.8-fold change in 5 of the 10 patients examined. We also found gene expression differences in samples from subsets of patients who had either nephrotic syndrome or renal insufficiency. This screen identified many genes and genetic pathways that have already been implicated in the pathogenesis of FSGS. In addition, we found changes in gene expression in genetic pathways that have not been studied in FSGS. CONCLUSIONS Oligonucleotide DNA microarray analysis of renal biopsy specimens identified a gene expression fingerprint in samples from a heterogeneous population of patients with FSGS. The genes and genetic pathways identified in this study can be compared to results of similar studies of other diseases to examine specificity and used to study the pathogenesis of FSGS.
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Affiliation(s)
- Kristopher Schwab
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA
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