While considerable progress has been achieved in understanding basic mechanisms of glomerular and renal fibrosis, the absence of a true experimental model for human FSGS has made it difficult to clearly understand how these basic mechanisms apply to human idiopathic FSGS. A second major limitation has been that mesenchymal cells such as mesangial cells and interstitial cells and tubular epithelial cells have received the most attention in defining pathways of sclerosis and fibrosis, while a less well studied cell, the podocyte, plays a major role in the injuries leading to FSGS. Recently, the NIDDK initiated a prospective, controlled, randomized trial to study the treatment of FSGS in children and young adults. Our studies aim to perform state-of-the art analysis of the renal biopsy tissue obtained for patient entry into this multicenter study, along with additional cases from our archival files, with a total of >2000 cases, with >200 in children. We will analyze histologic patterns of injury and correlate them with expression by specific glomerular cell types of protein and mRNA of mediators of cell differentiation, proliferation, ECM modulation and inflammatory modulators. These approaches will take advantage of the highly localized injuries in FSGS, i.e. the focal and segmental nature of the sclerosing lesions. Colocalization of mediators with expressions of candidate modulators of the disease process, as proposed in this project, is the first essential step in fulfilling Koch's postulates for establishing a causal role in disease, which can then be explored in complementary studies, e.g. cell culture, proteomic, genomic analyses in future studies. A key element will be the correlation of renal biopsy tissue findings with clinical outcome, to determine markers of prognosis and therapeutic response. These translational studies will utilize findings from the clinical specimens to provide an initial test of the putative pathogenetic roles of the leading molecular """"""""suspects"""""""" that result in FSGS. These approaches could ultimately identify novel therapeutic targets in FSGS.

Public Health Relevance

Scarring of kidneys is a major health problem, and may occur due to a disease called focal segmental glomerulosclerosis (FSGS). This disease may have different patterns. We want to examine if the differences in patterns are important, and whether they develop due to different mechanisms, and whether they have different outcomes and responses to treatment.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK080095-02
Application #
7934590
Study Section
Special Emphasis Panel (ZDK1-GRB-G (O2))
Program Officer
Moxey-Mims, Marva M
Project Start
2009-09-30
Project End
2013-04-30
Budget Start
2010-09-30
Budget End
2013-04-30
Support Year
2
Fiscal Year
2010
Total Cost
$350,135
Indirect Cost
Name
Vanderbilt University Medical Center
Department
Pathology
Type
Schools of Medicine
DUNS #
004413456
City
Nashville
State
TN
Country
United States
Zip Code
37212
D'Agati, Vivette D; Alster, Joan M; Jennette, J Charles et al. (2013) Association of histologic variants in FSGS clinical trial with presenting features and outcomes. Clin J Am Soc Nephrol 8:399-406
Fatima, Huma; Moeller, Marcus J; Smeets, Bart et al. (2012) Parietal epithelial cell activation marker in early recurrence of FSGS in the transplant. Clin J Am Soc Nephrol 7:1852-8
Jefferson, J Ashley; Alpers, Charles E; Shankland, Stuart J (2011) Podocyte biology for the bedside. Am J Kidney Dis 58:835-45