Development of a novel cell-based assay to diagnose recurrent focal segmental glomerulosclerosis patients

Kidney Int. 2019 Mar;95(3):708-716. doi: 10.1016/j.kint.2018.10.030. Epub 2019 Jan 29.


Definitive diagnosis of glomerular disease requires a kidney biopsy, an invasive procedure that may not be safe or feasible to perform in all patients. We developed a noninvasive, accurate, and economical diagnostic assay with easy commercial adaptability to detect recurrent focal segmental glomerulosclerosis (rFSGS) after kidney transplant. Since FSGS involves podocyte damage and death, our approach involved mRNA profiling of cultured podocytes treated with plasma from patients with rFSGS to identify upregulated genes involved in podocyte damage. For concept validation, three upregulated pro-apoptotic candidate genes (IL1β, BMF, and IGFBP3) were selected, and their promoter regions were cloned into a luciferase-based reporter vector and transfected into podocytes to generate stable podocyte cell lines. Strikingly, when exposed to rFSGS patient plasma, these cell lines showed increased reporter activity; in contrast, no reporter activity was noted with plasma from patients with non-recurrent FSGS or membranous nephropathy. Area under the receiver operating characteristics curves (AUCs) for models discriminating between rFSGS and other nephropathies (non-recurrent FSGS and membranous nephropathy) and between rFSGS and non-recurrent FSGS ranged from 0.81 to 0.86, respectively. Estimated sensitivities and specificities for the diagnosis of rFSGS were greater than 80% for the IL1β and BMF cell lines, and were slightly lower for the IGFBP3 cell line. Importantly, the novel approach outlined here for the diagnosis of rFSGS is widely applicable to the design of sensitive and specific diagnostic/prognostic assays for other glomerular diseases.

Keywords: RNA-Seq; diagnosis; kidney; luciferase; podocytes; promoter; rFSGS.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism
  • Biological Assay / methods*
  • Cell Line
  • Diagnosis, Differential
  • Gene Expression Profiling
  • Genes, Reporter
  • Glomerulosclerosis, Focal Segmental / blood
  • Glomerulosclerosis, Focal Segmental / complications
  • Glomerulosclerosis, Focal Segmental / diagnosis*
  • Humans
  • Insulin-Like Growth Factor Binding Protein 3 / genetics
  • Insulin-Like Growth Factor Binding Protein 3 / metabolism
  • Interleukin-1beta / genetics
  • Interleukin-1beta / metabolism
  • Kidney Failure, Chronic / etiology
  • Kidney Failure, Chronic / surgery
  • Kidney Transplantation
  • Luciferases / genetics
  • Plasma / metabolism
  • Podocytes / metabolism*
  • Promoter Regions, Genetic / genetics
  • RNA, Messenger / metabolism
  • RNA-Seq
  • ROC Curve
  • Recurrence


  • Adaptor Proteins, Signal Transducing
  • BMF protein, human
  • IGFBP3 protein, human
  • IL1B protein, human
  • Insulin-Like Growth Factor Binding Protein 3
  • Interleukin-1beta
  • RNA, Messenger
  • Luciferases