Role of Immune Cell-Podocyte Crosstalk in the Pathogenesis of APOL1-FSGS and Proteinuric Kidney Disease

Abstract

Nearly 600,000 Americans suffer from end-stage kidney disease (ESKD), a failure of kidney function that necessitates either dialysis or a kidney transplant. Medicare expenditures for ESKD exceed $28 billion annually. The vast majority of ESKD in the United States is due to glomerular disease – a process in which the filtering component of the kidney is damaged, resulting in a severe loss of protein in the urine known as nephrotic syndrome, a Fiscal Year 2022 (FY22) Peer Reviewed Medical Research Program (PRMRP) Topic Area. While Americans of African ancestry make up 13% of the United States and Veteran population, they account for 35% of kidney failure. This large health disparity is partly attributed to the carriage of risk alleles in APOL1 (referred to G1/G2 risk alleles), which was discovered a little over a decade ago. Unfortunately, those with APOL1 risk variants manifest with Focal Segmental Glomerulosclerosis (FSGS) (FY22 PRMPP Topic Area), which is the most common form of nephrotic syndrome. However, limited mechanistic understanding of this disease process has hindered novel treatments, especially due to the lack of suitable animal models for study. In our current research, we have made a mouse model that expresses human APOL1 risk alleles. Upon stimulation with an inflammatory agent, interferon, these mice develop excessive protein loss in the urine and kidney features that resemble human FSGS. Using data in humans, we have also identified for the first time that cells of the immune system, in addition to kidney cells, may play a profound role in this disease process. We hypothesize that specific immune cells in individuals with G1/G2 APOL1 release much more interferon which damages the kidney filtration barrier, resulting in accumulation of misfolded proteins. Our first aim will study immune cell to podocyte (cells that line the kidney filtration barrier) crosstalk. The second aim will determine how excess interferons damage the podocyte using our novel mouse models expressing all APOL1 variants. Successful completion of this grant may lead to identification of novel mechanisms and thus druggable targets, leading to potential weapons in the fight against the progression of FSGS to ESKD.

Document Details

Document Type
DoD Grant Award
Publication Date
Jan 04, 2024
Source ID
HT94252310441

Entities

People

  • Madhav Menon

Organizations

  • United States Army
  • Yale University

Tags

Fields of Study

  • Biology
  • Medicine

Readers

  • Molecular and Cellular Biology
  • Oncology

Technology Areas

  • Biotechnology