ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Abstract: TH-PO0698

Loss of Decay-Accelerating Factor in Neutrophils Attenuates Proteinuria in a Murine Model of FSGS

Session Information

Category: Glomerular Diseases

  • 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology

Authors

  • Bigatti, Carolina, Icahn School of Medicine at Mount Sinai, New York, New York, United States
  • Cocchini, Lorenzo, IRCCS Ospedale San Raffaele, Milan, Lombardy, Italy
  • Korogodsky, Dana, Icahn School of Medicine at Mount Sinai, New York, New York, United States
  • Angeletti, Andrea, Istituto Giannina Gaslini, Genoa, Liguria, Italy
  • Cravedi, Paolo, Icahn School of Medicine at Mount Sinai, New York, New York, United States
Background

Focal segmental glomerulosclerosis (FSGS) is a major cause of nephrotic syndrome, but its pathophysiology is still unclear. Complement activation has been implicated in disease progression, but the involvement of immune cells, especially neutrophils, has not been clearly defined. Decay-accelerating factor (DAF, also known as CD55) is a complement regulatory protein expressed on neutrophils that may influence their survival and effector function. To test the role of DAF and complement activation in neutrophils in FSGS pathophysiology, we developed mice with conditional deletion or overexpression of DAF in neutrophils

Methods

Male DAFΔS100A8, DAFTgS100A8, and DAFfl/fl mice (aged 8-12 week) received a single retroorbital injection of adriamycin (21 mg/kg). Urinary albumin-to-creatinine ratio (A/C) was measured for 5 weeks. Statistical analysis was performed using a two-way ANOVA.

Results

DAFΔS100A8 developed significantly lower proteinuria compared to DAFfl/fl mice at day 21 and 35 (p=0.038 and p=0.0011, respectively). To further confirm the possible role of neutrophils DAF in glomerular injury, we analyzed transgenic mice overexpressing DAF in neutrophils (DAFTgS100A8), which showed a marked increase in A/C at day 7, 21, 35 (figure 1). Flow cytometry revealed no difference in the percentage of renal CD45+CD11b+Ly6G+ neutrophils among groups across multiple timepoints (day 0, 1, 3, 5, 14, 35).

Conclusion

These findings suggest that DAF expression on neutrophils promotes glomerular injury in adriamycin-induced FSGS. Loss of neutrophil DAF protects against proteinuria, possibly by limiting effector functions such as Neutrophils Extracellular Traps (NET) release or Radical Oxygen species (ROS) production. Neutrophil-specific modulation of complement regulatory pathways may represent a novel therapeutic target in FSGS.

Digital Object Identifier (DOI)