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Updated: Oct 9, 2026

Analyses of Proteinuria, Renal Infiltration of Leukocytes, and Renal Deposition of Proteins in Lupus-prone MRL/lpr Mice
09:43

Analyses of Proteinuria, Renal Infiltration of Leukocytes, and Renal Deposition of Proteins in Lupus-prone MRL/lpr Mice

Published on: June 8, 2022

Plasminogen activator inhibitor-1 gene polymorphism 4G/4G genotype and lupus nephritis in Chinese patients

A Y Wang1, P Poon, F M Lai

  • 1Department of Medicine and Therapeutics, The Chinese University of Hong Kong, The Prince of Wales Hospital, Hong Kong, China.

Kidney International
|March 22, 2001
PubMed

Insights

The 4G/5G polymorphism in the plasminogen activator inhibitor-1 (PAI-1) gene is linked to lupus nephritis activity, not its development or chronicity. The 4G4G genotype is associated with increased disease severity and necrotizing lesions in lupus nephritis patients.

Area of Science:

  • Nephrology
  • Genetics
  • Immunology

Background:

  • Coagulation and fibrinolytic system dysregulation is implicated in lupus nephritis glomerular damage.
  • Glomerular thrombosis in lupus nephritis correlates with future glomerular sclerosis.
  • Plasminogen activator inhibitor-1 (PAI-1) gene is overexpressed in lupus nephritis kidneys, correlating with disease progression.

Purpose of the Study:

  • To investigate the association between the PAI-1 gene 4G/5G polymorphism and the development/severity of lupus nephritis.
  • To determine if PAI-1 gene variants influence lupus nephritis activity and lesion extent.

Main Methods:

  • Genotyping for the PAI-1 4G/5G polymorphism was performed on 118 systemic lupus erythematosus (SLE) patients and 103 healthy controls using standard polymerase chain reaction.
  • PAI-1 genotype distributions were analyzed in relation to lupus nephritis development and severity.

Main Results:

  • No significant difference in PAI-1 4G/5G allele frequencies or genotype distribution was observed between SLE patients and controls, or between SLE patients with and without nephritis.
  • Lupus nephritis patients with the 4G4G genotype exhibited significantly heavier proteinuria, higher disease activity index, and more extensive necrotizing lesions compared to those with 4G5G or 5G5G genotypes.
  • These associations persisted even when analyzing only class III and IV lupus nephritis, but no link was found with nephritis chronicity.

Conclusions:

  • The 4G/5G polymorphism of the PAI-1 gene is associated with the activity and severity of lupus nephritis, particularly necrotizing lesions.
  • The 4G4G genotype does not increase the risk of developing SLE or lupus nephritis but predicts more active disease and severe lesions.
  • PAI-1 gene polymorphism is a marker for lupus nephritis activity rather than chronicity or initial disease risk.
Abstract

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