Complement activation in IgA nephropathy

Semin Immunopathol. 2021 Oct;43(5):679-690. doi: 10.1007/s00281-021-00882-9. Epub 2021 Aug 11.


IgA nephropathy pathogenesis is incompletely understood, and this limits the development of disease-specific biomarkers and effective therapies. Evidence of complement activity in IgA nephropathy is well established. However, a growing body of research indicates complement activity is an important contributor to IgA nephropathy pathology. In particular, multiple associations have been identified between complement alternative, lectin and terminal pathway proteins and IgA nephropathy severity. Recently, we have also gained insight into possible mechanisms that could link glomerular IgA deposition, complement activity, glomerular inflammation and disease severity. Ongoing clinical trials of therapeutic complement inhibitors will provide insight into the importance of complement activity to IgA nephropathy pathogenesis. Further research into mechanisms of complement activity is essential to improving our understanding and management of patients with IgA nephropathy.

Keywords: Complement; IgA nephropathy; Immunology; Pathology.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Complement Activation
  • Complement System Proteins / metabolism
  • Glomerulonephritis, IGA* / diagnosis
  • Glomerulonephritis, IGA* / etiology
  • Glomerulonephritis, IGA* / metabolism
  • Humans
  • Immunoglobulin A / metabolism
  • Kidney Glomerulus / metabolism


  • Immunoglobulin A
  • Complement System Proteins