Immunological Pattern in IgA Nephropathy

Int J Mol Sci. 2020 Feb 18;21(4):1389. doi: 10.3390/ijms21041389.


The current gold-standard diagnostic technique for IgA nephropathy (IgAN), the leading form of primary glomerulonephritis, is renal biopsy. CD89 (the main IgA receptor) is expressed on the surface of monocytes and plays a role in disease pathogenesis. Immunocomplexes formed by sCD89 (soluble form) and Gd-IgA1 are related to disease prognosis. We hypothesize that reduced CD89 surface expression on monocytes may be a marker of disease severity. We aimed to analyze leukocyte subpopulations in peripheral blood and CD89 surface expression on monocytes in a prospective study of 22 patients and 12 healthy subjects (HS). Leukocyte subpopulations and CD89 expression were analyzed by flow cytometry. IgAN patients had a higher percentage of activated and effector memory CD4+ and CD8+ T lymphocytes, a lower percentage of transitional B lymphocytes and plasmablasts, and a higher percentage of CD56dimCD16+ NK cells and myeloid dendritic cells compared with HS. Correlations between reduced CD89 expression levels on nonclassical monocytes, histological findings of a poor prognosis on renal biopsy and baseline renal function were observed. IgAN patients show a characteristic immunological pattern in peripheral blood. A reduced expression level of CD89 on nonclassical monocytes identifies patients with a worse renal prognosis.

Keywords: CD89; IgA Nephropathy; biomarkers; monocytes.

MeSH terms

  • Fluorescence
  • Galactose / blood
  • Glomerulonephritis, IGA / immunology*
  • Humans
  • Immunoglobulin A / blood
  • Immunophenotyping
  • Leukocytes / immunology


  • Immunoglobulin A
  • Galactose