ASN's Mission

ASN leads the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients.

learn more

Contact ASN

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

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: PO1445

Differential Cell Cycle and Kinase Activation in IgA1-Producing Cells from IgAN Patients and Healthy Controls Mediated by Cytokine Stimulation

Session Information

Category: Glomerular Diseases

  • 1202 Glomerular Diseases: Immunology and Inflammation

Authors

  • Reily, Colin, The University of Alabama at Birmingham, Birmingham, Alabama, United States
  • Rizk, Dana, The University of Alabama at Birmingham, Birmingham, Alabama, United States
  • Novak, Jan, The University of Alabama at Birmingham, Birmingham, Alabama, United States
Background

Some cytokines increase production of galactose-deficient IgA1 (Gd-IgA1) in immortalized IgA1-producing cells derived from peripheral blood of patients with IgAN. Previous work has indicated dysregulated cytokine induced signaling may be responsible, but minimal work investigating the overlapping pathways has been performed. Using single-cell transcriptomics, we analyzed pathway responses in immortalized IgA1-secreting cells derived from IgAN patients and healthy controls (HC) before and after response to a mixture of cytokines.

Methods

A mixture of cytokines mimicking those produced by T-follicular helper (Tfh) cells (IL-4, IL-6, IL-21, CD40L; 50 ng/mL) was used to stimulate immortalized IgA1-producing cells for 30 min before single-cell transcriptomic analysis. Gd-IgA1 level was determined by lectin ELISA. Standard data processing using Seurat was performed along with Alteryx for IgA1 separation. Differential markers for genes in unstimulated and stimulated conditions were analyzed for pathway differences using the GSEA MSig database, and kinase-transcription factors were imputed using X2K analysis.

Results

Tfh cytokines mediated overproduction of Gd-IgA1 in IgAN cells but not HC. IgA1-secreting subpopulations were separated, and UMAP was used for unsupervised dimension reduction analysis. Within these UMAP groups, pathway analysis found multiple significant associations, including down-regulation of cell cycle processes (FDR<6X10^-25) in IgAN IgA1 cells compared to an increase in HC (FDR<4.7X10^-6) cells after Tfh cytokine stimulation. Analysis of imputed kinases changed in IgAN stimulated IgA1 cells compared to HC identified MAPK14 (p<1X10^-20 and AKT1 (p<1.1X10^-17), which have been associated with controlling O-glycosylation expression.

Conclusion

Significant changes in imputed kinases previously associated with O-glycosylation were found in IgA1-secreting cells in IgAN compared to HC in response to Tfh cytokine stimulation. When stimulated with cytokines, there were significant decreases in cell cycle and proliferation pathway responses in the IgA1-secreting cells from IgAN vs. HC samples. Further investigation is needed to determine the role of cell cycle and MAPK14 pathways in driving Gd-IgA1 overproduction mediated by cytokine stimulation.

Funding

  • NIDDK Support