Assigning immunoglobulin class from single-cell transcriptomes in IgA1-secreting versus membrane subpopulations

Biotechniques. 2021 Feb;70(2):89-99. doi: 10.2144/btn-2020-0044. Epub 2020 Dec 14.

Abstract

IgA nephropathy (IgAN) is an autoimmune disease characterized by renal glomerular immunodeposits enriched for galactose-deficient IgA1 (Gd-IgA1; autoantigen) with the corresponding IgG autoantibodies. Despite the known contribution of Gd-IgA1 to IgAN, little is known concerning IgA1-secreting subpopulations responsible for autoantigen production. The goal of this study is to identify IgA1-secreting and membrane subpopulations from single-cell transcriptomic analysis. We developed a novel single-cell analytics workflow to discern cells expressing IgA1 secreted isoform or membrane-bound isoform. Multiple approaches were compared to assess immunoglobulin-isotype identity in single cells, and multiple immunoglobulin heavy-chain genes expressed in the same cells were found. To better identify specific immunoglobulin heavy-chain transcripts, we merged a software platform called Alteryx with the existing single-cell R toolkit program Seurat. This process allowed for improved calls on IgA1-secreting subpopulations based on secreting versus membrane splice-variant expression levels.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Glycosylation
  • Humans
  • Immunoglobulin A* / classification
  • Transcriptome*

Substances

  • Immunoglobulin A