Abstract: TH-PO366

RNA Sequencing of Enriched Collecting Duct Specific Cells Reveals Novel Immune Cell Signature in Intercalated and Principal Cells

Session Information

Category: Cell Biology

  • 201 Cell Signaling, Oxidative Stress

Authors

  • Saxena, Vijay, Nationwide Children's Hospital , Columbus, Ohio, United States
  • Schwaderer, Andrew L., The Ohio State University, Westerville, Ohio, United States
  • Ketz, John, Nationwide Children''s Hospital, Columbus, Ohio, United States
  • Hains, David S., Riley Children's Hospital, Indianapolis, Indiana, United States
Background

The collecting duct is well known to be involved with acid-base and water balance, but other functions are relatively unexplored. Recently we generated two reporter mice models to enrich collecting duct specific principal cell (PC) and intercalated cell (IC) and reported targeted gene expression of anti-microbial peptide genes because these cells are the "1st responders" to ascending pathogens. In this study, we performed global unbiased gene expression profiling on enriched ICs and PCs using RNA sequencing.

Methods

In this study, we performed global unbiased gene expression profiling on enriched ICs and PCs using RNA sequencing and performed pathway analysis with Ingenuity software.

Results

Lineage marker expression analysis indicated enrichment of ICs and PCs. IC lineage marker (Atp6v1b1, Slc4a1 and Slc26a4) normalized read counts were 11-27 fold higher in ICs compared to non-ICs, while PC lineage marker (Aqp2, Elf2, Scnn1a, Scnn1b and Scnn1g) normalized read counts were 24-198 fold higher in PCs compared to non-PCs. In direct comparison between ICs and PCs, IC marker expression was 2-3 fold higher in ICs while PC marker expression was 2-fold higher in PCs. The genes upregulated in ICs included innate immune receptor Il1r1, tight junction protein such as Cldn4 and electrolyte exchanges such as Slc8a1. Ingenuity analysis of upstream regulators revealed ICs involvement in proliferation, inflammation and anti-bacterial response. PC's top predicted upstream regulators with a Z-score > 2 were TGFβ1, TP53, and cisplatin (a drug which is reported to cause polyuria). The top PC functions are cellular assembly and organization, and organismal survival. In direct comparison, both IC and PCs revealed overlapping innate immune function with expression of nod like receptors such as Nlrp6, Nod1, Nod2, toll like receptor such ad Tlr1,Tlr3 and Tlr12, interleukin receptor such as Il13ra1, Il17r, Il1r1, Il15r, and chemokine receptor such as Cxcl10, Cxcl12, Cxcr4 - which are shown to be involved in response to pathogen challenge. Both cells had expression of beta defensin 1, 11, 29, and 42, as well as secretogranin V (Scg V), while lipocalin 2 (Lcn2) was also highly enriched in principal cells.

Conclusion

This study identifies collecting duct cells as innate immune effector cells with overlapping function.

Funding

  • NIDDK Support