Abstract: PO0194
Novel Immune Defense Cells of the Kidney Epithelia
Session Information
- AKI Mechanisms - 2
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Xu, Katherine, Columbia University Irving Medical Center, New York, New York, United States
- Banlengchit, Run, Columbia University Irving Medical Center, New York, New York, United States
- Levitman, Abraham D., Columbia University Irving Medical Center, New York, New York, United States
- Shen, Tian, Columbia University Irving Medical Center, New York, New York, United States
- Barasch, Jonathan M., Columbia University Irving Medical Center, New York, New York, United States
- Kiryluk, Krzysztof, Columbia University Irving Medical Center, New York, New York, United States
- Sims, Peter A., Columbia University Irving Medical Center, New York, New York, United States
Background
Urinary tract infections (UTIs) are one of the most common bacterial infections worldwide, affecting infant boys, older men, and most prominently, women of all ages. It is predominately caused by uropathogenic E. coli and can lead to urosepsis and kidney failure if untreated. We have found a major role for kidney epithelia, specifically the intercalated cells (IC), that are activated in defense against bacteria. Given the heterogeneity of kidney cell types, we hypothesized that there could be other cells that respond to a UTI.
Methods
We performed 10x Genomics single cell RNA-seq (scRNAseq) of whole kidneys from mice with UTI at 12 hrs and from mice without infection. We also performed scRNAseq of IC from lipopolysaccharide (LPS)-induced mice at 0, 8, and 24 hrs using a novel mRNA profiling method, pooled library amplification for transcriptome expression (PLATE)-seq. We used ROSA26nT-nG;Atp6v1b1Cre mice that activated GFP in IC and subsequently sorted GFP+ cells for PLATE-seq.
Results
scRNAseq across 16 samples from 10 mice (5 UTI-Control pairs) yielded 64,760 cells and resulted in populations of all major kidney cell types, as well as rare populations, i.e., pelvic transitional epithelial cells and double positive (DP) collecting duct cells, which have markers of both intercalated and principal cells. By gene set enrichment analysis, we found that DP cells activated gene sets involved in cell killing and innate immune responses at 12 hrs of UTI. DP cells were also found to be highly transcriptionally active in response to infection in a cross analysis with our dataset from 4-thiouracil-labeled nascent RNAs purified from Atp6v1b1+ cells. scRNAseq on Atp6v1b1+ population after LPS induction (525 cells) further revealed time-dependent activation of immune responses. We found that these IC/DP cells increased Umod expression in both UTI (1.6 fold change; padj=1E-2) and LPS (1.7 fold change; padj=1E-6) analyses. Umod, known to have immune properties, is commonly expressed in the loop of Henle and distal tubule, but may have a novel bacterial defense role in the IC/DP cells.
Conclusion
We found a novel immune defense role of the double positive collecting duct cells in response to UTI. These transcriptionally active cells induce genes involved in cytotoxic and innate immunity and can provide new insights into the epithelial defense of the kidney.
Funding
- NIDDK Support