Single cell transcriptome analysis defines heterogeneity of the murine pancreatic ductal tree

Abstract

Lineage tracing using genetically engineered mouse models is an essential tool for investigating cell-fate decisions of progenitor cells and biology of mature cell types, with relevance to physiology and disease progression. To study disease development, an inventory of an organ's cell types and understanding of physiologic function is paramount. Here, we performed single-cell RNA sequencing to examine heterogeneity of murine pancreatic duct cells, pancreatobiliary cells, and intrapancreatic bile duct cells. We isolated duct cells within the murine pancreas using a Dolichos biflorus agglutinin (DBA) lectin sorting strategy that labels all pancreatic duct cell types. Our data suggested the substructure of murine pancreatic duct cells is compartmentalized into three subpopulations. We describe an epithelial-mesenchymal transitory axis in our three pancreatic duct subpopulations and identify SPP1 as a regulator of this fate decision as well as human duct cell de-differentiation. Our results further identify functional heterogeneity within pancreatic duct subpopulations by elucidating a role for Geminin in accumulation of DNA damage in the setting of chronic pancreatitis. Our findings implicate diverse functional roles for subpopulations of pancreatic duct cells in maintenance of duct cell identity and disease progression and establish a comprehensive road map of murine pancreatic duct cell, pancreatobiliary cell, and intrapancreatic bile duct cell homeostasis.

Single-cell transcriptomics reveals a conserved metaplasia program in pancreatic injury

“…Consistent with our sequencing data, we identified the expression of SPEM and chief cell markers in injured pancreata, whereas expression is absent from the normal pancreas (Figure 3B, S5C). To confirm that this phenotype is ADM-specific, we compared our mucin/ductal population to normal pancreatic ductal scRNA-seq datasets and found SPEM signatures to be restricted to ADM (Figure S6E-F, File S2) 11, 29 . Finally, we conducted SEM on ADM and identified cells with admixed mucin and digestive enzyme-containing granules, similar to the phenotype of SPEM associated with gastric injury (Figure 3C).…”

Single-Cell Transcriptomics Reveals a Conserved Metaplasia Program in Pancreatic Injury

“…To confirm that this phenotype is ADM-specific, we compared our mucin/ductal population to the EYFP-negative ductal cells in our dataset as well as published normal pancreatic ductal scRNA-seq datasets and found that the injury-induced ADM signature is distinct (Supplementary Figure 3, Supplementary Figure 4E and F, Supplementary Table 3). 11,30 Finally, we conducted SEM on ADM and identified cells with admixed mucin and digestive enzyme-containing granules, similar to the phenotype of SPEM associated with gastric injury (Figure 3C).…”

On the Origin of Pancreatic Cancer: Molecular Tumor Subtypes in Perspective of Exocrine Cell Plasticity

“…Very recent single-nucleus and single-cell RNA sequencing studies have shed light on the existence of different subsets of duct cells in both human and mouse tissues. 31,59,60 For example, a small subpopulation with higher expression of genes linked to mucin secretion and a larger subpopulation showing higher expression of typical duct cell markers such as CFTR and SLC4A4 were noticed by Chiang et al 31 Qadir et al 60 reported high heterogeneity within the duct cell population with a rather continuous change in differentiation states. While new studies continue to arrive, 59 it will be important considering the relationship between the different RNA expression clusters and their relevance in homeostatic and perturbed conditions of the pancreas.…”

“… 30 Qadir et al 60 reported high heterogeneity within the duct cell population with a rather continuous change in differentiation states. While new studies continue to arrive, 59 it will be important considering the relationship between the different RNA expression clusters and their relevance in homeostatic and perturbed conditions of the pancreas.…”