Project description:This study explores histone modification dynamics in acute pancreatitis. Sprague-Dawley rats were intraperitoneally injected twice with L-arginine (2.5 g/kg, 1-hour interval) to induce acute pancreatitis. Pancreatic tissues were harvested after 48 hours. CUT&Tag was performed using anti-H3K18LA antibody (IP) and corresponding input control to assess promoter-associated chromatin changes in the inflamed pancreas.
Project description:Autoimmune pancreatitis (AIP) is a recently identified disease of the pancreas with unknown etiology and antigens. The aim of this study was to determine new target antigens and differentially regulated genes and proteins by means of transcriptomics and proteomics and to validate them in patients with autoimmune pancreatitis. Here we report a distinct downregulation at the RNA and protein level of pancreatic proteases (anionic trypsinogen, cationic trypsinogen, mesotrypsinogen, elastase IIIB) and pancreatic stone protein in autoimmune pancreatitis in comparison to alcohol-induced chronic pancreatitis.
Project description:We profiled the genome-wide distribution of H3K18la in samples originating from 6 different in vitro and in vivo mouse samples, representing 3 tissues: embryonic stem cells, macrophages and skeletal muscle as well as in human skeletal muscle and compared them to the profiles of other well-established histone modifications as well as gene expression patterns. Globally, we found that H3K18la profiles resemble H3K27ac profiles better than any other investigated hPTM, including H3K4me3, but that they do not copy them. For all samples, H3K18la marked active CGI promoters of highly expressed genes which were remarkably shared across the different mouse tissues and which contained many housekeeping genes. Promoter H3K18la levels correlated positively to both H3K27ac and H3K4me3 levels as well as to gene expression levels. In addition, we found that H3K18la is enriched at tissue-type specific, active enhancers, which are particularly tissue-type-specific, especially when compared to the H3K18la-marked promoter regions. Accordingly, enhancer H3K18la levels correlate positively to the expression of their nearest genes. Additionally, genes closest to enhancers with high H3K18la levels predominantly consist of tissue-type specific marker genes. Overall, we showed that H3K18la is not only a marker for active promoters, but that it also marks active enhancers, and this both in embryonic tissues and differentiated tissues, and both in mouse and in human.
Project description:We profiled the genome-wide distribution of H3K18la in samples originating from 6 different in vitro and in vivo mouse samples, representing 3 tissues: embryonic stem cells, macrophages and skeletal muscle as well as in human skeletal muscle and compared them to the profiles of other well-established histone modifications as well as gene expression patterns. Globally, we found that H3K18la profiles resemble H3K27ac profiles better than any other investigated hPTM, including H3K4me3, but that they do not copy them. For all samples, H3K18la marked active CGI promoters of highly expressed genes which were remarkably shared across the different mouse tissues and which contained many housekeeping genes. Promoter H3K18la levels correlated positively to both H3K27ac and H3K4me3 levels as well as to gene expression levels. In addition, we found that H3K18la is enriched at tissue-type specific, active enhancers, which are particularly tissue-type-specific, especially when compared to the H3K18la-marked promoter regions. Accordingly, enhancer H3K18la levels correlate positively to the expression of their nearest genes. Additionally, genes closest to enhancers with high H3K18la levels predominantly consist of tissue-type specific marker genes. Overall, we showed that H3K18la is not only a marker for active promoters, but that it also marks active enhancers, and this both in embryonic tissues and differentiated tissues, and both in mouse and in human.
Project description:In this study, we found that H3K18la level is elevated in adipose stem and progenitor cells of facial infiltrating lipomatosis (FIL-ASPCs). To further explore the potential functional significance of H3K18la in FIL, we performed genome-wide cleavage under targets and tagmentation (CUT&Tag) analysis to identify candidate genes regulated by H3K18la in FIL-ASPCs and CON-ASPCs. Following CUT&Tag, H3K18la-associated DNAs were amplified using non-biased conditions, labeled, and sequenced with Illumina NovaSeq 150PE.
Project description:BACKGROUND & AIMS: Acinar cells produce digestive enzymes that impede transcriptomic characterization of the exocrine pancreas. Thus, single-cell RNA-sequencing (scRNA-seq) studies of the pancreas underrepresent acinar cells relative to histological expectations, and a robust approach to capture pancreatic cell responses in disease states is needed. We sought to innovate a method that overcomes these challenges to accelerate study of the pancreas in health and disease. METHODS: We introduce FixNCut, a scRNA-seq approach where tissue is reversibly fixed with dithiobis(succinimidyl propionate) prior to dissociation and single-cell preparation. We apply FixNCut to an established mouse model of acute pancreatitis, validate findings using GeoMx whole transcriptome atlas (WTA) profiling, and integrate our data with prior studies to benchmark our method in both mouse and human pancreas datasets. RESULTS: FixNCut achieves unprecedented definition of challenging pancreatic cells including acinar and immune populations in homeostasis and acute pancreatitis, and identifies changes in all major cell types during injury and recovery. We define the acinar transcriptome during homeostasis and acinar-to-ductal metaplasia and establish a unique gene set to measure deviation from normal acinar identity. We characterize pancreatic immune cells, and analysis of T-cell subsets reveals a polarization of the homeostatic pancreas towards type-2 immunity. We report immune responses during acute pancreatitis and recovery, including early neutrophil infiltration, expansion of dendritic cell subsets, and a substantial shift in the transcriptome of macrophages due to both resident macrophage activation and monocyte infiltration. CONCLUSIONS: FixNCut preserves pancreatic transcriptomes to uncover novel cell states during homeostasis and following pancreatitis, establishing a broadly applicable approach and reference atlas for study of pancreas biology and disease.