Project description:The goal of this study was to identify changes in the transcriptome that occur following Abca12 gene deletion relative to Control islets
Project description:The goal of this study was to identify changes in the transcriptome that occur following Abca12 gene deletion relative to Control islets
Project description:The pancreas islets RNA expressions were compared between WT (exon2 floxed) mice and Cdh13 KO (exon2 deleted) mice. The islets were isolated from the mice at 8wks old, 14wks old under normal chow diet, and 14wks old under HFD conditions.
Project description:The yield, cell composition, and function of islets isolated from various ages of neonatal pigs were characterized using in vitro and in vivo experimental models. Islets from 7- and 10-day old pigs showed significantly better function both in vitro and in vivo compared to islets from 3- and 5-day old pigs however, the islet yield from 10-day old pigs were significantly less than those obtained from the other pigs. Since islets from 3-day old pigs were used in our previous studies and islets from 7-day old pigs reversed diabetes more efficiently than islets from other groups, we further evaluated the function of these islets post-transplantation. B6 rag-/- mouse recipients of various numbers of islets from 7-day old pigs achieved normoglycemia faster and showed significantly improved response to glucose challenge compared to the recipients of the same numbers of islets from 3-dayold pigs. These results are in line with the findings that islets from 7-day-old pigs showed reduced voltage-dependent K+ (Kv) channel activity and their ability to recover from post-hypoxia/reoxygenation stress. Despite more resident immune cells and immunogenic characteristics detected in islets from 7-day old pigs compared to islets from 3-day old pigs, the combination of anti-LFA-1 and anti- CD154 monoclonal antibodies are equally effective at preventing the rejection of islets from both age groups of pigs. Collectively, these results suggest that islets from various ages of neonatal pigs vary in yield, cellular composition, and function. Such parameters may be considered when defining the optimal pancreas donor for islet xenotransplantation studies.
Project description:The biology of Harlequin Ichthyosis (HI), a devastating skin disorder, caused by loss of function mutations in the gene ABCA12, is poorly understood and to date no satisfactory treatment has been developed. We sought to investigate pathomechanisms of Harlequin Ichthyosis which could lead to the identification of safe and effective treatments to improve patients' quality of life. RNA-Seq analysis using normal skin (n=5) and HI patient skin (n=4) were performed to define the effects of loss of ABCA12. Functional annotation clustering analysis showed changes in three common groups: epidermal differentiation, lipid metabolism and inflammation (innate immunity and IFNγ signalling). In HI patient skin, gene expression of STAT1, STAT3 and Interleukin 36 (IL-36) A and G cytokines was significantly upregulated compared to normal skin, whereas IL-37, an inhibitor of innate immunity, was downregulated. RNA-Seq and functional assays were performed to define the effects of loss of ABCA12, using an engineered CRISPR-Cas9 ABCA12 KO 3D model. Functional annotation clustering analysis showed changes in three common groups: epidermal differentiation, lipid metabolism and inflammation.
Project description:Early postnatal overnutrition causes persistent dysregulation of endocrine pancreas function. We used genome-scale DNA methylation profiling in the suckling-period small litter (SL) mouse model to test whether this occurs via persistent epigenetic changes in pancreatic islets. Although SL islets showed DNA methylation changes directly after weaning and in adulthood, few of these were present at both ages, contrary to our hypothesis. Most interestingly, we discovered that genomic regions that are hypermethylated in exocrine relative to endocrine pancreas tend to gain methylation in islets during aging. Focusing on a subset of genes relevant to β cell function, we showed that these methylation differences are strongly correlated with expression. Together, our results provide the novel insight that DNA methylation changes that occur as islets age indicate an overall epigenetic drift toward the exocrine pancreas epigenome. These concerted shifts in the islet methylome could contribute to the age-associated decline in endocrine pancreas function. Pancreatic islets were isolated from P21/P180 SL or C mice. To ensure purity of islets, 3 rounds of manual picking were performed in each samples. Whole pancreas samples, ~98% of which is exocrine pancreas, were used as exocrine pancreas. There are 5 mice per group.
Project description:Gene expression differences between wild-type, pancreas-specific Hnf4alpha knockout (Hnf4a-pKO), heterozygous Hnf1alpha (Tcf1) (Hnf1aHET), and double mutant (Hnf4a-pKO;Hnf1aHET) mouse pancreatic islets were assesed using amplified RNA samples from islets of matched quality and endocrine purity, obtained from 60-75 day-old control and genetically modified male mice after 48 hours in culture. RNA was amplified using the Affymetrix GeneChIP two-cycle protocol and hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 arrays [Mouse430_2].