Genome-wide mRNA profiling of adult human pancreatic beta and duct cells in comparison to other human tissues

Aims: establishment of reference samples to investigate gene expression selective for endocrine or ductal-exocrine cells within the adult human pancreas. To this end, human islet endocrine cells, FACS-enriched in insulin+ cells, (n=3) and human exocrine ductal cells (n=2) are compared on Affymetrix HG133A platform with duplicate hybridizations of a panel of other primary human tissues. The microarray analysis was performed on 3 pools of human beta cell-enriched cell fractions, isolated from 10 non-selected donor organs, and 2 pools of duct cell-enriched fractions obtained from 6 non-selected donor pancreases. The cells were suspension-cultured for 2-3 weeks along standard procedures and with no specific treatment prior to FACS-sorting and RNA extraction. The average composition of human beta cell-preparations was 55 ± 13% insulin+ cells, 13±8% glucagon+ cells and 21 ±7% non-granulated cells. Pancreatic duct cells-enriched preparations contained 85 ±7% cytokeratin 19+ cells with 4 ± 1% insulin+ cells and 6 ±4% glucagon+ cells and were isolated as described by Heimberg H. et al.( Diabetes 2001,49: 571-579 ). Pancreatic cell mRNA profiles were compared to those of a panel of other human primary tissues (n=2 biological replicates).