analysis of beta-cell gene expression reveals inflammatory signaling and evidence of dedifferentiation following human islet isolation and cultureβ细胞基因表达的分析,将揭示炎症信号和去分化的证据后人类胰岛细胞分离和文化.pdfVIP

Analysis of Beta-Cell Gene Expression Reveals Inflammatory Signaling and Evidence of Dedifferentiation following Human Islet Isolation and Culture 1,2 1,2 1,2 1,2 3 1,2 Sarita Negi , Arif Jetha , Reid Aikin , Craig Hasilo , Rob Sladek , Steven Paraskevas * 1 Human Islet Transplantation Laboratory, McGill University Health Centre, Montreal, Quebec, Canada, 2 Department of Surgery, McGill University, Montreal, Quebec, Canada, 3 McGill University and Genome Quebec Innovation Centre, Montreal, Quebec, Canada Abstract The stresses encountered during islet isolation and culture may have deleterious effects on beta-cell physiology. However, the biological response of human islet cells to isolation remains poorly characterized. A better understanding of the network of signaling pathways induced by islet isolation and culturing may lead to strategies aimed at improving islet graft survival and function. Laser capture microdissection (LCM) was used to extract beta-cell RNA from 1) intact pancreatic islets, 2) freshly isolated islets, 3) islets cultured for 3 days, and changes in gene expression were examined by microarray analysis. We identified a strong inflammatory response induced by islet isolation that continues during in-vitro culture manifested by upregulation of several cytokines and cytokine-receptors. The most highly upregulated gene, interleukin-8 (IL-8), was induced by 3.6-fold following islet isolation and 56-fold after 3 days in culture. Immunofluorescence studies showed that the majority of IL-8 was produced by beta-cells themselves. We also observed that several pancreas-specific transcription factors were down-regulated in cultured islets. Concordantly, several pan