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Pancreatic islet transplantation is one of the clinical options for certain types of diabetes. However, difficulty in maintaining islets prior to transplantation limits the clinical expansion of islet transplantations. Our study introduces a dynamic culture platform developed specifically for primary human islets by mimicking the physiological microenvironment, including tissue fluidics and extracellular matrix support. We engineered the dynamic culture system by incorporating our distinctive microwell-patterned porous collagen scaffolds for loading isolated human islets, enabling vertical medium flow through the scaffolds. The dynamic culture system featured four 12 mm diameter islet culture chambers, each capable of accommodating 500 islet equivalents (IEQ) per chamber. This configuration calculates > five-fold higher seeding density than the conventional islet culture in flasks prior to the clinical transplantations (442 vs 86 IEQ/cm 2 ). We tested our culture platform with three separate batches of human islets isolated from deceased donors for an extended period of 2 weeks, exceeding the limits of conventional culture methods for preserving islet quality. Static cultures served as controls. The computational simulation revealed that the dynamic culture reduced the islet volume exposed to the lethal hypoxia (< 10 mmHg) to ~1/3 of the static culture. Dynamic culture ameliorated the morphological islet degradation in long-term culture and maintained islet viability, with reduced expressions of hypoxia markers. Furthermore, dynamic culture maintained the islet metabolism and insulin-secreting function over static culture in a long-term culture. Collectively, the physiological microenvironment-mimetic culture platform supported the viability and quality of isolated human islets at high-seeding density. Such a platform has a high potential for broad applications in cell therapies and tissue engineering, including extended islet culture prior to clinical islet transplantations and extended culture of stem cell-derived islets for maturation., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: This study was performed as a collaborative study between Tokai Hit and Arthur Riggs Diabetes & Metabolism Research Institute of City of Hope. KI, NK, and TT are the employees at Tokai Hit. The remaining authors declare no competing interests.

We reported in 2018 that among several extracellular matrices, fibronectin, type I collagen, type IV collagen, laminin I, fibrinogen, and bovine serum albumin, fibronectin is particularly useful for adhesion of porcine pancreatic tissue. Subsequently, we developed a technology that enables the chemical coating of the constituent motifs of fibronectin onto cell culture dishes. In this experiment, we used islets (purity ≥ 90%), duct epithelial cells (purity ≥ 60%), and acinar cells (purity ≥ 99%) isolated from human pancreas according to the Edmonton protocol published in 2000 and achieved adhesion to the constituent motifs of fibronectin. A solution including cGMP Prodo Islet Media was used as the assay solution. In islets, adhesion was enhanced with the constitutive motifs of fibronectin compared with uncoated islets. In the functional evaluation of islets, insulin mRNA expression and insulin secretion were enhanced by the constitutive motif of fibronectin compared with non-coated islets. The stimulation index was comparable between non-coated islets and fibronectin motifs. In duct epithelial cells, adhesion was mildly promoted by the fibronectin component compared with non-coated component, while in acinar cells, adhesion was inhibited by the fibronectin component compared with the non-coated component. These data suggest that the constitutive motifs of fibronectin are useful for the adhesion of islets and duct epithelial cells.

Background: Single tumors may show heterogeneity, and it is unclear whether biomarker expression in surgical and diagnostic biopsy samples correlates., Materials and Methods: We retrospectively identified lung cancer patients who were diagnosed by biopsy and underwent surgery between January 2007 and October 2010 at the Shimane University Hospital, Shimane, Japan. Thirty-two patients were identified. The expression of four predictive biomarkers was assessed, namely excision repair cross-complementing gene 1 (ERCC1), ribonucleotide diphosphate reductase M1 (RRM1), thymidylate synthase (TS), and class III beta-tubulin (BT). We also compared immunohistochemical staining in diagnostic biopsy and corresponding resected surgical samples., Results: Moderate correlation was seen between the expression of ERCC1, RRM1, TS, and BT in the biopsy and surgical specimens, with r values of 0.512 (p=0.003), 0.411 (p=0.020), 0.475 (p=0.006), and 0.404 (p=0.027), respectively., Conclusion: Assessment of biopsy samples with immunohistochemical staining is a feasible and reliable method for use in clinical decision making., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)