Stanford Islet Research Core

Overview

The SIRC (Stanford Islet Research Core) is supported by the Stanford Diabetes Research Center (SDRC). General services include: Islet Isolation, Islet Transplantation, Islet Culture, Islet Perifusion & Islet Hormone Assays. These services can be provided for a variety of sample types including human, mice and pig samples.

The SIRC services are currently only available for Investigators at Stanford University.

Services

Human Islet Procurement

The Stanford IPR Core provides human islets to Stanford investigators for research. These islets are procured through arrangements with multiple high-quality sources, particularly the IsletCore at the University of Alberta (Edmonton), the UCSF Islet Core facility in the UCSF Diabetes Center, the Allegheny Health Network (Pittsburgh), and through in-house isolations.

Blanket MTA with University of Alberta Diabetes Institute (Edmonton) for human islet procurement (starting July 2017)

Our Islet Research Core (IRC) has negotiated a blanket MTA with the University of Alberta Diabetes Institute’s (ADI) Islet Core for human islet procurement for use by our Investigators. The blanket MTA enables researchers at Stanford to procure human islets for their research. This could also include non-islet pancreatic cells. In order to obtain islets through this MTA-enabled streamlined mechanism, each investigator should: 1) contact Seung Kim or Kent Jensen, 2) provide a PTA and copies of their approved protocols (APLAC and/or IRB human subjects exemption covering human islet use in, say, islet transplantation), 3) a copy of their Administrative Panel on Biosafety (APB) Protocol exemption (if necessary) and 4) a brief (1 page) description of their project.

Islet Culture

Mouse or human islet culture is performed in standard RPMI-1640 media with 5 mM or 11 mM glucose at 37°C. As part of this service, the IPR Core provides training for end-users who are interested in islet handling and culture.

Islet Flow Cytometry

Mouse islets: isolated islets are enzymatically dispersed and sorted on a Becton Dickinson FACS ARIAII using flow sorting schemes developed with the user. This can include transgenic mouse islets.

Human islets: isolated islets are enzymatically dispersed and sorted on a Becton Dickinson FACS ARIAII using flow sorting schemes developed with the user. This can be linked to human islets procured through the SDRC IPR Core.

Islet Hormone Assay

Samples generated by islet perifusion and static incubation experiments in the IPR Core are assayed for insulin, glucagon, and/or somatostatin concentration by enzyme-linked immunoassay.

Islet Isolation

The user provides mice. Mouse islets are then isolated by collagenase digestion. Collagenase P in Hank's buffered saline is directly infused into the pancreas through the bile duct. Groups of two pancreata are then digested in 6.7 mL collagenase P for 6-8 min at 37° using a wrist-action shaker. Depending on mouse strain and genetic modification, islets are either handpicked under microscopic guidance or purified using a histopaque gradient. As part of islet isolation service, the IPA Core provides training for end-users who are interested in islet handling and islet picking.

Islet Perifusion

The islet perifusion apparatus is a low-pressure liquid chromatography system that we built in-house from commercially available components. The system consists of two channels where islets are placed into a 1-mL glass column. Each channel is operated independently by a high-precision peristaltic pump. Perifusion media and islet chambers are maintained and stabilized. This system configuration allows us to acquire dynamic hormone secretory profile simultaneously from a set of islets with 1-2 secretagogues per each channel. Perifusate is collected by fraction collectors and samples are then assayed for insulin, or glucagon concentration. End-users receive complete experimental record with raw data, data analysis and graphical representation of each perifusion experiment.

Islet RNA Isolation

For islet RNA isolation, the IPA Core uses industry-standard RNA isolation procedures optimized for small cell volumes, including Ambion-based methods. After isolation, analysis of islet RNA quality is performed in collaboration with the Stanford DRC Genomics and Analysis Core and end-users receive complete report of islet RNA integrity and concentration. This can be linked to the IPR Core islet flow cytometry service.

Islet Transplantation

After scheduling Core staff time online, and face-to-face consultation with IPR Core staff, investigators with approved protocols for animal surgery proved islets (mouse or human) for transplantation in sub-capsular renal sire(s) of suitable mice. Core staff perform the transplantation. Following recovery of recipient mice, post-operative care is provided by the DRC members, with advice from IPR staff.

Static Islet Incubation

Static islet incubation uses a microplate system that allows rapid and cost-effective screening of islet hormone secretion in response to a wide variety of secretagogues and small molecules compounds. End-users receive complete experimental record with raw data, data analysis and graphical representation of each experiment.

Training In Islet Procedures

For islet phenotyping and functional assessment in vitro or after transplantation, the IPR Core provides instruction including training in islet isolation and transplantation, islet culture and specialized assays including insulin ELISA, glucagon ELISA, perfusion and static batch insulin secretion assays, and immunohistology. Users pay for materials including media, disposables and ELISA kits strictly on a cost-recovery basis.