title: Size-based separation and collection of mouse pancreatic islets for functional analysis.
abstract: Islet size has recently been demonstrated to be an important factor in determining human islet transplantation outcomes. In this study, a multi-layered microfluidic device was developed and quantified for size-based separation of a heterogeneous population of mouse islets. The device was fabricated using standard soft lithography and polydimethylsiloxane (PDMS). Size-based separation was first demonstrated via injection of a heterogeneous population of glass beads between 50-300 microm in diameter which were separated into five sub-populations based on their diameter. Next, a heterogeneous population of mouse pancreatic islets, between 50-250 microm in diameter was separated into four sub-populations. Throughout this process the islets remained intact without any signs of damage, as indicated by cell viability staining. Islet glucose-stimulated insulin secretion of each sub-population of islets was also evaluated demonstrating that islets smaller than 150 microm have superior stimulation indexes (SI) compared to islets larger than 150 microm. In this study, we found that islets between 100 microm and 150 microm in diameter had the greatest SI value in a heterogeneous population of islets.
authors.affiliation: Department of Bioengineering, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Ki-Hwan
authors.initials: KH
authors.lastname: Nam
authors.forename: Wang
authors.initials: W
authors.lastname: Yong
authors.forename: Tricia
authors.initials: T
authors.lastname: Harvat
authors.forename: Adeola
authors.initials: A
authors.lastname: Adewola
authors.forename: Shesun
authors.initials: S
authors.lastname: Wang
authors.forename: Jose
authors.initials: J
authors.lastname: Oberholzer
authors.forename: David T
authors.initials: DT
authors.lastname: Eddington
mesh_terms: D000818:Animals; D002470:Cell Survival; D005898:Glass / Q000737:chemistry; D005947:Glucose / Q000494:pharmacology; D006112:Gravitation; D006801:Humans; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D051379:Mice; D046210:Microfluidic Analytical Techniques; D008863:Microspheres; D009929:Organ Size; D015203:Reproducibility of Results
chemical_list: D007328:Insulin; D005947:Glucose