title: Manipulation of cell sorting within mesenchymal stromal cell-islet cell multicellular spheroids.
abstract: Colocalization of islets with immunoprivileged cell types such as mesenchymal stromal cells (MSCs) is a potentially multifaceted and adaptive approach to islet protection. We attempted to colocalize MSCs with islets by creating single-celled suspensions of MSCs and cells from dissociated islets on top of arrays of round-bottomed wells. Segregation between islet-derived cells and MSCs was observed within 3 days. When ROCK inhibitor Y-27632-containing medium was used during the preparation of MSC/islet coaggregates, coaggregates sorted into core-shell structures with islet-derived cells occupying the exterior while MSCs occupied the core. Immunostaining revealed that MSC-derived regions transition from expression of N-cadherin, vimentin, and CD44 to expression of E-cadherin, while pan-cadherin staining indicated reallocation of cadherins to cell borders, and shear-based cohesion measurements pointed to increased cohesive strength. The switch suggests that MSC-islet cohesion improved due to the greater degree of cell-cell adhesive compatibility. Functional evaluation of MSC-islet coaggregates confirmed normal insulin secretory function and partial suppression of anti-CD3-activated splenocyte proliferation. These findings demonstrate that manipulation of cell-cell interactions can be harnessed to control spheroid architecture in MSC-islet coaggregates, and this study also provides the basis for future islet therapies.
authors.affiliation: Institute for Frontier Medical Sciences, Kyoto University , Kyoto, Japan .
authors.forename: Ian T
authors.initials: IT
authors.lastname: Hoffecker
authors.forename: Hiroo
authors.initials: H
authors.lastname: Iwata
mesh_terms: D000577:Amides / Q000494:pharmacology; D000818:Animals; D015820:Cadherins / Q000378:metabolism; D002449:Cell Aggregation / Q000187:drug effects; D002469:Cell Separation / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology / Q000276:immunology; D008810:Mice, Inbred C57BL; D011725:Pyridines / Q000494:pharmacology; D018874:Spheroids, Cellular / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D059008:Time-Lapse Imaging; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000577:Amides; D015820:Cadherins; D007328:Insulin; D011725:Pyridines; C108830:Y 27632; D054460:rho-Associated Kinases