title: Insulin secretion dynamics of free and alginate-encapsulated insulinoma cells.
abstract: This study investigates the effect of alginate/poly-L: -lysine/alginate (APA) encapsulation on the insulin secretion dynamics exhibited by an encapsulated cell system. Experiments were performed with the aid of a home-built perfusion apparatus providing a 1 min temporal resolution. Insulin profiles were measured from: (i) murine insulinoma betaTC3 cells encapsulated in calcium alginate/poly-L: -lysine/alginate (APA) beads generated with high guluronic (G) or high mannuoric (M) content alginate, and (ii) murine insulinoma betaTC-tet cells encapsulated in high M APA beads and propagated in the presence and absence of tetracycline. Results show that encapsulation in APA beads did not affect the insulin secretion profile shortly post-encapsulation. However, remodeling of the beads due to cell proliferation affected the insulin secretion profiles; and inhibiting remodeling by suppressing cell growth preserved the secretion profile. The implications of these findings regarding the in vivo function of encapsulated insulin secreting cells are discussed.
authors.affiliation: Chemical & Biomolecular Engineering, Georgia Institute of Technology, 315 Ferst Drive, IBB Building, Room 1306, Atlanta, GA, 30332, USA.
authors.forename: Shing-Yi
authors.initials: SY
authors.lastname: Cheng
authors.forename: Ioannis
authors.initials: I
authors.lastname: Constantinidis
authors.forename: Athanassios
authors.initials: A
authors.lastname: Sambanis