We have previously reported that multi-cellular heteroaggregates comprising murine pancreatic α (αTC1.6) and β (MIN6-m9) cell lines spontaneously acquired islet-like architecture and displayed higher insulin secretion rates. However, the mechanisms of self-organization remain unclear. The objective of this study is to examine the possibility that a sugar chain participates in the mutual recognition of the cells during reconstitution of the islet-like structure in vitro. Using a lectin-binding assay, we identified Erythrina cristagalli agglutinin (ECA), which particularly recognizes the β-galactoside structure on the surfaces of MIN6-m9 cells. The self-organization of αTC1.6 and MIN6-m9 was obstructed using ECA-bound MIN6-m9 cells. Lactose neutralized the ECA's inhibitory effect on the autonomous rearrangement of αTC1.6 and MIN6-m9 cells, indicating that the inhibition of cell arrangement by ECA was mediated via β-galactoside. We concluded that a β-galactoside sugar chain was central to the reconstitution of the pancreatic islet-like architecture in vitro.
Keywords: ConA, concanavalin A; DMEM, Dulbecco's Modified Eagle's Medium; ECA, Erythrina cristagalli agglutinin; FITC, fluorescein isothiocyanate; Islet reconstitution; Islet-like structure; LCA, Lens culinaris agglutinin, α-d-mannosyl group; Lectin; MAA, Maackia amurensis agglutinin; MC, methylcellulose; RCA, Ricinus communis agglutinin; SSA, Sambucus sieboldiana agglutinin; Sugar chain; UEA, Ulex europaeus agglutinin; WGA, wheat germ agglutinin; β-Galactoside.