Dmem low glucose 1 g l

Immortalized murine osteocalcin expressing cementoblasts (OC/CM), friendly provided by Prof. Somerman^{24 (link)}, were cultured in DMEM low glucose (1 g/L) (Gibco, USA), 10% FCS (Gibco, USA), 100 units/mL of penicillin and 100 µg/mL of streptomycin (Gibco, USA) in cell culture plates under normal cell culture conditions (37 °C, 5% CO₂, water saturated). Cells were trypsinized, centrifuged at 350g, quantified using Counting Chamber “Neubauer improved” and different numbers of cells were seeded in 6-well plates.

Human pancreatic islet (HI) preparations were isolated from heart-beating cadaveric organ donors as previously described [39 (link)] in the Pancreatic Islet Processing Unit of the Diabetes Research Institute (DRI) at the San Raffaele Hospital in Milan, Italy. The use of human specimens (islet preparations discarded from clinical use) was approved by the Institutional Review Board under the “European Consortium for Islet Transplantation (ECIT) human islet distribution program” supported by the Juvenile Diabetes Research Foundation (JDRF) (3-RSC-2016-160-I-X) [40 (link)]. The genetically engineered human pancreatic β cell line EndoC-βH1 [41 (link)] was grown in DMEM-low glucose (1 g/L) (Gibco, New York, NY, USA), 2% BSA (Sigma), 50 μM 2-mercaptoethanol (Sigma, St. Louis, MO, USA), 10 mM nicotinamide (Sigma), 5.5 μg/mL transferrin (Gibco), 6.7 ng/mL sodium selenite (Sigma), 1% Pen/Strep.