Ea hy926

Commercial cell lines were obtained from American Type Culture Collection (ATCC, Manassas, USA) and cultivated following the manufacturer's instructions. Accordingly, fibroblasts (human, HGF, PCS-201-018), mature osteoblasts (human, U2OS, HTB-96), fetal pre-osteoblasts (human, hFOB, CRL-11372) and endothelial cells (human, ea.hy926, CRL-2922) were selected to test specimens' cytocompatibility in vitro. U2OS and ea.hy926 were grown in Dulbecco's Modified Eagle Medium (DMEM, Sigma Aldrich) 10% FBS (Gibco, Invitrogen, USA) and 1% antibiotics, HGF were cultivated in alpha-modified Eagle's minimum essential medium (α-MEM, Sigma Aldrich) 10% FBS, 1% antibiotics while for hFOB a 50:50 mix of MEM and Ham's F12 (MEM/F12, 1:1,Sigma Aldrich) 10% FBS (Invitrogen, USA), 1% antibiotics and 3 mg/ml neomycin (G418, Sigma) was used. All cells were grown until a 90% confluence and then collected by enzymatic digestion (trypsin/EDTA) prior to each assay. Moreover, in order to preserve the original primary phenotype, HGF and hFOB were applied until passage 10.

Human retinal pigment epithelial cell line, ARPE-19 (ATCC number CRL-2302), was cultured in DMEM-F12 (Gibco^TM 31330), 10% fetal bovine serum (FBS), 100 U/ml penicillin and 100 µg/ml streptomycin (all from Thermo Fisher Scientific, Waltham, MA, USA). HeLa (CRM-CCL-2), EA.hy926 (CRL-2922), SH-SY5Y (CRL-2266) and U-87 MG (HTB-14) cell lines were cultured in DMEM (D7777, Sigma-Aldrich, Saint Louis, MO, USA), 10% FBS, 100 U/ml penicillin and 100 µg/ml streptomycin. All the cells were cultured in a cell incubator at 37°C and 5% CO₂.