Nh2 ps nps

PS NPs and NH₂-PS NPs were acquired from Sigma–Aldrich (Sigma-Aldrich, St. Louis, MI, USA). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), 2′,7′-dichlorodihydrofluorescein di-acetate (DCF), JC1, and LDH Detection Kit were purchased from Beyotime Institute of Biotechnology (Jiangsu, China). TRIzol reagent was acquired from Takara (Takara Biochemicals, Dalian, China). The ReverTra Ace^® qPCR RT Kit and SYBR^® Green Realtime PCR Master Mix were from Toyobo (Tokyo, Japan). All oligonucleotide primers were synthesized in Sangon Biotech (Sangon, Shanghai, China).

The MEF cells were kindly provided by Noboru Mizushima (Tokyo Dental and Medical University, Tokyo, Japan), and 1321N1 cells were obtained from the European Collection of Cell Cultures (ECACC). Cells were routinely cultured in Dulbecco's Modified Eagle's Medium Glutamax (DMEM) (Life Technologies) supplemented with 1% glutamine, 10% heat-inactivated fetal bovine serum (Life Technologies) and 50 units ml⁻¹ of penicillin and 50 µg ml⁻¹ of streptomycin in a 37°C incubator with 95% air/5% CO₂ atmosphere. Cells were grown to 70–80% confluency before treatment. Fifty nanometres of blue fluorescently labelled NH₂-PS NPs was purchased from Sigma-Aldrich and their characterizations can be found in [9 ,15 (link)]. NH₂-PS NPs were used at 50 µg ml⁻¹ for all studies, as has been optimized previously for studies of cell death [9 ,14 ,15 (link),33 (link)].