Wallac 1420 victor3 5 plate reader

Luciferase enzyme assays were performed using luciferase assay kits (Applied Biosystems, Carlsbad, CA, USA). Cells were plated and treated with DFO or exosomes, as previously described. After 48 h, the wells were washed twice with PBS and lysis solution was added to each well. Cell lysates were then transferred to a microplate. Bioluminescence was measured using a Wallac 1420 VICTOR3 V plate reader (PerkinElmer Life and Analytical Sciences, Shelton, CT, USA).

The 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay (Sigma-Aldrich, St. Louis, MO, USA) was used to determine the cell viability. A total of 5 × 10⁴ cells were seeded and cultivated in each well of 96-well plates for 24 h, followed by treatment with different amounts of TAT-NDUFS8 or NDUFS8-TAT recombinant protein for 48 h. Later, we added 250 μg/mL MTT to the cell culture for 2 h. The resulting yellowish solution was reduced to purple formazan in living cells, and 200 μL dimethyl sulfoxide (DMSO; Scharlau, Sentmenat, Spain) was then added to each well to dissolve the insoluble MTT product into a purplish solution. The cell viability index was measured at 565 nm by a Wallac 1420 VICTOR³ V plate reader (PerkinElmer, Waltham, MA, USA).