Rtca technology

The growth, proliferation and adhesion kinetics of Vero cells were determined using RTCA technology (ACEA Biosciences, San Diego, CA USA) as previously described with some minor modifications [18 (link)]. Briefly, 50 μl of EMEM supplemented with 10 % FBS (cell culture medium) was placed in each well of the E-plate 96 (gold-microelectrode array integrated E-plate; ACEA Biosciences, San Diego, CA USA). E-plate 96 was then connected to the system to obtain background impedance readings. This was to ensure that all wells of E-plate 96 and the connections were in good condition so as to avoid compromising the interpretation of the results. Serial dilutions of 2.0 × 10⁴, 1.8 × 10⁴ and 1.5 × 10⁴ cells in 50 μl were prepared, four replicates in each of the concentrations. These serial dilutions of cell suspensions were added to the wells containing 50 μl of culture medium. The E-plates were incubated at room temperature for 30 min in a laminar flow cabinet and then placed on the RTCA SP Station located in an incubator at 37 °C for continuous impedance recording. CI values measured by continuous impedance recordings every 2 minutes reflected the cell activities.

The growth, proliferation, and adhesion kinetics of HEK293 cells were determined using RTCA technology (ACEA Biosciences, San Diego, CA, USA). Fifty microliters of DMEM supplemented with 10% HI‐FBS and 50 μg/ml gentamicin (cell culture medium) was loaded in each well of the E‐plate 96 (gold‐microelectrode array integrated E‐plate; ACEA Biosciences). E‐plate 96 was then connected to the system to obtain background impedance readings. Around 1.5 × 10⁴ cells in 50 μl were added to the wells containing 50 μl of culture medium. The E‐plates were placed on the RTCA SP Station located in a 37°C, 5% CO₂ tissue culture incubator for continuous impedance recording. The cell index values measured by continuous impedance recordings every 5 min are proportional to the number of adherent cells. After 16–17 h, cells were transfected as described below, and for each of the conditions, four replicates were done. The assay was conducted for 40 h.

The growth, proliferation and adhesion kinetics of Vero cells were determined using RTCA technology (ACEA Biosciences, San Diego, CA, USA) and we followed their protocol (AbuBakar et al., 2014[2 (link)]; Kho et al., 2015[5 (link)]). Briefly, 50 μl of EMEM supplemented with 10 % FBS (cell culture medium) was placed in each well of the E-plate 96 (gold-microelectrode array integrated E-plate; ACEA Biosciences, San Diego, CA USA). E-plate 96 was then connected to the system to obtain background impedance readings. This was to ensure that all wells of E-plate 96 and the connections were in good condition so as to avoid compromising the interpretation of the results. Serial dilutions of 2.0 × 10 ⁴, 1.8 × 10⁴ and 1.5 × 10⁴ cells in 50 μl were prepared, with four replicates for each of the concentrations. These serial dilutions of cell suspensions were then added to the wells containing 50 μl of culture medium. The E-plates were incubated at room temperature for 30 min in a laminar flow cabinet and then placed on the RTCA SP Station located in an incubator at 37 °C for continuous impedance recording. CI values as measured by continuous impedance recordings every 2 min reflected the cellular activities.