AlphaLISA SureFire Ultra Human and Mouse Total p70 S6K Detection Kit, 500 Assay Points

Total-AlphaLISA SureFire Ultra two-plate assay protocol

The two-plate protocol involves culturing and treating the cells in a 96-well plate before lysis, then transferring lysates into a 384-well OptiPlate™ plate before the addition of Total-AlphaLISA SureFire Ultra detection reagents. This protocol enables cell viability and confluence to be monitored. In addition, lysates from a single well can be used to measure multiple targets.

Total-AlphaLISA SureFire Ultra one-plate assay protocol

Detection of Total target protein with AlphaLISA SureFire Ultra reagents can be performed in a single plate used for culturing, treatment, and lysis. No washing steps are required. This HTS designed protocol allows for miniaturization while maintaining robust AlphaLISA SureFire Ultra quality.

MCF7 cells were seeded in a 96-well plate (40,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO₂. The cells were treated with increasing concentrations of rapamycin for 2 hours before the addition of 10 μg/mL insulin for 30 minutes.

After treatment, the cells were lysed with 100 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). Phospho (Thr389) and Total p70 S6K levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 4,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.

As expected, treatment with rapamycin resulted in a dose-dependent decrease in Phospho (Thr389) p70 S6K levels while Total levels remained unchanged.

MCF7 cells were seeded in a 96-well plate (40,000 cells/well) in complete medium, and incubated overnight at 37°C, 5% CO₂. The cells were treated with increasing concentrations of silmitasertib for 24 hours.

After treatment, the cells were lysed with 200 µL of Lysis Buffer for 10 minutes at RT with shaking (350 rpm). Phospho (Thr389) and Total p70 S6K levels were evaluated using respective AlphaLISA SureFire Ultra assays. For the detection step, 10 µL of cell lysate (approximately 2,000 cells) was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at RT. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.

As expected, treatment with silmitasertib resulted in a dose-dependent decrease in Phospho (Thr389) p70 S6K levels while Total levels remained unchanged.

Versatility of p70 S6K Total assay in various cell lines

Adherent cells were grown to confluency in a T175 flask at 37°C, 5% CO₂, and were lysed with Lysis Buffer at a density of 0.5 x 10⁶ cells/mL. Suspension cells were harvested, washed in HBSS and lysed with Lysis Buffer at 1.6 x 10⁶ cells/mL.

Total p70 S6K levels were evaluated using the AlphaLISA SureFire Ultra assay. For the detection step, 10 µL of cell lysate (5,000 adherent and 16,000 suspension cells) were transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor Mix and incubated for 1 hour at RT. Finally, 5 µL of Donor Mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.

Total p70 S6K expression was detected in a wide range of human and mouse cell lines.

Assay sensitivity - cell lysate dilution

Positive control lysate was prepared from MCF7 cells cultured to confluence in T175 flasks in complete medium. Cells were treated with 500 µg/mL insulin for 30 minutes and then lysed in 20 mL of Lysis Buffer.

Lysates were serially diluted in Lysis Buffer and assayed for Phospho (Thr389) and Total p70 S6K levels using respective AlphaLISA SureFire Ultra kits. For the detection step, 10 µL of lysate was transferred into a 384-well white OptiPlate, followed by 5 µL of Acceptor mix and incubated for 1 hour at room temperature. Finally, 5 µL of Donor mix was then added to each well and incubated for 1 hour at RT in the dark. The plate was read on an Envision using standard AlphaLISA settings.

Approximate number of cells/datapoint is indicated on the graph. The dotted line represents assay background. The assay can detect Total p70 S6K down to 200 cells.