Cell-Based Kinase Assays

Protein kinases represent one of the most extensively pursued target families in modern drug discovery, with more than 50 kinase inhibitors approved for clinical use across oncology, immunology, and inflammatory indications. While in vitro biochemical assays using purified kinases provide valuable potency and selectivity data, they cannot fully recapitulate the complexity of the intracellular environment. Cell-based kinase assays bridge this gap by measuring kinase activity, compound engagement, and functional consequences within intact cells, where endogenous cofactors, competing ATP pools, phosphatase activity, and membrane permeability all influence drug behavior. Profacgen offers a comprehensive cell-based kinase assay platform that delivers physiologically relevant data to support lead optimization, mechanism-of-action studies, and translational pharmacology.

What We Offer: Cell-Based Kinase Assay Services

Profacgen provides two complementary cell-based assay strategies designed to evaluate kinase inhibitor potency and selectivity in a native cellular context. Both approaches generate robust, quantitative data that correlate with in vivo efficacy more closely than purified enzyme assays alone.

Assay Principle and Workflow

Cell-based kinase assays measure the functional consequence of kinase inhibition within living cells, capturing compound permeability, metabolic stability, and off-target liabilities that biochemical assays miss. Profacgen follows a rigorous, standardized workflow to ensure reproducibility and regulatory compliance:

1. Cell Line Selection & Engineering: We select or engineer the optimal cell system based on the target kinase and assay format. Options include transient transfection (HEK293), stable knock-in lines, Ba/F3 kinase-dependent proliferation models, and patient-derived or primary cell systems. Cell identity is verified by STR profiling and mycoplasma testing.
2. Assay Development & Validation: For each cell system, we optimize cell density, stimulation conditions (e.g., growth factor, serum), compound treatment duration, and lysis parameters. Z′ factors and signal-to-background ratios are determined to confirm assay robustness.
3. Compound Treatment: Test compounds are prepared as DMSO stock solutions and serially diluted across a concentration range (typically 10-point, half-log dilutions). Cells are treated in 96- or 384-well plates for a defined duration (typically 1–24 hours for phosphorylation assays; 48–72 hours for proliferation assays).
4. Cell Lysis & Sample Processing: Cells are lysed under conditions that preserve phospho-epitopes. For phospho-antibody formats, lysates are transferred to detection plates or processed for western blot. For proliferation assays, viability reagents are added directly to culture wells.
5. Signal Detection: Detection is performed according to the selected readout—luminescence for viability, fluorescence or TR-FRET for phospho-antibody assays, flow cytometry for phospho-flow, or automated imaging for high-content platforms.
6. Data Analysis: Raw signals are normalized to vehicle (DMSO) and positive control (reference inhibitor) wells. Percent inhibition or percent viability is calculated and fitted to a four-parameter logistic model to derive EC₅₀ or IC₅₀ values. For mechanistic studies, pathway activation kinetics and combination indices are computed.

Service Capabilities

Supported Kinase Types

We proudly offer a large selection of kinase targets in cell-based assays:

Applications

Cell-based kinase assays are essential at multiple stages of the drug discovery and development pipeline:

• Kinase inhibitor screening: Primary and secondary screening of small-molecule libraries, natural products, and biologics to identify inhibitors with demonstrable cellular activity, eliminating compounds with poor permeability or metabolic instability.
• Cellular potency determination: Quantitative EC₅₀ / IC₅₀ ranking to prioritize leads and establish structure–activity relationships (SAR) that account for cellular context.
• Pathway activation and intracellular phosphorylation studies: Mapping of compound effects on complete signaling cascades to confirm on-target mechanism, identify compensatory pathway activation, and guide combination therapy design.
• Mechanism-of-action and selectivity profiling: Differentiation of ATP-competitive, allosteric, and covalent inhibitors through cellular kinetics, reversibility, and multi-target profiling.
• Resistance and mutant profiling: Preclinical assessment of compound susceptibility to clinically observed resistance mutations, supporting proactive medicinal chemistry and clinical trial design.
• Translational pharmacology: Correlation of cellular potency with patient-derived models and biomarker strategies to predict clinical efficacy and dosing regimens.

Service Advantages

Deliverables

Upon project completion, clients receive a comprehensive data package including:

• Raw data: Unprocessed plate reader outputs, flow cytometry FCS files, or imaging datasets in standardized formats
• Dose–response curves: Graphical plots with fitted four-parameter logistic curves, including 95% confidence intervals and replicate statistics
• EC₅₀ / IC₅₀ values: Tabulated potency parameters with cell line, assay format, and treatment conditions
• Pathway activation profiles: Phospho-site quantification and signaling node mapping for mechanistic studies
• Study report: Detailed protocol description, quality control metrics, statistical analysis, and interpretive summary prepared by our scientific team

Frequently Asked Questions (FAQs)

For more information about our cell-based kinase assays, please contact us for details. Our tech representatives are available to help you 24 hours a day, Monday through Friday.