Screening Peptides that Activate MRGPRX2 using Engineered HEK Cells.

Area of Science:

• Pharmacology
• Immunology
• Biochemistry

Background:

• Identifying specific ligands for cell receptors like Mas related G-protein receptor-X2 (MRGPRX2) is vital for therapeutic development.
• MRGPRX2 plays a key role in mast cell activation and immune responses.
• Current methods for screening MRGPRX2 ligands are limited by the difficulty and cost of maintaining mast cells in vitro.

Purpose of the Study:

• To develop and validate a robust, cost-effective method for screening peptide libraries against MRGPRX2.
• To utilize MRGPRX2-expressing HEK cells for high-throughput screening.
• To identify key parameters for MRGPRX2 ligand binding and receptor activation.

Main Methods:

• Designed and screened a peptide library using MRGPRX2-expressing HEK cells.
• Employed a calcium-sensitive Fura-2 fluorescent dye to monitor intracellular calcium flux.
• Calculated calcium concentration based on Fura-2 fluorescence ratios.
• Generated peptide library based on PAMP-12 using amino acid truncation and alanine scanning.

Main Results:

• Established a functional high-throughput screening system using MRGPRX2-expressing HEK cells.
• Demonstrated the system's ability to detect MRGPRX2 activation via calcium flux.
• Successfully screened a PAMP-12-based peptide library to identify potential MRGPRX2 ligands.

Conclusions:

• The developed method offers a simple, inexpensive, and robust approach for screening large compound libraries.
• This system facilitates the identification of MRGPRX2-specific ligands and binding domains.
• The method is suitable for high-throughput analysis, accelerating the discovery of new therapeutics targeting MRGPRX2.