Mast cell surfaceome characterization reveals CD98 heavy chain is critical for optimal cell function.

Area of Science:

• Immunology
• Cell Biology
• Proteomics

Background:

• Mast cells play critical roles in various diseases, necessitating a thorough understanding of their surface proteins.
• The complete surface proteome of mast cells remains largely uncharacterized.

Purpose of the Study:

• To comprehensively characterize the mast cell surface proteome.
• To identify novel surface proteins and elucidate their functions in mast cell biology.

Main Methods:

• Enrichment of glycosylated surface proteins from mouse bone marrow-derived cultured mast cells (BMCMCs).
• Identification of proteins using mass spectrometry.
• Validation of novel surface proteins via quantitative PCR and flow cytometry.
• Gene editing using CRISPR/Cas9 to disrupt target genes.

Main Results:

• Identified 1270 proteins, with 378 localized to the plasma membrane.
• Key protein classes included small GTPases, receptors, and transporters.
• Disruption of the Slc3a2 gene significantly reduced CD98 heavy chain (CD98hc) expression, adhesion, and proliferation.

Conclusions:

• Glycoprotein enrichment and mass spectrometry are effective for identifying novel mast cell surface molecules.
• CD98hc is a significant cell surface protein involved in mast cell function.