CD301 mediates fusion in IL-4-driven multinucleated giant cell formation

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• Multinucleated giant cells (MGCs) are critical in various inflammatory and immune responses.
• The precise molecular mechanisms driving MGC formation remain incompletely understood.
• Identifying key regulators of MGC development is crucial for understanding disease pathogenesis.

Purpose of the Study:

• To identify novel molecular determinants involved in interleukin-4 (IL-4)-induced MGC formation.
• To investigate the role of C-type lectin domain family 10 member (CD301) in MGC development.
• To elucidate the function of CD301 in mediating cell adhesion and fusion.

Main Methods:

• Tandem mass tag-mass spectrometry (TMT-MS) for proteomic analysis of macrophages.
• Interleukin-4 (IL-4) stimulation of mouse RAW264.7 and primary murine macrophages.
• CRISPR/Cas9 gene editing to delete CD301 genes (Mgl1 and Mgl2).
• Functional assays using N-acetylgalactosamine-coated beads to assess cell binding.
• Immunohistochemical analysis of human inflammatory lesions.

Main Results:

• CD301 (CLEC10A) was identified as significantly upregulated in IL-4-stimulated macrophages undergoing MGC formation.
• CD301 was detected in MGCs within human inflammatory biopsy specimens.
• Antibody-mediated inhibition or genetic deletion of CD301 significantly reduced IL-4-induced cell binding and MGC formation.
• Re-expression of CD301 restored MGC formation in knockout cells.

Conclusions:

• CD301 plays a critical role in IL-4-driven MGC formation.
• CD301 mediates intercellular adhesion and fusion, essential processes for MGC development.
• This study identifies CD301 as a key molecular determinant in MGC biology.