The DEK nuclear autoantigen is a secreted chemotactic factor

Area of Science:

• Molecular Biology
• Immunology
• Cell Biology

Background:

• The DEK protein is a nuclear DNA-binding protein involved in gene regulation.
• DEK has been identified as an autoantigen implicated in various cellular processes.

Purpose of the Study:

• To investigate the extracellular role and secretion of the DEK protein.
• To determine if DEK functions as a signaling molecule in inflammatory conditions.

Main Methods:

• Analysis of DEK secretion from macrophages.
• Detection of DEK in synovial fluid from juvenile arthritis patients.
• Investigating DEK's chemoattractant properties for immune cells.

Main Results:

• DEK is actively secreted by macrophages and found in synovial fluid of juvenile arthritis patients.
• DEK secretion is regulated by specific signaling molecules and inhibited by certain drugs.
• DEK is secreted both freely and within exosomes, and it attracts neutrophils, CD8+ T cells, and NK cells.

Conclusions:

• The DEK autoantigen, previously considered strictly nuclear, is secreted and functions as an extracellular chemoattractant.
• These findings suggest a direct role for DEK in mediating inflammatory responses.
• DEK's secretion in exosomes represents a novel mechanism for extracellular protein transport.