Cleavage of annexin A1 by ADAM10 during secondary necrosis generates a monocytic "find-me" signal.

Abstract

Annexin A1 is an intracellular calcium/phospholipid-binding protein that is involved in membrane organization and the regulation of the immune system. It has been attributed an anti-inflammatory role at various control levels, and recently we could show that annexin A1 externalization during secondary necrosis provides an important fail-safe mechanism counteracting inflammatory responses when the timely clearance of apoptotic cells has failed. As such, annexin A1 promotes the engulfment of dying cells and dampens the postphagocytic production of proinflammatory cytokines. In our current follow-up study, we report that exposure of annexin A1 during secondary necrosis coincided with proteolytic processing within its unique N-terminal domain by ADAM10. Most importantly, we demonstrate that the released peptide and culture supernatants of secondary necrotic, annexin A1-externalizing cells induced chemoattraction of monocytes, which was clearly reduced in annexin A1- or ADAM10-knockdown cells. Thus, altogether our findings indicate that annexin A1 externalization and its proteolytic processing into a chemotactic peptide represent final events during apoptosis, which after the transition to secondary necrosis contribute to the recruitment of monocytes and the prevention of inflammation.

• Authors: Karin E Blume, Szabolcs Soeroes, Hildegard Keppeler, Stefan Stevanovic, Dorothee Kretschmer, Maren Rautenberg, Sebastian Wesselborg, Kirsten Lauber
• Journal: Journal of immunology (Baltimore, Md. : 1950) (J Immunol) Vol. 188 Issue 1 Pg. 135-45 (Jan 01 2012) ISSN: 1550-6606 [Electronic] United States
• PMID: 22116825 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Annexin A1
• Chemotactic Factors
• Membrane Proteins
• Amyloid Precursor Protein Secretases
• ADAM Proteins
• ADAM10 Protein
• ADAM10 protein, human

Topics

• ADAM Proteins (genetics, immunology, metabolism)
• ADAM10 Protein
• Amyloid Precursor Protein Secretases (genetics, immunology, metabolism)
• Annexin A1 (genetics, immunology, metabolism)
• Chemotactic Factors (genetics, immunology, metabolism)
• Chemotaxis (genetics, immunology)
• Gene Knockdown Techniques
• HL-60 Cells
• Humans
• Jurkat Cells
• Membrane Proteins (genetics, immunology, metabolism)
• Monocytes (immunology, metabolism, pathology)
• Necrosis (genetics, immunology, metabolism)
• Protein Structure, Tertiary
• Proteolysis
• Signal Transduction (genetics, immunology)
• U937 Cells