The humoral pattern recognition receptor PTX3 is stored in neutrophil granules and localizes in extracellular traps

• Published in: The Journal of experimental medicine Vol. 204; no. 4; pp. 793 - 804
• Main Authors: Jaillon, Sébastien, Peri, Giuseppe, Delneste, Yves, Frémaux, Isabelle, Doni, Andrea, Moalli, Federica, Garlanda, Cecilia, Romani, Luigina, Gascan, Hugues, Bellocchio, Silvia, Bozza, Silvia, Cassatella, Marco A, Jeannin, Pascale, Mantovani, Alberto
• Format: Journal Article
• Language: English
• Published: United States The Rockefeller University Press 16-04-2007
• Subjects: Animals; Aspergillus fumigatus; C-Reactive Protein - deficiency; C-Reactive Protein - genetics; C-Reactive Protein - metabolism; Cells, Cultured; Cytoplasmic Granules - metabolism; Extracellular Space - metabolism; Gene Expression Regulation; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophils - cytology; Neutrophils - metabolism; Protein Binding; Serum Amyloid P-Component - deficiency; Serum Amyloid P-Component - genetics; Serum Amyloid P-Component - metabolism
• ISSN: 0022-1007; 1540-9538; 1892-1007
• DOI: 10.1084/jem.20061301

The long pentraxin (PTX) 3 is produced by macrophages and myeloid dendritic cells in response to Toll-like receptor agonists and represents a nonredundant component of humoral innate immunity against selected pathogens. We report that, unexpectedly, PTX3 is stored in specific granules and undergoes release in response to microbial recognition and inflammatory signals. Released PTX3 can partially localize in neutrophil extracellular traps formed by extruded DNA. Eosinophils and basophils do not contain preformed PTX3. PTX3-deficient neutrophils have defective microbial recognition and phagocytosis, and PTX3 is nonredundant for neutrophil-mediated resistance against Aspergillus fumigatus. Thus, neutrophils serve as a reservoir, ready for rapid release, of the long PTX3, a key component of humoral innate immunity with opsonic activity.