MUB40 Binds to Lactoferrin and Stands as a Specific Neutrophil Marker

• Published in: Cell chemical biology Vol. 25; no. 4; pp. 483 - 493.e9
• Main Authors: Anderson, Mark C., Chaze, Thibault, Coïc, Yves-Marie, Injarabian, Louise, Jonsson, Friederike, Lombion, Naelle, Selimoglu-Buet, Dorothée, Souphron, Judith, Ridley, Caroline, Vonaesch, Pascale, Baron, Bruno, Arena, Ellen T., Tinevez, Jean-Yves, Nigro, Giulia, Nothelfer, Katharina, Solary, Eric, Lapierre, Valérie, Lazure, Thierry, Matondo, Mariette, Thornton, David, Sansonetti, Philippe J., Baleux, Françoise, Marteyn, Benoit S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 19.04.2018; Cell Press
• Subjects: Adult; Animals; Biochemistry, Molecular Biology; biomarker; Biomarkers; Carbocyanines; Dysentery, Bacillary; Female; Fluorescent Dyes; Guinea Pigs; Humans; imaging; Immunology; Inflammation; Lactoferrin; Life Sciences; Mice; Mice, Inbred C57BL; Middle Aged; MUB40; neutrophil; Neutrophils; Peptides; Rabbits; Shigella; lactoferrin; MUB40; biomarker; neutrophil; imaging; MUB
• ISSN: 2451-9456; 2451-9456
• DOI: 10.1016/j.chembiol.2018.01.014

Neutrophils represent the most abundant immune cells recruited to inflamed tissues. A lack of dedicated tools has hampered their detection and study. We show that a synthesized peptide, MUB40, binds to lactoferrin, the most abundant protein stored in neutrophil-specific and tertiary granules. Lactoferrin is specifically produced by neutrophils among other leukocytes, making MUB40 a specific neutrophil marker. Naive mammalian neutrophils (human, guinea pig, mouse, rabbit) were labeled by fluorescent MUB40 conjugates (-Cy5, Dylight405). A peptidase-resistant retro-inverso MUB40 (RI-MUB40) was synthesized and its lactoferrin-binding property validated. Neutrophil lactoferrin secretion during in vitro Shigella infection was assessed with RI-MUB40-Cy5 using live cell microscopy. Systemically administered RI-MUB40-Cy5 accumulated at sites of inflammation in a mouse arthritis inflammation model in vivo and showed usefulness as a potential tool for inflammation detection using non-invasive imaging. Improving neutrophil detection with the universal and specific MUB40 marker will aid the study of broad ranges of inflammatory diseases. [Display omitted] •MUB40 is a 40-amino-acid peptide that interacts with neutrophil lactoferrin•MUB40 labels neutrophil-specific (β1), tertiary (β2), and secretome (γ) granules•RI-MUB40 is a proteolysis-resistant version of MUB40•Neutrophilic inflammation is revealed in vivo with RI-MUB40 systemic injection MUB40 is a universal and specific marker of mammalian neutrophils. MUB40 interacts with lactoferrin, stored in specific (β1), tertiary (β2), and secretome (γ) granules secreted upon stimulation. Neutrophil detection in inflamed or infected tissues is facilitated by MUB40 peptides conjugated to fluorophores. Neutrophilic inflammation detection may be envisaged by combining MUB40 with non-invasive imaging.