Innate immune induction and influenza protection elicited by a response-selective agonist of human C5a

• Published in: PloS one Vol. 7; no. 7; p. e40303
• Main Authors: Sanderson, Sam D, Thoman, Marilyn L, Kis, Kornelia, Virts, Elizabeth L, Herrera, Edgar B, Widmann, Stephanie, Sepulveda, Homero, Phillips, Joy A
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 06.07.2012; Public Library of Science (PLoS)
• Subjects: Analysis; Animal models; Animals; Antigen-Presenting Cells - immunology; Antigen-Presenting Cells - virology; Antigens; Biology; Cancer; Chemokines; Chemokines - metabolism; Complement C5a - agonists; Complement component C5a; Cytokines; Cytokines - metabolism; Dendritic cells; Dose-Response Relationship, Drug; Drug dosages; Drug resistance; Effector cells; Female; Fungi; Health aspects; Human behavior; Humans; Immunity, Innate - drug effects; Immunologic Factors - administration & dosage; Infections; Inflammation; Influenza; Influenza A; Influenza A virus - immunology; Influenza, Human - immunology; Influenza, Human - prevention & control; Insufflation; Killer cells; Kinetics; Laboratory animals; Leukocytes (neutrophilic); Lung - immunology; Lung - metabolism; Lung - pathology; Lung - virology; Macrophages, Alveolar - immunology; Macrophages, Alveolar - virology; Male; Medicine; Mice; Mice, Inbred C57BL; Mortality; Mucosa; Neutrophils; Oligopeptides - administration & dosage; Pandemics; Pathogens; Respiratory diseases; Rodents; Veterinary Science; United States > US; California
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0040303

The anaphylatoxin C5a is an especially potent mediator of both local and systemic inflammation. However, C5a also plays an essential role in mucosal host defense against bacterial, viral, and fungal infection. We have developed a response-selective agonist of human C5a, termed EP67, which retains the immunoenhancing activity of C5a at the expense of its inflammatory, anaphylagenic properties. EP67 insufflation results in the rapid induction of pulmonary cytokines and chemokines. This is followed by an influx of innate immune effector cells, including neutrophils, NK cells, and dendritic cells. EP67 exhibits both prophylactic and therapeutic protection when tested in a murine model of influenza A infection. Mice treated with EP67 within a twenty-four hour window of non-lethal infection were significantly protected from influenza-induced weight loss. Furthermore, EP67 delivered twenty-four hours after lethal infection completely blocked influenza-induced mortality (0% vs. 100% survival). Since protection based on innate immune induction is not restricted to any specific pathogen, EP67 may well prove equally efficacious against a wide variety of possible viral, bacterial, and fungal pathogens. Such a strategy could be used to stop the worldwide spread of emergent respiratory diseases, including but not limited to novel strains of influenza.