Complement is activated in the upper respiratory tract during influenza virus infection

• Published in: The American review of respiratory disease Vol. 143; no. 5 Pt 1; p. 1062
• Main Authors: Bjornson, A B, Mellencamp, M A, Schiff, G M
• Format: Journal Article
• Language: English
• Published: United States 01-05-1991
• Subjects: Adult; Complement Activation - immunology; Complement C3a - analysis; Complement C5a - analysis; Female; Humans; Influenza, Human - immunology; Male; Nasal Cavity - immunology; Pilot Projects; Radioimmunoassay; Specimen Handling; Therapeutic Irrigation
• ISSN: 0003-0805
• DOI: 10.1164/ajrccm/143.5_pt_1.1062

The purpose of this pilot study was to determine whether complement is activated in the upper respiratory tract during experimental influenza virus infection in human volunteers. Seven subjects were challenged with influenza A/Bethesda/1/85 (H3N2), and four subjects received placebo. C3a and C5a concentrations were measured by radioimmunoassay in nasal lavage fluids before challenge and for 8 days after challenge. A significant increase (p less than 0.05) in C3a and C5a concentrations was demonstrated in lavage fluids from subjects who developed influenza illness as compared with uninfected control subjects and infected subjects who remained asymptomatic. Maximal levels of C3a and C5a were detected during the recovery phase of illness. These results suggest that complement is activated in the airway in response to influenza illness.