Am. J. Respir. Crit. Care Med.,
Volume 161, Number 3, March 2000, 718-722
Influenza Virus Inhibits Lysozyme Secretion by Sputum
Neutrophils in Subjects with Chronic Bronchial Sepsis
GERALD
PANG,
ROBERT
CLANCY,
MA
CONG,
MARIA
ORTEGA,
REN
ZHIGANG,
and
GLEN
REEVES
Faculty of Medicine and Health Sciences, University of Newcastle; and Hunter Immunology Unit, Royal Newcastle Hospital,
Newcastle, Australia
Neutrophils are central to the control of infection within the bronchial mucosa. To determine whether
the link between bacterial and viral infection in the respiratory tract can be partly explained by acute
reduction of neutrophil function, we examined the influence of influenza virus on lysozyme secretion
by sputum neutrophils obtained from patients with bronchiectasis. Sputum neutrophils infected with
influenza A virus had a significantly reduced capacity to secrete lysozyme but not myeloperoxidase.
Influenza virus A strains were more effective in inhibiting lysozyme secretion than were influenza B
virus strains. Reduction of bactericidal activity was similarly reduced by different strains of influenza A
virus, but an influenza virus B strain had no effect. Our results show that downregulation of sputum
neutrophil function characterized by lysozyme secretion and bactericidal activity could contribute to
reduction in the capacity to control bacterial colonization in the respiratory tract following influenza
virus infection. Pang G, Clancy R, Cong M, Ortega M, Zhigang R, Reeves G. Influenza virus inhibits lysozyme secretion by sputum neutrophils in subjects with chronic bronchial sepsis.
