Kinetics of inflammatory cytokines in the clearance of non-typeable Haemophilus influenzae from the lung.
Levels of the pro-inflammatory cytokines TNF-alpha and IFN-gamma were measured from the time of infection to the time of complete clearance of non-typeable Haemophilus influenzae (NTHi) from the lung in immune and non-immune rats. Mucosal immunization facilitated production of significant levels of TNF-alpha as early as 30 min post-pulmonary challenge with NTHi in immune animals. Following the peak at 2 h, rapid decline of TNF-alpha levels occurred from the alveolar spaces. Levels of TNF-alpha in non-immunized animals increased at a slower rate, peaked at a lower concentration and were slower to decline. The significantly larger number of macrophages seen in the immune animals at 1 h after bacterial challenge could partially account for the higher levels of TNF-alpha. Interferon-gamma was not detected in immune or non-immune rats at any time point before NTHi clearance after pulmonary challenge. Study of the kinetics of TNF-alpha release demonstrates that immunized animals control the release of pro-inflammatory cytokines more effectively than non-immunized animals for enhanced clearance of bacterial infection from the lungs.
Foxwell
A R
AR
Research Centre for Human and Biomedical Sciences, Faculty of Applied Science, University of Canberra, Australian Capital Territory, Australia.
Kyd
J M
JM
Cripps
A W
AW
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D006192:Haemophilus Infections / Q000276:immunology*; D006193:Haemophilus influenzae / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal; D007371:Interferon-gamma / Q000378:metabolism*; D008168:Lung / Q000378:metabolism / Q000382:microbiology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014611:Vaccination
D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma