RT Journal Article
SR Electronic
T1 Th2-associated immunity to bacteria in teenagers and susceptibility to asthma
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 509
OP 516
DO 10.1183/09031936.00184109
VO 36
IS 3
A1 E.M. Hollams
A1 B.J. Hales
A1 C. Bachert
A1 W. Huvenne
A1 F. Parsons
A1 N.H. de Klerk
A1 M. Serralha
A1 B.J. Holt
A1 S. Ahlstedt
A1 W.R. Thomas
A1 P.D. Sly
A1 P.G. Holt
YR 2010
UL http://erj.ersjournals.com/content/36/3/509.abstract
AB Bacterial colonisation of the airways is associated with increased risk of childhood asthma. Immunoglobulin (Ig)E against bacterial antigens has been reported in some asthmatics, suggesting a role for bacterial-specific type-2 immunity in disease pathogenesis. We aimed to investigate relationships between bacterial-specific IgE amongst teenagers and asthma susceptibility. We measured titres of IgE against Haemophilus influenzae, Streptococcus pneumoniae and Staphylococcus aureus in 1,380 teenagers, and related these to asthma symptomatology and immunophenotypes. IgE titres against S. aureus-derived enterotoxins were highest amongst atopics and were associated with asthma risk. Surprisingly, IgE titres against H. influenzae and S. pneumoniae surface antigens were higher, not stratified by atopy and independently associated with decreased asthma risk. The positive association between type-2 immunity to S. aureus and asthma phenotypes probably reflects IgE-mediated effector cell activation via enterotoxin super antigens which are secreted in soluble form. The contrasting benign nature of type-2 immunity to H. influenzae and S. pneumoniae antigens may reflect their lower availability in soluble forms that can crosslink IgE receptors. We theorise that instead they may be processed by antigen presenting cells and presented to type-2 memory cells leading to mucosal secretion of interleukin (IL)-4/IL-13, a mechanism widely recognised in other tissues to attenuate T-helper-1 associated bacterial-induced inflammation.