Staphylococcus aureus enterotoxin B facilitates allergic sensitization in experimental asthma.
BACKGROUND
Staphylococcus aureus Enterotoxin B (SEB) has immunomodulatory effects in allergic airway disease. The potential contribution of SEB to the sensitization process to allergens remains obscure.


OBJECTIVE
In order to study the effects of staphylococcal-derived toxins on the sensitization to ovalbumin (OVA) and induction of allergic airway inflammation, we have combined the nasal application of OVA with different toxins.


METHODS
Nasal applications of OVA and saline, SEA, SEB, toxic shock syndrome toxin (TSST)-1, protein A or lipopolysaccharide (LPS) were performed on alternate days from day 0 till 12. On day 14, mice were killed for the evaluation of OVA-specific IgE, cytokine production by mediastinal lymph node (MLN) cells and bronchial hyperreactivity (BHR) to inhaled metacholine. The effect of SEB on dendritic cell (DC) migration and maturation, and on T cell proliferation was evaluated.


RESULTS
Concomitant endonasal application of OVA and SEB resulted in OVA-specific IgE production, whereas this was not found with SEA, TSST-1, protein A, LPS or OVA alone. Increased DC maturation and migration to the draining lymph nodes were observed in OVA/SEB mice, as well as an increased T cell proliferation. Bronchial inflammation with an influx of eosinophils and lymphocytes was demonstrated in OVA/SEB mice, together with hyperresponsiveness and the production of IL-4, IL-5, IL-10 and IL-13 by MLN stimulated with OVA.


CONCLUSIONS
Our data demonstrate that SEB facilitates sensitization to OVA and consecutive bronchial inflammation with features of allergic asthma. This is likely due to augmentation of DC migration and maturation, as well as the allergen-specific T cell proliferation upon concomitant OVA and SEB application.
Huvenne
W
W
Upper Airways Research Laboratory, Department of Otorhinolaryngology, Ghent University Hospital, Ghent, Belgium. Wouter.Huvenne@UGent.be
Callebaut
I
I
Plantinga
M
M
Vanoirbeek
J A J
JA
Krysko
O
O
Bullens
D M A
DM
Gevaert
P
P
Van Cauwenberge
P
P
Lambrecht
B N
BN
Ceuppens
J L
JL
Bachert
C
C
Hellings
P W
PW
D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000517:prevention & control; D016535:Bronchial Hyperreactivity / Q000517:prevention & control*; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D003713:Dendritic Cells / Q000187:drug effects* / Q000276:immunology; D004195:Disease Models, Animal; D004768:Enterotoxins / Q000494:pharmacology*; D006801:Humans; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C
D004768:Enterotoxins; C031818:enterotoxin B, staphylococcal