Asthmatic bronchial epithelium activated by the proteolytic allergen Der p 1 increases selective dendritic cell recruitment.
BACKGROUND
Airway dendritic cells (DCs) are crucial for allergen-induced sensitization and inflammation in allergic asthma. After allergen challenge, an increased number of DCs is observed in airway epithelium from patients with allergy.


OBJECTIVE
Because Der p 1, a cysteine protease allergen from Dermatophagoides pteronyssinus , induces chemokine production by bronchial epithelial cells (BECs), the purpose of this investigation was to evaluate the capacity of BEC exposed to Der p 1 to recruit DCs.


METHODS
Chemotactic activity of BEAS-2B, a bronchial epithelial cell line, and BECs from nonatopic controls and patients with allergic asthma was evaluated on the migration of precursors, immature and mature monocyte-derived DCs (MDDCs), and CD34 + -derived Langerhans cells (LCs).


RESULTS
C-C chemokine ligand (CCL)-2, CCL5, and C-X-C chemokine ligand 10 production by BEAS-2B and BEC was increased after Der p 1 exposure, whereas the proenzyme proDer p 1 devoid of enzymatic activity had no effect. Der p 1 stimulation of BEAS-2B and BEC from both groups increased significantly the recruitment of MDDC precursors, depending on CCL2, CCL5, and C-X-C chemokine ligand 10 production. In a reconstituted polarized epithelium, apical application of Der p 1 enhanced MDDC precursor migration into the epithelial layer. Moreover, Der p 1 stimulation of BEC from patients with asthma but not from controls increased the migration of LC precursors, mainly dependent on CCL20 secretion. No migration of immature and mature DCs was observed.


CONCLUSIONS
These data confirmed that BECs participate in the homeostasis of the DC network present within the bronchial epithelium through the secretion of chemokines. In allergic asthma, upregulation of CCL20 production induced LC recruitment, the role of which remains to be determined.
Pichavant
Muriel
M
INSERM U416, IFR 17, Institut Pasteur, 1 rue du Professeur Calmette, BP 245, 59019 Lille Cedex, France.
Charbonnier
Anne-Sophie
AS
Taront
Solenne
S
Brichet
Anne
A
Wallaert
Benoît
B
Pestel
Joel
J
Tonnel
André-Bernard
AB
Gosset
Philippe
P
D000328:Adult; D039741:Antigens, Dermatophagoides / Q000276:immunology / Q000494:pharmacology*; D060829:Arthropod Proteins; D001249:Asthma / Q000276:immunology*; D001980:Bronchi / Q000276:immunology*; D002460:Cell Line; D018925:Chemokines / Q000378:metabolism; D003546:Cysteine Endopeptidases; D005260:Female; D006801:Humans; D007801:Langerhans Cells / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D020556:Neutrophil Infiltration / Q000187:drug effects / Q000276:immunology; D020545:Respiratory Mucosa / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D013234:Stem Cells / Q000187:drug effects / Q000276:immunology
D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D018925:Chemokines; D003546:Cysteine Endopeptidases; C451162:Dermatophagoides pteronyssinus antigen p 1