Expression of Toll-like receptor 9 in nose, peripheral blood and bone marrow during symptomatic allergic rhinitis

• Published in: Respiratory research Vol. 8; no. 1; p. 17
• Main Authors: Fransson, Mattias, Benson, Mikael, Erjefält, Jonas S, Jansson, Lennart, Uddman, Rolf, Björnsson, Sven, Cardell, Lars-Olaf, Adner, Mikael
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 2007; BioMed Central; BMC
• Subjects: Adolescent; Adult; Allergic; Biological Markers; Biological Markers: metabolism; Biomarkers - metabolism; Bone Marrow; Bone Marrow - metabolism; Clinical Medicine; Female; Humans; Klinisk medicin; Leukocytes; Leukocytes - metabolism; Lungmedicin och allergi; Male; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; metabolism; Middle Aged; Nasal Mucosa; Nasal Mucosa - metabolism; Respiratory Medicine and Allergy; Rhinitis; Rhinitis, Allergic, Seasonal - metabolism; Seasonal; Seasonal: metabolism; Toll-Like Receptor 9; Toll-Like Receptor 9 - metabolism
• ISSN: 1465-993X; 1465-9921; 1465-993X; 1465-9921
• DOI: 10.1186/1465-9921-8-17

Allergic rhinitis is an inflammatory disease of the upper airway mucosa that also affects leukocytes in bone marrow and peripheral blood. Toll-like receptor 9 (TLR9) is a receptor for unmethylated CpG dinucleotides found in bacterial and viral DNA. The present study was designed to examine the expression of TLR9 in the nasal mucosa and in leukocytes derived from different cellular compartments during symptomatic allergic rhinitis. The study was based on 32 patients with seasonal allergic rhinitis and 18 healthy subjects, serving as controls. Nasal biopsies were obtained before and after allergen challenge. Bone marrow, peripheral blood and nasal lavage fluid were sampled outside and during pollen season. The expression of TLR9 in tissues and cells was analyzed using immunohistochemistry and flow cytometry, respectively. TLR9 was found in several cell types in the nasal mucosa and in different leukocyte subpopulations derived from bone marrow, peripheral blood and nasal lavage fluid. The leukocyte expression was generally higher in bone marrow than in peripheral blood, and not affected by symptomatic allergic rhinitis. The widespread expression of TLR9 in the nasal mucosa along with its rich representation in leukocytes in different compartments, demonstrate the possibility for cells involved in allergic airway inflammation to directly interact with bacterial and viral DNA.