Expression and function of toll-like receptors in human basophils.
We investigated the expression and function of a panel of Toll-like receptors (TLRs) in human basophils. Basophil preparations constitutively expressed TLR2, TLR4, TLR9 and TLR10 mRNAs (TLR4 > TLR2 >> TLR9, TLR10). Although TLR mRNA expression in basophils was generally less prominent compared with those in neutrophils and monocytes, basophils expressed significantly higher levels of TLR2 and TLR4 mRNA than eosinophils. Various TLR ligands (Pam3Cys-Ser-Lys4, poly I:C, lipopolysaccharide, R-848, CpG DNA) were tested, but none affected the expression level of adhesion molecule CD11b or the viability of freshly purified basophils. On the other hand, when basophils were pretreated with interferon-gamma before stimulation with TLR ligands, only the TLR4 ligand, lipopolysaccharide, upregulated CD11b expression. However, the surface levels of TLR2 and TLR4 on the interferon-gamma-treated basophils showed no obvious changes. These results suggest that TLR4 on basophils may be involved in the pathogenesis of infection-induced exacerbation of allergic inflammation by modulating basophil functions.
Komiya
Akiko
A
Department of Allergy and Rheumatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
Nagase
Hiroyuki
H
Okugawa
Shu
S
Ota
Yasuo
Y
Suzukawa
Maho
M
Kawakami
Ayako
A
Sekiya
Takashi
T
Matsushima
Kouji
K
Ohta
Ken
K
Hirai
Koichi
K
Yamamoto
Kazuhiko
K
Yamaguchi
Masao
M
D001491:Basophils / Q000276:immunology* / Q000378:metabolism*; D039481:CD11b Antigen / Q000096:biosynthesis; D006801:Humans; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism; D008024:Ligands; D008070:Lipopolysaccharides / Q000276:immunology; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051193:Toll-Like Receptors / Q000276:immunology* / Q000378:metabolism*
D039481:CD11b Antigen; D008024:Ligands; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D051193:Toll-Like Receptors