Nuclear factor-kappa B activation in the nasal polyp epithelium: relationship to local cytokine gene expression.
OBJECTIVE
A panel of cytokines has been found to be important for eosinophil accumulation and activation in nasal polyps. The aims of this study were to ascertain whether the activation of nuclear factor-kappa B (NF-kappaB) occurred in the polyp epithelium, and to examine the relationship between the degree of activation and local cytokine gene expression.


METHODS
Nasal polyp specimens were obtained from 26 untreated patients. The proportion of nuclear translocation of the NF-kappaB p50 subunit in the polyp epithelium was quantitatively analyzed by a combination of fluorescent immunohistochemistry and a laser scanning confocal microscope image system. The levels of GM-CSF, IL-5, IL-8, IL-16, and eotaxin mRNA expression in the same speci-mens were measured using reverse transcription-polymerase chain reaction.


RESULTS
Both cytoplasmic and nuclear localization of the p50 subunit was observed mainly in the epithelial layer in all specimens. The percentages of epithelial cells with nuclear translocation ranged from 4.5% to 40.5% (median, 18%). Significant correlations were observed between the degree of epithelial NF-kappaB activation and the levels of IL-8, IL-16, and eotaxin mRNA expression (r = 0.468, 0.47, and 0.739, respectively).


CONCLUSIONS
The activation of NF-kappaB in the nasal polyp epithelium is responsible for the recruitment of inflammatory cells, particularly eosinophils, through the initiation of the transcriptional pathway of the related cytokines. The increased NF-kappaB activity in the polyp epithelium may reflect hypersensitivity to unknown stimuli.
Takeno
Sachio
S
Department of Otolaryngology, Hiroshima University School of Medicine, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8551, Japan. Sachio.Takeno@ma2.seikyou.ne.jp
Hirakawa
Katsuhiro
K
Ueda
Tsutomu
T
Furukido
Kyosuke
K
Osada
Rika
R
Yajin
Koji
K
D002908:Chronic Disease; D016207:Cytokines / Q000235:genetics*; D004802:Eosinophilia / Q000276:immunology / Q000473:pathology; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D007958:Leukocyte Count; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D016328:NF-kappa B / Q000502:physiology*; D052002:NF-kappa B p50 Subunit; D009298:Nasal Polyps / Q000276:immunology* / Q000473:pathology; D009669:Nose Neoplasms / Q000276:immunology* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics; D012852:Sinusitis / Q000276:immunology / Q000473:pathology
D016207:Cytokines; D016328:NF-kappa B; D052002:NF-kappa B p50 Subunit; D012333:RNA, Messenger