Histamine release and inflammatory cell infiltration in airway Mucosa in methylene diphenyl diisocyanate (MDI)-induced occupational asthma.
BACKGROUND
Although methylene diphenyl diisocyanate (MDI) is widely used in industries, there have been few studies of the pathogenic mechanisms of MDI-induced occupational asthma (MDI-OA).


METHODS
We performed immunohistochemical analyses, measured inflammatory mediators and cytokines, and quantified histamine release (HR) from peripheral basophils in MDI-OA patients. Thirteen MDI-exposed workers (five MDI-OA, two MDI-induced esoinophilic bronchitis, and six asymptomatic exposed controls, AEC) were enrolled.


CONCLUSIONS
Immunochemical analyses indicated significantly increased anti-eosinophilic cationic protein-stained cells in MDI-OA patients as compared with controls (P < 0.05). Sputum eosinophil cationic protein levels were increased after MDI-specific inhalation challenge test in MDI-OA/EB patients (P < 0.02). Sputum eosinophil counts were highly correlated with IL-8 and MMP-9 levels (P < 0.05 and P < 0.01, respectively). Basophil HR was significantly increased in MDI-OA patients after stimulations with anti-IgG4 and MDI-human serum albumin conjugates (both P < 0.05). Eosinophil activation is a major feature of airway inflammation in MDI-OA patients. Increased HR by MDI may contribute to the pathogenic mechanisms of MDI-OA.
Hur
Gyu-Young
GY
Department of Allergy and Rheumatology, Ajou University School of Medicine, San-5, Wonchun-dong, Youngtong-gu, Suwon 443-721, Korea.
Sheen
Seung-Soo
SS
Kang
Young-Mi
YM
Koh
Dong-Hee
DH
Park
Han-Jung
HJ
Ye
Young-Min
YM
Yim
Hyun-Ee
HE
Kim
Kyoo-Sang
KS
Park
Hae-Sim
HS
D000328:Adult; D001249:Asthma / Q000097:blood / Q000139:chemically induced / Q000276:immunology*; D001491:Basophils / Q000276:immunology / Q000378:metabolism*; D001985:Bronchial Provocation Tests; D001999:Bronchoscopy; D002465:Cell Movement / Q000276:immunology; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006636:Histamine Release / Q000276:immunology*; D006801:Humans; D018928:Immunity, Mucosal; D007150:Immunohistochemistry; D018836:Inflammation Mediators / Q000378:metabolism; D017953:Isocyanates / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects; D020545:Respiratory Mucosa / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D012882:Skin Tests; D013783:Textile Industry; D001559:Benzhydryl Compounds
D016207:Cytokines; D018836:Inflammation Mediators; D017953:Isocyanates; C005969:4,4'-diphenylmethane diisocyanate; D001559:Benzhydryl Compounds