Expression of mucins in mucoid otitis media.
A hallmark of mucoid otitis media (MOM, i.e., chronic otitis media with mucoid effusion) is mucus accumulation in the middle ear cavity, a condition that impairs transduction of sounds in the ear and causes hearing loss. The mucin identities of mucus and the underlying mechanism for the production of mucins in MOM are poorly understood. In this study, we demonstrated that the MUC5B and MUC4 were major mucins in MOM that formed distinct treelike polymers (mucus strands). The MUC5B and MUC4 mRNAs in the middle ear mucosa with MOM were up regulated 5-fold and 6-fold, compared with the controls. This upregulation was accompanied by the extensive proliferation of the MUC5B- and MUC4-producing cells in the middle ear epithelium. Further study indicated that the mucin hyperproduction was significantly linked to CD4+ and CD8+ T cells and/or CD68+ monocyte macrophages. It suggests that MUC5B and MUC4 expression may be regulated by the products of these cells.
Lin
Jizhen
J
Department of Otolaryngology, Otitis Media Research Center, University of Minnesota School of Medicine, Minneapolis, MN 55455, USA. linxx004@tc.umn.edu
Tsuboi
Yasuhiro
Y
Rimell
Frank
F
Liu
George
G
Toyama
Katsuhiro
K
Kawano
Hirokazu
H
Paparella
Michael M
MM
Ho
Samuel B
SB
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002455:Cell Division; D004432:Ear, Middle / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D015870:Gene Expression / Q000276:immunology; D020397:Goblet Cells / Q000502:physiology; D006801:Humans; D008264:Macrophages / Q000276:immunology; D008679:Metaplasia; D009000:Monocytes / Q000276:immunology; D055264:Mucin-4; D055257:Mucin-5B; D009077:Mucins / Q000235:genetics*; D009092:Mucous Membrane / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D010033:Otitis Media / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D012333:RNA, Messenger / Q000032:analysis
C524658:MUC4 protein, human; C524578:MUC5B protein, human; D055264:Mucin-4; D055257:Mucin-5B; D009077:Mucins; D012333:RNA, Messenger