title: Abnormal expression of Muc5b in Cftr-null mice and in mammary tumors of MMTV-ras mice.
abstract: Gel-forming mucins are large, high molecular weight, and heavily O-glycosylated proteins that are responsible for the rheological properties of mucus gel. Among them, the mucin MUC5B has been implicated in breast cancer and cystic fibrosis. We obtained a new polyclonal serum, named CP1, which was isolated from a rabbit immunized with a mouse Muc5b peptide. The immunoprofile of Muc5b was determined on paraffin-embedded and frozen mouse tissue sections and showed a similar expression pattern in mouse to that in the human. The "nonmammary" mucin Muc5b was detected in all mammary tumors analyzed from MMTV-ras mice, suggesting that the CP1 antibody is a valuable tool for investigating the involvement of this mucin in mammary cancer. We also found that uninfected Cftr( -/- ) mice harbored more Clara cells, which were Muc5b-positive, than did their wild-type control littermates. The number of Muc5b-positive cells increased in Cftr( -/- ) mice infected experimentally with Pseudomonas aeruginosa, and the mice developed mucus plugs in their bronchi and bronchioles with a high frequency of Muc5b content (87%, Cohen's kappa = 0.82; p < 0.0001). These findings suggest that mice genetically deficient in the Cftr gene are predisposed to develop mucus plugs and that MUC5B may provide a valuable target for decreasing mucus viscosity in cystic fibrosis.
authors: Inserm U995, Pôle Recherche, Bât. Huriez, 5ème étage, University Lille 2, 59045 Lille, France.
authors: Hélène
authors: H
authors: Valque
authors: Valérie
authors: V
authors: Gouyer
authors: Marie-Odile
authors: MO
authors: Husson
authors: Frédéric
authors: F
authors: Gottrand
authors: Jean-Luc
authors: JL
authors: Desseyn
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics / Q000378:metabolism; D000918:Antibody Specificity / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D015674:Mammary Neoplasms, Animal / Q000378:metabolism / Q000503:physiopathology*; D008324:Mammary Tumor Virus, Mouse; D051379:Mice; D008810:Mice, Inbred C57BL; D018181:Mice, Inbred CFTR; D018345:Mice, Knockout; D055257:Mucin-5B / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D018631:ras Proteins / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; C524578:MUC5B protein, human; D055257:Mucin-5B; D018631:ras Proteins