Hyalinosis and Ym1/Ym2 Gene Expression in the Stomach and Respiratory Tract of 129S4/SvJae and Wild-Type and CYP1A2-Null B6,129 Mice

• Published in: The American journal of pathology Vol. 158; no. 1; pp. 323 - 332
• Main Authors: Ward, Jerrold M., Yoon, Michung, Anver, Miriam R., Haines, Diana C., Kudo, Gen, Gonzalez, Frank J., Kimura, Shioko
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 2001; ASIP; American Society for Investigative Pathology
• Subjects: Animal Models; Animals; beta-N-Acetylhexosaminidases - genetics; beta-N-Acetylhexosaminidases - metabolism; Biological and medical sciences; Blotting, Northern; Blotting, Western; Chemotactic Factors, Eosinophil - genetics; Chemotactic Factors, Eosinophil - metabolism; Cytochrome P-450 CYP1A2 - genetics; Cytochrome P-450 CYP1A2 - metabolism; Electrophoresis, Polyacrylamide Gel; Female; Gene Expression Regulation; Hyalin - metabolism; Lectins - genetics; Lectins - metabolism; Male; Medical sciences; Metabolic diseases; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Mice, Mutant Strains; Microscopy, Electron; Miscellaneous; Other metabolic disorders; Respiratory System - metabolism; Respiratory System - pathology; RNA, Messenger - genetics; RNA, Messenger - metabolism; Stomach - metabolism; Stomach - pathology; Stomach - ultrastructure; Survival Analysis; Immunohistochemistry; Stomach; Animal model; Respiratory disease; Cytochrome P450; Deficiency; Rodentia; Metabolic diseases; Electron microscopy; Enzymopathy; Hyalinosis; Respiratory tract; Pathology; Vertebrata; Mammalia; Mouse; Animal; Digestive diseases; Molecular biology; Gastric disease
• ISSN: 0002-9440; 1525-2191
• DOI: 10.1016/S0002-9440(10)63972-7

The C57BL/6, 129, and B6,129 mouse strains or stocks have been commonly used to generate targeted mutant mice. The pathology of these mice is not well characterized. In studies of these aging mice, we found high incidences of hyalinosis (eosinophilic cytoplasmic change) in the glandular stomach, respiratory tract, bile duct, and gall bladder of B6,129 CYP1A2-null and wild-type mice as well as in both sexes of the background 129S4/SvJae strain. The gastric lesions of the glandular stomach were found in 95.7% of female CYP1A2-null mice as well as in 45.7% of female 129S4/SvJae animals. The eosinophilic protein isolated from characteristic hyaline gastric lesions was identified as Ym2, a member of the chitinase family. Immunohistochemistry, using rabbit polyclonal antibodies to oligopeptides derived from the Ym1 sequence, detected focal to diffuse reactivity within both normal and abnormal nasal olfactory and respiratory epithelium, pulmonary alveolar macrophages, bone marrow myeloid cells, and the squamous epithelium of the forestomach and epithelium of the glandular stomach. Alveolar macrophages in acidophilic pneumonia, a major cause of death of aging 129 mice, and in mice with the me mutation also were highly immunoreactive. The possible cause of this protein excess in gastric and other lesions and its possible functions are discussed.