B6-hOSM Mouse

The OSM gene (Oncostatin M) encodes a secreted cytokine, Oncostatin M, which is a pleiotropic protein belonging to the leukemia inhibitory factor/oncostatin-M (LIF/OSM) family. This protein is expressed in various immune cells, including activated T lymphocytes, macrophages, and neutrophils, as well as in other tissues like endothelial cells, osteoblasts, and smooth muscle cells ^[1]. OSM plays diverse functions, acting as a growth regulator that can inhibit the proliferation of certain tumor cell lines, stimulate proliferation of others (e.g., AIDS-KS cells), and regulate the production of other cytokines like IL-6, G-CSF, and GM-CSF. Its activities are mediated through two receptor complexes: Type I (gp130 and LIFRβ) and Type II (gp130 and OSMRβ), primarily activating the JAK/STAT, MAPK, JNK, and PI3K/AKT signaling pathways ^[2]. OSM is implicated in a wide array of diseases, contributing to inflammatory conditions such as arthritis (rheumatoid and osteoarthritis), inflammatory bowel disease, lung and skin diseases (e.g., psoriasis, asthma), cardiovascular diseases (e.g., atherosclerosis), and liver diseases (e.g., fibrosis) ^[3]. It also exhibits a complex role in various cancers, sometimes inhibiting tumor growth in early stages or in specific cell lines, while promoting tumorigenesis, epithelial-mesenchymal transition (EMT), invasion, and metastasis in more advanced cancers like breast, cervical, ovarian, pancreatic, and lung cancers. Deficiency in OSM has also been linked to severe bone marrow failure syndromes ^[4].

The B6-hOSM mouse is a humanized model, constructed by replacing the coding sequences of the endogenous mouse Osm gene with the coding sequences of the human OSM gene. B6-hOSM mice can be used for research into the pathogenesis of inflammatory conditions such as arthritis (rheumatoid and osteoarthritis), inflammatory bowel disease, lung and skin diseases (e.g., psoriasis, asthma), cardiovascular diseases (e.g., atherosclerosis), liver diseases (e.g., fibrosis), various cancers, and bone marrow failure syndromes, as well as for the screening, development, and safety evaluation of OSM-targeted drugs.