Mouse Platelet-Derived Growth Factor-BB (PDGF-BB) is a homodimeric growth factor composed of two PDGF-B chains that plays an important role in cell proliferation, migration, angiogenesis, and tissue repair in mice (Mus musculus). PDGF-BB signals primarily through platelet-derived growth factor receptor-β (PDGFR-β) and PDGFR-α/β receptor complexes, activating intracellular signaling pathways including PI3K/AKT, MAPK, and STAT, which regulate fibroblast activation, smooth muscle cell proliferation, and extracellular matrix production. In mice, PDGF-BB is produced by platelets, macrophages, endothelial cells, fibroblasts, and other stromal cells, and is released during tissue injury, inflammation, and wound healing. Mouse PDGF-BB is widely studied in experimental models of fibrosis, cardiovascular disease, wound healing, and cancer, where PDGF signaling contributes to angiogenesis, mesenchymal cell proliferation, and tissue remodeling. It plays key roles in murine models of atherosclerosis, liver and lung fibrosis, tumor development, and vascular remodeling, helping to regulate interactions between endothelial cells, smooth muscle cells, and fibroblasts. Because mice are the most commonly used genetic model organism in biomedical research, characterization of mouse PDGF-BB has been essential for understanding growth factor–mediated signaling, angiogenesis, and tissue regeneration, providing insights relevant to human vascular disease, fibrosis, and cancer biology.