Rat CXCL9 (C-X-C motif chemokine ligand 9), also known as MIG (monokine induced by interferon-γ), is a proinflammatory chemokine belonging to the CXC chemokine family, which also includes CXCL10 (IP-10) and CXCL11 (I-TAC) that regulate T-cell recruitment during interferon-driven immune responses. In rats (Rattus norvegicus), CXCL9 is produced by macrophages, dendritic cells, endothelial cells, epithelial cells, and fibroblasts in response to interferon-γ (IFN-γ) and inflammatory stimuli during infection or immune activation. CXCL9 signals primarily through the chemokine receptor CXCR3, expressed on activated T lymphocytes, natural killer (NK) cells, and other immune cells, promoting chemotaxis and accumulation of these cells at sites of infection or inflammation. In rat biology, CXCL9 contributes to Th1-type cell-mediated immune responses against intracellular pathogens and plays an important role in inflammatory processes affecting tissues such as the lung, liver, and central nervous system. Rat models have been widely used to study autoimmune and inflammatory diseases, including experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis, where CXCL9 participates in the CXCR3-mediated recruitment of T cells into the central nervous system, contributing to neuroinflammation and demyelinating pathology.