Used in immunological research to quantify rat macrophage colony-stimulating factor (M-CSF) levels in biological samples such as serum, plasma, and cell culture supernatants. Enables researchers to study the role of M-CSF in immune regulation, inflammation, macrophage differentiation, and host defense mechanisms. Commonly applied in studies related to autoimmune diseases, infectious diseases, cancer, and bone metabolism where M-CSF signaling is involved. Provides a sensitive and specific method for monitoring changes in M-CSF expression under experimental conditions.