Used in immunological research to detect and quantify rat CD90 (Thy-1) antigen levels in biological samples such as serum, plasma, and cell culture supernatants. Commonly applied in studies involving T-cell activation, stem cell characterization, and neural development due to CD90's expression on the surface of various cell types including thymocytes, neurons, and some mesenchymal stem cells. The ELISA format allows for high-throughput, sensitive, and specific measurement, making it valuable in both basic research and preclinical studies focused on immune response, tissue regeneration, and cancer biology.