The quantikine fish major histocompatibility complex (MHC) immunoassay is a 4.5 hour solid phase elisa designed to measure major histocompatibility complex (MHC) levels in cell culture supernates, serum, and plasma. It contains e. Coli-expressed recombinant fish major histocompatibility complex (MHC) and antibodies raised against recombinant fish major histocompatibility complex (MHC). This immunoassay has been shown to accurately quantitate the recombinant factor. Results obtained using natural fish major histocompatibility complex (MHC) showed dose response curves that were parallel to the standard curves obtained using the recombinant quantikine kit standards. These results indicate that this kit can be used to determine relative mass values for natural fish major histocompatibility complex (MHC)