1. Immunohistological fication by micromethods such as API localization of carcinoembryonic antigen (20E) is unsatisfactory owing to their and nonspecific cross-reacting antigen in gastrointestinal normal and tumoral tissues;King, M.;Cancer Research,1973
2. Nonspecific cross-reacting antigen as a marker for human polymorphs, macrophages and monocytes;Burtin, P.; Quan, P.C.; Sabine, M.C.;Nature; general lack of biochemical activity. (The absence of a pathogenic role makes it undesirable to use the more sophisticated tests such as cell wall composition, as routine tests show that the only regular difference is the oxidase reaction.) About,1975