[Quantitative immunoenzyme method of analyzing embryonal prealbumin (EPA-1) in biological fluids].

A quantitative immunoenzymatic method (ELISA) has been developed for detection of embryonic prealbumin (EPA-1). This method allows EPA-1 to be detected in human serum in an amount of 4 to 100 ng/ml. The high levels of EPA-1 (over 4 ng/ml) were observed in all cases (27 patients) of tumors of connective tissues, in 50 of 51 in brain tumors, in 39 of 341 in gastrointestinal tract tumors, in 4 of 13 in breast tumors, and in 21 of 51 tumors of the respiratory tract. The levels of EPA-1 in donors and pregnant woman sera normally did not exceed 4 ng/ml. However, about 3% of the samples of these sera had the levels of EPA-1 from 4 to 12 ng/ml.