Method for the detection and identification of alpha fetoprotein in serum.

The value of the demonstration of alpha, feto-protein (a, FP) in the diagnosis of hepatoma is now well established' (O'Connor, Tatarinov, Abeleve, and Uriel, 1970; Purves, Bersohn, and Geddes, 1970). The technique most commonly used for this purpose is bidimensional immuno-diffusion which is simple and practical, but may take up to 72 hours and is not very sensitive. The complement-fixation test and radial immuno-diffusion have also been used. The former is more sensitive but it is rather difficult to establish its specificity whereas the latter requires relatively large quantities of antiserum. Radio-immuno-assay involves isotope labelling. This paper describes a technique for the detection and identification of a, FP in serum by means of counter-current (cross-over) electrophoresis in agar gel (Bussard, 1959; Culliford, 1964, Kohn, 1967). The specificity of the precipitation lines is established by a reaction of identity with a positive control incorporated in the test system. Electrophoresis is performed on agar gel with the antigen sample on the cathode and the antibody on the anode. Under these conditions the reactants are propelled towards each other. The speed and sensitivity of the test greatly increases. Agar