[Biosynthesis and cellular localization of embryonal prealbumin in human embryonal tissues].

Immunofluorescent analysis of chorion sections and various embryonal tissues revealed localization of embryonal prealbumin (EPA) in the mesenchymal cells of the chorion, bones, umbilical cord, skin and in the cytoplasm of the epithelium distal part of the embryonal kidney canals. Synthesis of EPA slow peak in the suspension tissue culture of the chorion, umbilical cord and bones was shown. It is suggested that EPA is a mesenchyme product which is actively synthesized during the period of embryonal development. EPA is resynthesized and localized in the cells of tumors originated from the connective tissue. Cells of the tumors of non-connective origin did not contain EPA, whereas it was detected in the cells of the adjacent connective tissue. The phenomenon of embryonal reversion, probably, takes place not only in the "original" tumor cells but also in the surrounding connective tissues.