Detection of CgA and CgA fragments by 76, 78, 439, 436/439, and 436/439+FRs-ELISAs in plasma samples obtained from healthy subjects. (A-D) Binding curves of recombinant CgA and CgA fragments obtained by 76, 78, 439, and 436/439+FRs-ELISA. Insets: schematic representation of the assays. (E) Circulating levels of natural CgA and CgA fragments, as measured with the indicated assays in plasma samples obtained from 6 healthy human subjects.