Abstract: A kit for assaying the activation of terminal complement cascade is disclosed. The kit includes a plurality of containers which contain a first antibody having a specificity for poly C9 neoantigen. The containers further have a second antibody which is different from the first antibody and has a specificity for a constituent of terminal complement cascade. A third antibody is optionally present which recognizes the second antibody. The kit also includes a substrate splitting enzyme, a substrate for the enzyme which produces a color reaction when split, and a SCb-9 standard microtiter plate. Pipettes and instructions for performing the assay are also included.

Abstract: The present invention discloses an enzyme-linked immunosorbent assay (ELISA) to quantitate fluid phase terminal complement activation. Upon activation to form C5b-9, terminal complement components express neoantigens not present in the unassembled individual components. Rabbit antiserum to polymerized C9 was rendered specific for C9 neoantigenic determinants by serial immunosorbtion with human serum, human C9, and other terminal complement components bound to Sepharose. Using the IgG from this antiserum, a sandwich ELISA was devised to bind SC5b-9 from solution onto polystyrene plates. The ELISA plates were developed with the use of goat antiserum to native C9 epitopes followed by a swine anti-goat IgG alkaline phosphatase conjugate. Quantitation of SC5b-9 in solution was performed by comparing sample OD to a standard curve generated with human SC5b-9 that was purified from zymosan-activated serum.