A Microtest Radioimmunoassay for Noncytotoxic Tumor-Specific Antibody to Cell-Surface Antigens2

Abstract

A radioimmunoassay capable of measuring cytolytic and noncytolytic antibodies directed against cell-surface antigens was developed. Cells of the murine lymphoma L-5178Y grown in culture were used as a solid-phase immunoadsorbent to which the antibodies in the sera were bound. These bound antibodies were then detected by reacting the treated cells with a purified ¹²⁵I-labeled, anti-mouse- Fab antibody. Specific antibody was found in a serum from DBA/2J mice (syngeneic host) hyperimmunized against the L-5178Y tumor. This serum was not cytolytic in a complement-dependent assay.