Production and characterization of monoclonal antibodies against the ribosome-inactivating protein PAP from Phytolacca americana.

Monoclonal antibodies specific to pokeweed antiviral protein (PAP), a ribosome-inactivating protein (RIP), were obtained after six unsuccessful fusions. A special procedure including injections of low doses of purified PAP from spring leaves in a short period was adopted. Some clones highly specific to PAP react with recombinant PAP. One clone cross-reacts with PAP-S isolated from seeds but none cross-reacts with the isoform PAP II isolated from summer leaves. These antibodies represent a useful tool to investigate the mechanisms of PAP biosynthesis and plant protection involving RIPs.