Abstract
The protective effects of monospecific gonococcal antisera on 11-day chick embryos challenged with a known lethal dose of gonococci were assessed. The monospecific antisera were prepared by immunisation of rabbits with purified gonococcal antigens, and removal of trace amounts of unwanted antibodies was achieved by absorption with antigen covalently bound to cyanogen bromide-activated Sepharose beads. The antisera were standardised for IgG by solid-phase radioimmunoassay.