The Journal of Medical Microbiology, Vol 12, Issue 3 283-289, Copyright © 1979 by Society for General Microbiology
Protection by monospecific gonococcal antisera of the chicken embryo challenged with Neisseria gonorrhoeae
J. N. Robertson
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. Antiserum raised against whole
outer membrane was protective and antiserum raised against the
lipopolysaccharide (LPS) was moderately protective. Outer-membrane
antiserum from which the LPS component was removed by absorption was less
protective than either of these sera. Investigation of the protective
mechanism of anti-LPS antibodies indicated that in addition to any
antitoxic effect, these antibodies inhibited the multiplication of
gonococci. Antisera raised against individual outer-membrane proteins
offered no protection in this test. Out of five antisera tested, antipilus
serum gave the strongest protection when piliate gonococci were used as the
challenge in this model; antipilus serum did not protect against challenge
with non-piliate gonococci.
