Published in Volume
70, Issue 1
(July 1, 1982)J Clin Invest.
1982, The American Society for
Characterization of Serum Resistance of Neisseria gonorrhoeae that Disseminate: ROLES OF BLOCKING ANTIBODY AND GONOCOCCAL OUTER MEMBRANE PROTEINS
The Maxwell Finland Laboratory for Infectious Diseases, Boston City Hospital, Boston University School of Medicine, Boston, Massachusetts 02118
Channing Laboratory, Beth Israel Hospital, Harvard Medical School, Boston, Massachusetts 02115
Published July 1, 1982
Neisseria gonorrhoeae isolated from patients with disseminated infection (DGI) often resist complement (C′)-dependent killing by normal human serum (NHS) and less commonly by convalescent DGI serum. 7 of 10 NHS specimens completely inhibited killing of serum-resistant (serr) gonococci by convalescent or immune DGI serum. Immunoglobulin G (IgG) purified from NHS was shown to be the blocking agent. In addition, IgM (plus C′) purified from NHS was shown to be fivefold more effective (wt/wt) in killing serum-sensitive (sers) gonococci than equivalent amounts of IgM tested in the presence of IgG (whole serum). Although inhibition of NHS killing of sers gonococci required a 640% excess of IgG, only a 40% excess was required to block immune serum killing of serr gonococci. F(ab′)2 prepared from IgG also blocked killing of serr gonococci by immune serum indicating antigenic specificity of blocking IgG.
IgG immunoconcentrated against outer membrane protein (OMP) derived from serr gonococci showed 40-fold increased blocking activity over normal IgG (wt/wt) and lacked antibody activity directed against gonococcal lipopolysaccharide by ELISA. Using direct immunoabsorption of IgG with purified gonococcal OMP; serr-OMP was found sixfold more effective than sers-OMP in neutralizing the blocking of immune serum killing of serr gonococci, and 10-fold more effective in systems that used excess blocking IgG, NHS, and sers gonococci. Blocking IgG preabsorbed with whole serr gonococci lost 75% of its ability to block immune serum killing compared with no loss in this system using a similar absorption with sers gonococci. IgG purified from NHS contained fivefold higher titers of antibody against serr-OMP than sers-OMP by ELISA.
Click on an image below to see the page. View
PDF of the complete article