Reactivity of two selected antigens of Neisseria gonorrhoeae.

Two antigen preparations, the soluble antigen and a fraction 1 thereof, isolated in the course of a systematic study of the various antigens of the virulent gonococcus, have been investigated for their ability to serve as antigens for the detection of antibody in patients infected with the gonococcus. The soluble antigen was reactive with 88.2% of the sera from infected females, and fraction 1 was reactive with 71.6% of the sera. Of sera from infected males, only 27.6% reacted with the soluble antigen and only 20.4% with fraction 1. Of sera from individuals presumed free of gonococcal infection, approximately 4% reacted with the soluble antigen; none reacted with fraction 1. This study suggests that these antigens might be adaptable to the detection of human gonococcal antibody, especially in the female.

Isolation of an antigen of Neisseria gonorrhoeae involved in the human immune response to gonococcal infection.

Ion-exchange chromatography was used to isolate a fraction from disrupted gonococci which reacts with sera from patients with gonococcal disease in complement-fixation and gel-diffusion tests. This antigenic fraction was shown to be the same as that previously described as having been isolated by gel filtration. The method reported here has the advantage of greater rapidity of isolation together with some improvement in purity.

Antigens of Neisseria gonorrhoeae: characterization by gel filtration, complement fixation, and agar-gel diffusion of antigens of gonococcal protoplasm.

With the use of the agar-gel-diffusion and complement-fixation techniques, it was shown that protoplasm from different gonococcal isolates reacted with sera from some humans with a history of gonorrhea but did not react with "normal" human sera. The reactive antigen(s) could be partially separated from the other antigens by passing the gonococcal protoplasm through Sephadex G-200. The antigen(s) reacting in the gel-diffusion and complement-fixation tests appeared in the same fraction. On the basis of Sephadex gel filtration, the molecular weight of this antigen(s) is probably greater than 200,000.