Preparation of cell walls and protoplasm of Neisseria with the Ribi cell fractionator

Particulate Fractions of Neisseria gonorrhoeae

Passage of gonococcal cells through a Ribi cell fractionator produced a mixture of protoplasm and cell particulates, the latter being separable in sucrose solutions. Separation of these particulates resulted in the detection of objects identified as cell walls and "plasts." The latter objects had an average diameter of 1.00 +/- 0.05 mum and consisted of spatially oriented granules surrounded by a membrane-like structure only. Cell wall structures were not observed with these plasts. Plasts were morphologically stable in distilled water and at low pH values. Although 50% more pressure was required to rupture plasts than whole cells, plast morphology was destroyed by organic solvents. Whole cell and plast morphology was examined by electron and phase microscopy, and certain correlations were made between structure and morphological stability. Cell wall antiserum reactivities were quantitatively different for plasts and cell walls. Serological reactivities of plasts were separable by sonic oscillation and differential centrifugation of the sonically treated material.

Lymphocyte transformation in repeated gonococcal urethritis

In an attempt to ascertain whether cell-mediated hypersensitivity develops in the course of a naturally acquired gonorrhea infection, lymphocytes from men with gonococcal urethritis were cultured in vitro with a gonococcal antigen. The lymphocyte response was quantitated by a radioactive assay of deoxyribonucleic acid synthesis. Lymphocytes from subjects without gonorrhea were cultured in a similar manner to determine the specificity of the reaction. The recurrent nature of many gonococcal infections allowed a concurrent evaluation of whether the intensity of the in vitro lymphocyte response is related to the history of previous exposure to the antigen concerned. This study revealed a significantly greater lymphocyte response to the gonococcal antigen in those with gonorrhea infections than in the nongonorrhea subjects (P < 0.01). The intensity and timing of the response were also consistent with specific lymphocyte stimulation.

Chemical characterization of organisms isolated from leprosy patients

CHEMICAL ANALYSES OF THE CELL WALLS OF ORGANISMS ISOLATED IN VARIOUS PARTS OF THE WORLD FROM CASES OF LEPROMATOUS AND TUBERCULOID LEPROSY MAKE POSSIBLE THEIR ASSIGNMENT TO ONE OF THE THREE GENERA: Corynebacterium, Mycobacterium, or Propionibacterium. One, bacterium 22M, remains unassigned. The combined chemical and enzymatic properties attributed to leprosy bacilli freshly harvested from lepromata are found collectively, but not individually, in these three genera.

Human antibody response to lipopolysaccharides from Neisseria gonorrhoeae

Red cells coated with lipopolysaccharides from three different strains of Neisseria gonorhoeae have been used as antigens in a haemagglutination test for gonococcal antibodies. For each strain the geometric mean titre in sera from 50 male and 25 female patients was significantly higher than that in 50 normal controls. The most useful smooth strain, G1, picked out 84% of females and 46% of males from a group of patients known to have gonorrhoea, but only gave 2% positives among controls. The rough strain, G2, gave 10% positives in controls and 31% in patients. The results suggest that the method is worth developing further as a diagnostic test and that strain differences are important. False positives were probably due to cross-reacting antibodies.

An automated complement fixation procedure for detecting antibody to N. gonorrhoeae

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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.