Experimental Human Gonococcal Urethritis: 250 Neisseria gonorrhoeae MS11mkC Are Infective

• Published in: The Journal of infectious diseases Vol. 172; no. 1; pp. 180 - 185
• Main Authors: Schneider, Herman, Cross, Alan S., Kuschner, Robert A., Taylor, David N., Sadoff, Jerald C., Boslego, John W., Deal, Carolyn D.
• Format: Journal Article
• Language: English
• Published: Chicago, IL The University of Chicago Press 01.07.1995; University of Chicago Press
• Subjects: Adolescent; Adult; Antibodies, Monoclonal; Antigens, Bacterial - biosynthesis; Bacterial diseases; Biological and medical sciences; Dysuria; Genetic Variation; Gonorrhea; Gonorrhea - microbiology; Gonorrhea - urine; Human bacterial diseases; Humans; Infections; Infectious diseases; Inoculation; Inoculum; Lipopolysaccharides - biosynthesis; Major Articles; Male; Medical sciences; Middle Aged; Miscellaneous; Neisseria gonorrhoeae; Neisseria gonorrhoeae - genetics; Neisseria gonorrhoeae - isolation & purification; Neisseria gonorrhoeae - pathogenicity; Phenotype; Phenotypes; Sediments; Urethritis; Urethritis - microbiology; Urethritis - urine; Volunteerism; Human; Urinary system disease; Urethral disease; Neisseriaceae; Urine culture; Urinary tract disease; Infection; Experimental disease; Gonococcal infection; Microbiological investigation; Neisseria gonorrhoeae; Bacteriosis; Bacteria; Micrococcales; Urethritis
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1093/infdis/172.1.180

Neisseria gonorrhoeae MS11mkA (mkA) expressesone 3.6-kDa lipooligosaccharide (LOS). Variant MS11mkC (mkC), expressing four larger LOSs, occurs in vitro among mkA at a frequency of 10−3. Infectivity of these variants was compared in 2 groups of volunteers inoculated with ∼40,000 piliated, Opa− gonococci of either strain. The mkC variant infected 5 of 5 while mkA infected only 2 (40%) of 5. Gonococci recovered from the mkA infections showed a transition toward the mkC LOS phenotype. The mkA inoculum contained ∼40 mkC gonococci. These data confirmed earlier studies and suggested that small numbers of mkC gonococci would be infective. This hypothesis was tested in three more experiments. In two, volunteers were inoculated with 250 or 1250 mkC, infecting 3 of 7 in each group, and in the third, 1600 mkC infected 2 of 6, resulting in a total of 8 of 20 infected by ⩾ 1600 mkC. Gonococci shed by infected volunteers maintained the mkC LOS phenotype but shifted from Opa− to Opa+. Thus, LOS and opacity protein, as well as pilus, are gonococcal virulence factors.