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Expression of outer membrane protein II by gonococci in experimental gonorrhea
1Laboratory of Microbial Structure and Function, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840.
Abstract:
Gonorrheal urethritis was induced in three males by intraurethral instillation of predominantly pilus+ protein II- gonococci. Virtually all gonococci reisolated from the infected men exhibited protein II+ phenotype. The reisolated gonococci expressed five distinct outer membrane protein II species. Protein IIc+ organisms predominated in urines of all three subjects, but variants expressing this particular protein II were rarely spawned in vitro by input organisms. Protein IIc+ gonococci appeared early in one man's infection; they were joined later by variants that displayed eight other protein II phenotypes, including protein II-. These results show that input protein II- gonococci are supplanted by protein IIc+ variants during incipient gonorrheal urethritis. As infection progresses, a broader variety of protein II+ variants appears.
Insights
Infections with Neisseria gonorrhoeae (gonococci) rapidly shift from protein II- to protein II+ variants. Protein IIc+ gonococci dominate early infections, with more variants appearing as the infection progresses.
Area of Science:
- Microbiology
- Infectious Diseases
- Bacteriology
Background:
- Neisseria gonorrhoeae causes gonorrheal urethritis.
- Outer membrane protein II (PII) expression varies among gonococcal strains.
- PII variants may play a role in gonococcal pathogenesis and immune evasion.
Purpose of the Study:
- To investigate the in vivo expression and evolution of gonococcal outer membrane protein II (PII) during urethritis.
- To determine if specific PII phenotypes are selected during infection.
Main Methods:
- Induction of gonorrheal urethritis in three male subjects via intraurethral inoculation of predominantly PII- gonococci.
- Isolation and phenotypic characterization of gonococci from patient urines throughout the infection course.
- Analysis of PII species expressed by reisolated gonococci.
Main Results:
- Reisolated gonococci predominantly exhibited a PII+ phenotype, differing from the input PII- strain.
- Five distinct PII species were identified in reisolated organisms.
- Protein IIc+ variants predominated in all subjects' urines early in infection.
- As infection progressed, a wider array of PII+ variants, including PII-, emerged.
Conclusions:
- Gonorrheal urethritis involves a rapid shift from PII- to PII+ gonococcal variants in vivo.
- Protein IIc+ variants are strongly selected during the early stages of infection.
- The emergence of diverse PII phenotypes suggests adaptation and immune evasion strategies by Neisseria gonorrhoeae during infection.