About this Research Topic
Immunity to N. gonorrhoeae is a topic that until recently has been hard to define, because there is currently no clearly established state of immunity to gonorrhea in humans, which are the only natural host for this infection. Furthermore, until recently, only one animal model of genital tract infection has been developed, known as the estradiol-treated female mouse model. However, N. gonorrhoeae is eliminated within ~2 weeks in this species. Similar to humans however, recovery does not lead to immune resistance to re-infection. It has generally been thought that the extraordinary capacity for N. gonorrhoeae to vary the expression and epitope structure of most of its major surface antigens, coupled with multiple mechanisms for evading complement activation and its consequences, enable the gonococcus to obviate host immune defenses.
However recent findings have begun to cast new light on this problem. Among these are the demonstration that N. gonorrhoeae (i) suppresses the development of Th1- and Th2-driven adaptive immune responses, while (ii) eliciting Th17-driven innate defenses (such as anti-microbial proteins and phagocytes) that it appears to be capable of surviving. In addition, conserved, stably-expressed antigens derived from N. gonorrhoeae have been identified, implying that protective vaccines may be feasible. However, the mechanisms involved in protective immunity to N. gonorrhoeae remain to be determined. Mechanisms of complement evasion and resistance to phagocytic killing continue to be elucidated. Strategies for reversing the apparent immunosuppression have been devised that offer the prospect of new approaches to therapy and vaccine development. A recent report demonstrating that subjects immunized with a meningococcal outer membrane protein vaccine have reduced risk of gonococcal infection, provides an enticing suggestion that a state of immunity can be induced in humans. However, further studies are needed in order to investigate the mechanisms responsible for this finding.
This Research Topic will bring together these developments, provide a comprehensive view of the current state of knowledge, and prioritize the critical questions that remain to be answered in relation to our understanding of immunity to N. gonorrhoeae. We aim to discuss issues that impact on vaccine development, including understanding immune evasion and immune pathogenesis and general strategies for target selection (e.g. proteomics and nutritional immunity). In turn, this will stimulate further research in directions that should facilitate the discovery of new approaches to therapy and vaccine development, which are becoming of critical importance with the continuing emergence of resistance to currently available antibiotics.
We welcome the submission of Review, Mini-Review, Opinion and Original Research articles that encompass, but are not limited to, the following topics:
1. Human immune response to N. gonorrhoeae (innate and adaptive).
2. Correlates or determinants of protection against N. gonorrhoeae.
3. Mechanisms of immune manipulation by N. gonorrhoeae.
4. Mechanisms of immune resistance by N. gonorrhoeae.
5. Mechanisms of immune defense against N. gonorrhoeae.
6. Nutritional immunity to N. gonorrhoeae.
7. Novel gonococcal vaccines, adjuvants, delivery strategies.
8. Strategies of antigen identification; impact on vaccine development.
9. New models of gonococcal infection and immunity.
10. Relevant lessons from other organisms, e.g., N. meningitidis.
11. Epidemiological studies on potential impact of a gonococcal vaccine.
12. Regulatory and societal issues in gonococcal vaccine deployment.
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.