In addition, to the extent that Gc reside intracellularly and thereby escape antibody-mediated defenses, T cell-mediated immunity could have a role that merits exploration. Repeat exposure and bactericidal

antibodies were associated with reduced risk of salpingitis [35], however there are few data to support a protective immune response against uncomplicated infections. In one report, repeatedly infected women in Nairobi, Kenya showed partial serovar-specific immunity against the prevalent Z-VAD-FMK ic50 circulating Gc strain [45], this finding was not replicated in a study of less exposed subjects in a rural setting in the United States [46]. Antibodies against the reduction-modifiable protein (Rmp) block the bactericidal activity of PorB or LOS-specific antibodies, and the relative proportion of blocking and bactericidal antibodies has been proposed to correlate with immunity [47]. Lacking are studies on the effect of high-titer bactericidal antibody, which natural infection does not induce, or cellular immunity in protecting against

human infection. Erastin The conventional paradigm in vaccine development of mimicking natural infection to provoke an immune response without actually causing disease, therefore, is not applicable to gonorrhea as recovery does not confer protective immunity against re-infection. This situation could arise either because a specific immune response is ineffective against a continually variable antigenic target like Gc, or because Gc interferes with the normal course mafosfamide of an immune response and suppresses its development. A successful vaccine must demonstrate the ability to protect against all or most known and unknown antigenic types, and novel approaches to address this challenge are needed. In addition, if the mechanisms by which Gc manipulates the host immune responses

can be identified, vaccines might be designed to inhibit or sidestep these mechanisms and allow an effective protective immune response to develop. The relative contributions of Th17-driven innate responses and Th1/Th2-driven adaptive responses to protective immunity remain to be elucidated. Gc-induced immunosuppression in mice can be reversed by treatment with blocking antibodies against TGF-β and IL-10, which permit the development of Th1- and Th2-dependent responses with circulating and vaginal anti-Gc antibodies, immunological memory, and protective immunity against reinfection (48) (Liu Muc Immun 2013, in press). However, neutralization of TGF-β also inteferes with Th17 responses (48).