Three gel formulations (1%, 3%, and 5% [wt/wt]) of SPL7013, a dendrimer known to have antiviral (anti-human immunodeficiency virus and anti-herpes simplex virus) activities, completed a range of preclinical tests in the pigtailed macaque models for vaginally and rectally applied topical microbicide safety assessments. The vaginal safety profile of the 3% SPL7013 gel formulation was equal to that of the 1% formulation but was superior to that of the 5% formulation. The 3% SPL7013 gel was further evaluated for rectal safety and for antichlamydial efficacy with cervical challenge with Chlamydia trachomatis. This first-generation dendrimerbased product was shown to be safe to the vaginal and rectal microenvironments with repeated daily use. However, a single intravaginal application of the 3% (wt/wt) SPL7013 gel did not provide protection from the acquisition of cervical chlamydial infection.The use of topical microbicides is an emerging strategy for the prevention of transmission of human immunodeficiency virus (HIV) and other sexually transmitted infections. Topical microbicide products should optimally be safe and effective for repeated vaginal and/or rectal use.Dendrimers are a novel class of macromolecules characterized by highly branched three-dimensional structures (15). Dendrimers have good antiviral activities against both HIV and herpesvirus and physical properties appropriate for microbicide applications (2,3,5,(7)(8)(9)17). SPL7013, a dendrimerbased microbicide developed by Starpharma Pty Ltd., Melbourne, Australia, has emerged as a candidate for such a product (10,15).In this study, three gel formulations (1%, 3%, and 5% [wt/ wt]) of SPL7013 were assessed in a range of preclinical safety tests performed with the established pigtailed macaque models of repeated vaginal and rectal application (11-13). The vaginal safety profile of the 3% SPL7013 gel formulation was equal to that of the 1% formulation but was superior to that of the 5% formulation. Unformulated SPL7013 has been shown in separate mouse models to protect against genital herpes simplex virus type 2 infection and significantly reduce the incidence of ascending genital tract infection caused by Chlamydia trachomatis (2, 3). Thus, the 3% SPL7013 gel formulation was further evaluated for rectal safety and antichlamydial efficacy with a cervical challenge of C. trachomatis. MATERIALS AND METHODSTest products. Dendrimer gel formulations containing 1%, 3%, and 5% (wt/ wt) SPL7013 and a placebo gel were provided by Starpharma Pty Ltd.Animals. Sexually mature, female Macaca nemestrina macaques were obtained from a colony of animals at the Washington National Primate Research Center. Prior approval for use of the monkeys in this protocol was obtained from the Institutional Animal Care and Use Committee at the University of Washington. The animals were handled humanely, and experiments were performed within the National Institutes of Health's animal use guidelines. Experimental safety protocols. (i) Vaginal safety.Three concentrations of SPL7013 in a wa...

The role of delayed hypersensitivity in the pathogenesis of Chlamydia t trachomatis salpingitis was studied in the monkey "pocket" model. Pigtailed monkeys (Macaca nemestrina) were sensitized by inoculation of live C. trachomatis organisms (E/UW-5/Cx) into subcutaneous pockets containing salpingeal autotransplants. At 21 days, affinity-purified recombinant C. trachomatis heat-shock protein (rhsp60) was injected into pockets either previously sensitized with C. trachomatis or not sensitized in the same monkey. Delayed-type hypersensitivity reaction was observed, characterized by mononuclear cell infiltration with peak reaction at 48 h. Injection of rhsp60 into the pockets of a naive animal did not induce inflammation. This study showed that C. trachomatis infection in monkeys induced delayed hypersensitivity, which is mediated by hsp60. Histologic findings of the salpinx were consistent with delayed hypersensitivity reaction observed in ocular C. trachomatis infection, further suggesting a similar pathogenesis for both salpingitis and trachoma.

Mycoplasma genitalium is a sexually transmitted pathogen associated with several acute and chronic reproductive tract disease syndromes in men and women. To evaluate the suitability of a pig-tailed macaque model of M. genitalium infection, we inoculated a pilot animal with M. genitalium strain G37 in the uterine cervix and in salpingeal pockets generated by transplanting autologous Fallopian tube tissue subcutaneously. Viable organisms were recovered throughout the 8-week experiment in cervicovaginal specimens and up to 2 weeks postinfection in salpingeal pockets. Humoral and cervicovaginal antibodies reacting to MgpB were induced postinoculation and persisted throughout the infection. The immunodominance of the MgpB adhesin and the accumulation of mgpB sequence diversity previously observed in persistent human infections prompted us to evaluate sequence variation in this animal model. We found that after 8 weeks of infection, sequences within mgpB variable region B were replaced by novel sequences generated by reciprocal recombination with an archived variant sequence located elsewhere on the chromosome. In contrast, mgpB region B of the same inoculum propagated for 8 weeks in vitro remained unchanged. Notably, serum IgG reacted strongly with a recombinant protein spanning MgpB region B of the inoculum, while reactivity to a recombinant protein representing the week 8 variant was reduced, suggesting that antibodies were involved in the clearance of bacteria expressing the original infecting sequence. Together these results suggest that the pig-tailed macaque is a suitable model to study M. genitalium pathogenesis, antibody-mediated selection of antigenic variants in vivo, and immune escape. Mycoplasma genitalium is a recently recognized sexually transmitted pathogen associated with reproductive tract disease in men and women (reviewed in references 1 to 3). Infection with this organism has been associated with urethritis in men (4-6) and cervicitis (7-9), urethritis (10, 11), acute endometritis (12), chronic pelvic inflammatory disease (13), tubal factor infertility (14, 15), and preterm birth (16, 17) in women. When untreated or inappropriately treated, M. genitalium infection can persist for months to years (18-21), suggesting that this organism avoids elimination by the host immune response. Recent studies assessing M. genitalium treatment regimens have found that standard antibiotic therapy fails to cure a significant proportion of infections (reviewed in reference 1), highlighting the importance of a better understanding of M. genitalium pathogenesis so that effective treatment and prevention methods can be devised.The distinct flask-shaped morphology of M. genitalium cells can be attributed to its complex tip organelle involved in gliding motility (22-25) and adherence to host cells and inanimate surfaces (26-30). Included among the tip organelle-associated proteins are the major adhesin, MgpB (also known as MgPa or P140), and its accessory protein, MgpC (also known as P110), which is required for the sta...

OCT is a noninvasive imaging modality complementary to colposcopy. It distinguished between normal and abnormal (or injured) tissue and thus holds promise for safety evaluations of candidate microbicides and other vaginal products.

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