Natural history of anal human papillomavirus infection in heterosexual women and risks associated with persistence.

BACKGROUND: Anal cancer is more common in women than in men, yet little is known about the natural history of human papillomavirus (HPV) in women. The objective was to examine the natural history of anal HPV in heterosexual women. METHODS: Young women participating in an HPV cohort study were seen at 4-month intervals for cervical and anal HPV testing. Time to clearance was estimated using the Kaplan-Meier approach; risks for persistence were assessed using Cox regression models. RESULTS: Seventy-five women (mean age, 23.5 ± 4.1 years) who tested positive for anal HPV were followed for a mean of 84.5 ± 44.9 months. By 3 years, 82.5% of anal non-16 high-risk (HR) HPV, 82.6% of low-risk (LR) HPV, and 76.2% of HPV-16 infections had cleared. By 3 years, only 36.4% of women had become negative for all HPV types. In the multivariable model, concurrent cervical HPV-16 (P < .001), weekly alcohol use (P = .015), anal touching during sex (P = .045), recent anal sex (P = .04), and no condom use during anal sex (P = .04) were associated with HPV-16 persistence. Greater number of new sex partners (P = .024) and condom use during vaginal sex (P = .003) were associated with clearance. Similar associations were found for clearance in all HR-HPV infections. Only concomitant cervical HPV was associated with non-16 HR-HPV persistence. CONCLUSIONS: The majority of anal HPV infections cleared within 3 years. HPV-16 infections were slower to clear than other HR-HPV infections, consistent with its role in anal cancer. Specific sexual behaviors were associated with persistence, suggesting that education and behavioral interventions may decrease persistence.

Immunohistochemical analysis of the monoclonal antibody 4B5 in breast tissue expressing human epidermal growth factor receptor 4 (HER4).

AIMS: A recent study examining the specificity of human epidermal growth factor receptor (HER) 2 pharmacodiagnostic antibodies demonstrated that CB11 and 4B5 stain both HER2-transfected and HER4-transfected cell lines. However, there has been no evidence showing that 4B5 has affinity for HER4 in clinically obtained tissues, and, if so, whether this has any impact on the assessment of HER2. We therefore sought to determine the expression of membrane-bound HER4 in clinical breast carcinomas, and evaluate its impact on the clinical utility of 4B5 in determining HER2 status. METHODS AND RESULTS: Breast carcinomas were assessed by immunohistochemistry (IHC) for membrane-bound HER4 using anti-HER4 clone E200. HER2 expression in these cases was then assessed using anti-HER2 clone 4B5, and a reference clone, SP3. In all 117 membrane HER4-positive cases (out of 241), 4B5 scored equal to or less than the reference anti-HER2 clone SP3. Eighteen cases were positive for membrane-bound HER4 by E200 and negative by 4B5, including a membrane HER4 level 3+ case. CONCLUSIONS: No cross-reactivity of 4B5 with membrane-bound HER4 was identified in the clinical IHC analysis of formalin-fixed paraffin-embedded breast carcinoma cases as evidenced by the HER4 antibody clone E200.

Inhibition of the transport of HIV in vitro using a pH-responsive synthetic mucin-like polymer system.

In conjunction with the routine role of delivering the active ingredient, carefully designed drug delivery vehicles can also provide ancillary functions that augment the overall efficacy of the system. Inspired by the ability of the cervicovaginal mucus to impede the movement of HIV virions at acidic pH, we have engineered a pH-responsive synthetic polymer that shows improved barrier properties over the naturally occurring cervicovaginal mucus by inhibiting viral transport at both acidic and neutral pH. The pH-responsive synthetic mucin-like polymer is constructed with phenylboronic acid (PBA) and salicylhydroxamic acid (SHA), each individually copolymerized with a 2-hydroxypropyl methacrylamide (pHPMA) polymer backbone. At pH 4.8, the crosslinked polymers form a transient network with a characteristic relaxation time of 0.9 s and elastic modulus of 11 Pa. On addition of semen, the polymers form a densely crosslinked elastic network with a characteristic relaxation time greater than 60 s and elastic modulus of 1800 Pa. Interactions between the PBA-SHA crosslinked polymers and mucin at acidic pH showed a significant increase in elastic modulus and crosslink lifetime (p < 0.05). A transport assay revealed that migration of HIV and cells was significantly impeded by the polymer network at pH ≥ 4.8 with a diffusion coefficient of 1.60 x 10(-4) µm(2)/s for HIV. Additionally, these crosslinked polymers did not induce symptoms of toxicity or irritation in either human vaginal explants or a mouse model. In summary, the pH-responsive crosslinked polymer system reported here holds promise as a class of microbicide delivery vehicle that could inhibit the transport of virions from semen to the target tissue and, thereby, contribute to the overall activity of the microbicide formulation.

Enzymatic triggered release of an HIV-1 entry inhibitor from prostate specific antigen degradable microparticles.

This paper describes the design, construction and characterization of the first anti-HIV drug delivery system that is triggered to release its contents in the presence of human semen. Microgel particles were synthesized with a crosslinker containing a peptide substrate for the seminal serine protease prostate specific antigen (PSA) and were loaded with the HIV-1 entry inhibitor sodium poly(styrene-4-sulfonate) (pSS). The particles were composed of N-2-hydroxyproplymethacrylamide and bis-methacrylamide functionalized peptides based on the PSA substrates GISSFYSSK and GISSQYSSK. Exposure to human seminal plasma (HSP) degraded the microgel network and triggered the release of the entrapped antiviral polymer. Particles with the crosslinker composed of the substrate GISSFYSSK showed 17 times faster degradation in seminal plasma than that of the crosslinker composed of GISSQYSSK. The microgel particles containing 1 mol% GISSFYSSK peptide crosslinker showed complete degradation in 30 h in the presence of HSP at 37°C and pSS released from the microgels within 30 min reached a concentration of 10 µg/mL, equivalent to the published IC(90) for pSS. The released pSS inactivated HIV-1 in the presence of HSP. The solid phase synthesis of the crosslinkers, preparation of the particles by inverse microemulsion polymerization, HSP-triggered release of pSS and inactivation of HIV-1 studies are described.

The role of sexual behavior and human papillomavirus persistence in predicting repeated infections with new human papillomavirus types.

BACKGROUND: Although human papillomavirus (HPV) infections are common in young women, the rate of and risk for repeated new infections are not well documented. We examined the rate of and risks for new HPV detection in young women. METHODS: We used data from an ongoing study of HPV, initiated in 1990. Sexually active women ages 12 to 22 years were eligible. Interviews on behaviors and HPV testing were done at 4-month intervals; sexually transmitted infection (STI) testing was annual or if symptomatic. Starting with first HPV detection, time to the next (second) visit (event) with detection of new HPV types, and then the second event to time to third event was calculated. Risks were determined using Cox proportional hazard model. RESULTS: Sixty-nine percent of 1,125 women had a second event, and of those with a second event, 63% had a third event by 3 years, respectively. Women with HPV persistence from initial visit to second event [hazard ratio (HR) = 4.51 (3.78-5.37)], an STI [HR = 1.47 (1.00-2.17)], bacterial vaginosis [HR = 1.60 (1.07-2.39)], and number of new sex partners [HR = 1.10 (1.05-1.15 per partner/mo)] were independent associations for HPV. Risks for third event were similar. CONCLUSION: This study documents the repeated nature of HPV infections in young women and their association with sexual risk behaviors. IMPACT: This finding underscores the lack of clinical utility of HPV testing in young women. Further studies are needed to examine host factors that lead to HPV acquisition and persistence.

Comparison of natural histories of human papillomavirus detected by clinician- and self-sampling.

New strategies for cervical cancer screening include human papillomavirus (HPV) DNA testing. Using self-testing methods would increase access to testing in both developed and developing countries. The purpose of this study was to compare time-to-clearance of specific HPV types between clinician-collected-lavage (CC-L) and self-collected (SC) sampling in a single cohort. CC-L and SC samples were obtained every 4 months at alternate 2-month windows from 537 women. Eighteen high-risk (HR) HPV and 4 low-risk (LR) HPV were examined. Proportional hazards model was used to compare time-to-clearance between methods for combined HR and for 13 specific HPV types. Prentice-Wilcoxon test was used for within-subject paired comparison. In the independent analysis for combined HR and LR types, no differences were found. For specific types, time-to-clearance for all HPV types examined between CC-L and SC samples was similar except for HPV 66 which showed a trend to clear slower by SC (p = 0.09). When comparing methods in the same woman, time-to-clearance was similar for all types except for HPV 16 which showed a trend to clear slower by CC-L means (p = 0.08). When we examined pattern of clearance among the CC-L samples, the fastest types to clear were HPV 6, 18, 66, 84 and 39 and the slowest were HPV 62, 68, 59 and 16. These patterns of fast and slow were similar for SC samples. Our findings suggest using SC vaginal swabs would observe similar natural histories of HPV compared to studies using CC-L specimens making self-testing feasible for repeated HPV DNA detection.

Multivalent benzoboroxole functionalized polymers as gp120 glycan targeted microbicide entry inhibitors.

Microbicides are women-controlled prophylactics for sexually transmitted infections. The most important class of microbicides target HIV-1 and contain antiviral agents formulated for topical vaginal delivery. Identification of new viral entry inhibitors that target the HIV-1 envelope is important because they can inactivate HIV-1 in the vaginal lumen before virions can come in contact with CD4+ cells in the vaginal mucosa. Carbohydrate binding agents (CBAs) demonstrate the ability to act as entry inhibitors due to their ability to bind to glycans and prevent gp120 binding to CD4+ cells. However, as proteins they present significant challenges in regard to economical production and formulation for resource-poor environments. We have synthesized water-soluble polymer CBAs that contain multiple benzoboroxole moieties. A benzoboroxole-functionalized monomer was synthesized and incorporated into linear oligomers with 2-hydroxypropylmethacrylamide (HPMAm) at different feed ratios using free radical polymerization. The benzoboroxole small molecule analogue demonstrated weak affinity for HIV-1BaL gp120 by SPR; however, the 25 mol % functionalized benzoboroxole oligomer demonstrated a 10-fold decrease in the K(D) for gp120, suggesting an increased avidity for the multivalent polymer construct. High molecular weight polymers functionalized with 25, 50, and 75 mol % benzoboroxole were synthesized and tested for their ability to neutralize HIV-1 entry for two HIV-1 clades and both R5 and X4 coreceptor tropism. All three polymers demonstrated activity against all viral strains tested with EC(50)s that decrease from 15000 nM (1500 microg mL(-1)) for the 25 mol % functionalized polymers to 11 nM (1 microg mL(-1)) for the 75 mol % benzoboroxole-functionalized polymers. These polymers exhibited minimal cytotoxicity after 24 h exposure to a human vaginal cell line.

Factors that influence the rate of epithelial maturation in the cervix in healthy young women.

PURPOSE: To examine the longitudinal changes in the epithelial topography of the cervix in healthy young women; and to determine the sociodemographic, behavioral, and biological factors associated with the rate of cervical epithelial maturation. METHODS: Healthy young women were enrolled from October 2000 to September 2002 as part of a larger study of human papillomavirus (HPV). At interval visits, interviews, infection testing, and colpophotography (3% acetic acid; 10x, 16x magnifications) were performed. Areas of total cervical face and cervical immaturity, defined as columnar and early squamous metaplasia, were quantitatively measured using computerized planimetry. Cervical immaturity was expressed as percentage of total cervical face. This analysis includes the first consecutive 145 women with greater than 10% immaturity at baseline. The rate of cervical maturation was defined as change in percent-immaturity. Predictors included sociodemographics, sexual behaviors, and infections. Data analyses included multivariate generalized linear models with repeated measures. RESULTS: The baseline mean age was 17.8 years. Colpophotographs were available from 815 total visits, representing 2.7 years mean follow-up per woman and 5.9-month mean intervals. Women began the study with a median of 39% immaturity and ended with 8% immaturity. After adjusting for time and baseline percent-immaturity, an increased rate of cervical maturation was associated with oral contraceptive pill use (parameter estimate -.023, p =.04) and smoking (-.039, p =.01). CONCLUSIONS: Cervical maturation was documented during relatively short time periods for the vast majority of these women. Oral contraceptive pills and smoking may accelerate the maturational process, representing increased cell proliferation and thus a possible greater vulnerability to HPV.