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1.
mBio ; 6(5): e00221-15, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-26330510

ABSTRACT

UNLABELLED: Particular types of hormonal contraceptives (HCs) and genital tract infections have been independently associated with risk of HIV-1 acquisition. We examined whether immunity in women using injectable depot medroxyprogesterone acetate (DMPA), combined oral contraceptives (COC), or no HCs differs by the presence of cervicovaginal infections. Immune mediators were quantified in cervical swabs from 832 HIV-uninfected reproductive-age Ugandans and Zimbabweans. Bacterial infections and HIV were diagnosed by PCR, genital herpes serostatus by enzyme-linked immunosorbent assay (ELISA), altered microflora by Nugent score, and Trichomonas vaginalis and Candida albicans infection by wet mount. Generalized linear models utilizing Box-Cox-Power transformation examined associations between levels of mediators, infection status, and HCs. In no-HC users, T. vaginalis was associated with broadest spectrum of aberrant immunity (higher interleukin 1ß [IL-1ß], IL-8, macrophage inflammatory protein 3α [MIP-3α], ß-defensin 2 [BD2], and IL-1 receptor antigen [IL-1RA]). In women with a normal Nugent score and no genital infection, compared to the no-HC group, COC users showed higher levels of IL-1ß, IL-6, IL-8, and IL-1RA, while DMPA users showed higher levels of RANTES and lower levels of BD2, both associated with HIV seroconversion. These effects of COC were blunted in the presence of gonorrhea, chlamydia, trichomoniasis, candidiasis, and an abnormal Nugent score; however, RANTES was increased among COC users with herpes, chlamydia, and abnormal Nugent scores. The effect of DMPA was exacerbated by lower levels of IL-1RA in gonorrhea, chlamydia, or herpes, SLPI in gonorrhea, and IL-1ß, MIP-3α, and IL-1RA/IL1ß ratio in trichomoniasis. Thus, the effects of HC on cervical immunity depend on the genital tract microenvironment, and a weakened mucosal barrier against HIV may be a combined resultant of genital tract infections and HC use. IMPORTANCE: In this article, we show that in young reproductive-age women most vulnerable to HIV, hormonal contraceptives are associated with altered cervical immunity in a manner dependent on the presence of genital tract infections. Through altered immunity, hormones may predispose women to bacterial and viral pathogens; conversely, a preexisting specific infection or disturbed vaginal microbiota may suppress the immune activation by levonorgestrel or exacerbate the suppressed immunity by DMPA, thus increasing HIV risk by their cumulative action. Clinical studies assessing the effects of contraception on HIV susceptibility and mucosal immunity may generate disparate results in populations that differ by microbiota background or prevalence of undiagnosed genital tract infections. A high prevalence of asymptomatic infections among HC users that remain undiagnosed and untreated raises even more concerns in light of their combined effects on biomarkers of HIV risk. The molecular mechanisms of the vaginal microbiome's simultaneous interactions with hormones and HIV remain to be elucidated.


Subject(s)
Contraceptives, Oral, Hormonal/adverse effects , Immunologic Factors/adverse effects , Immunomodulation , Medroxyprogesterone/adverse effects , Reproductive Tract Infections/immunology , Adolescent , Adult , Contraceptives, Oral, Hormonal/administration & dosage , Disease Susceptibility , HIV Infections/transmission , Humans , Immunologic Factors/administration & dosage , Medroxyprogesterone/administration & dosage , Uganda , Young Adult , Zimbabwe
2.
New Microbiol ; 38(2): 267-70, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25938752

ABSTRACT

An enzymatic assay was developed to determine the concentration of diamines (DA) in clinical samples of vaginal fluids. Putrescine and cadaverine are DA produced by anaerobic bacteria and are typically present in the vaginal fluids of women with an abnormal microbiota, as occurs in bacterial vaginosis. The vaginal DA (VADA) assay is based on the enzyme diamine oxidase which reacts with putrescine and cadaverine to produce H2O2 in a quantitative manner. H2O2 concentration is measured spectrophotometrically by a chromogenic reaction catalyzed by horseradish peroxidase. The VADA assay proved to be capable of detecting DA concentrations as low as 4 mM and showed a dose-response relationship which was linear over DA concentrations ranging from 4 to 256 mM. Using clinical samples it was possible to show that the VADA assay can be performed on human vaginal swabs and that the mean DA concentration is significantly higher in samples positive for microbial pathogens.


Subject(s)
Amine Oxidase (Copper-Containing)/analysis , Bacteria/metabolism , Diamines/metabolism , Enzyme Assays/methods , Vagina/microbiology , Vaginosis, Bacterial/diagnosis , Vaginosis, Bacterial/enzymology , Adult , Amine Oxidase (Copper-Containing)/metabolism , Bacteria/isolation & purification , Diamines/analysis , Female , Humans , Vagina/enzymology , Vaginal Smears , Vaginosis, Bacterial/microbiology , Young Adult
3.
Toxicol Appl Pharmacol ; 285(3): 198-206, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25818602

ABSTRACT

Any vaginal product that alters the mucosal environment and impairs the immune barrier increases the risk of sexually transmitted infections, especially HIV infection, which thrives on mucosal damage and inflammation. The FDA-recommended rabbit vaginal irritation (RVI) model serves as a first line selection tool for vaginal products; however, for decades it has been limited to histopathology scoring, insufficient to select safe anti-HIV microbicides. In this study we incorporate to the RVI model a novel quantitative nuclease protection assay (qNPA) to quantify mRNA levels of 25 genes representing leukocyte differentiation markers, toll-like receptors (TLR), cytokines, chemokines, epithelial repair, microbicidal and vascular markers, by designing two multiplex arrays. Tissue sections were obtained from 36 rabbits (6 per treatment arm) after 14 daily applications of a placebo gel, saline, 4% nonoxynol-9 (N-9), and three combinations of the anti-HIV microbicides tenofovir (TFV) and UC781 in escalating concentrations (highest: 10% TFV+2.5%UC781). Results showed that increased expression levels of toll-like receptor (TLR)-4, interleukin (IL)-1ß, CXCL8, epithelial membrane protein (EMP)-1 (P<0.05), and decreased levels of TLR2 (P<0.05), TLR3 and bactericidal permeability increasing protein (BPI) (P<0.001) were associated with cervicovaginal mucosal alteration (histopathology). Seven markers showed a significant linear trend predicting epithelial damage (up with CD4, IL-1ß, CXCL8, CCL2, CCL21, EMP1 and down with BPI). Despite the low tissue damage RVI scores, the high-dose microbicide combination gel caused activation of HIV host cells (SLC and CD4) while N-9 caused proinflammatory gene upregulation (IL-8 and TLR4) suggesting a potential for increasing risk of HIV via different mechanisms depending on the chemical nature of the test product.


Subject(s)
Drug Evaluation, Preclinical , Nuclease Protection Assays/methods , Transcriptome , Vagina/drug effects , Adenine/administration & dosage , Adenine/adverse effects , Adenine/analogs & derivatives , Animals , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/adverse effects , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Combinations , Evaluation Studies as Topic , Female , Host-Pathogen Interactions , Immunohistochemistry , Inflammation/pathology , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Interleukin-8/genetics , Interleukin-8/metabolism , Mucous Membrane/drug effects , Mucous Membrane/metabolism , Nonoxynol/administration & dosage , Nonoxynol/adverse effects , Oligopeptides/genetics , Oligopeptides/metabolism , Organophosphonates/administration & dosage , Organophosphonates/adverse effects , Rabbits , Tenofovir , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Vagina/pathology
4.
J Transl Med ; 10: 144, 2012 Jul 11.
Article in English | MEDLINE | ID: mdl-22784600

ABSTRACT

Europrise is a Network of Excellence supported by the European Commission within the 6th Framework programme from 2007 to 2012. The Network has involved over 50 institutions from 13 European countries together with 3 industrial partners and 6 African countries. The Network encompasses an integrated program of research, training, dissemination and advocacy within the field of HIV vaccines and microbicides. A central and timely theme of the Network is the development of the unique concept of co-usage of vaccines and microbicides. Training of PhD students has been a major task, and some of these post-graduate students have here summarized novel ideas emanating from presentations at the last annual Europrise meeting in Prague. The latest data and ideas concerning HIV vaccine and microbicide studies are included in this review; these studies are so recent that the majority have yet to be published. Data were presented and discussed concerning novel immunisation strategies; microbicides and PrEP (alone and in combination with vaccines); mucosal transmission of HIV/SIV; mucosal vaccination; novel adjuvants; neutralizing antibodies; innate immune responses; HIV/SIV pathogenesis and disease progression; new methods and reagents. These - necessarily overlapping topics - are comprehensively summarised by the Europrise students in the context of other recent exciting data.


Subject(s)
AIDS Vaccines , Anti-HIV Agents/therapeutic use , Drug Design , HIV Infections/immunology , Animals , HIV Infections/prevention & control , Humans
5.
PLoS One ; 5(10): e13592, 2010 Oct 27.
Article in English | MEDLINE | ID: mdl-21048963

ABSTRACT

BACKGROUND: Over the last decade several phase III microbicides trials have been conducted in developing countries. However, laboratories in resource constrained settings do not always have the experience, infrastructure, and the capacity to deliver laboratory data meeting the high standards of clinical trials. This paper describes the design and outcomes of a laboratory quality assurance program which was implemented during a phase III clinical trial evaluating the efficacy of the candidate microbicide Cellulose Sulfate 6% (CS) [1]. METHODOLOGY: In order to assess the effectiveness of CS for HIV and STI prevention, a phase III clinical trial was conducted in 5 sites: 3 in Africa and 2 in India. The trial sponsor identified an International Central Reference Laboratory (ICRL), responsible for the design and management of a quality assurance program, which would guarantee the reliability of laboratory data. The ICRL provided advice on the tests, assessed local laboratories, organized trainings, conducted supervision visits, performed re-tests, and prepared control panels. Local laboratories were provided with control panels for HIV rapid tests and Chlamydia trachomatis/Neisseria gonorrhoeae (CT/NG) amplification technique. Aliquots from respective control panels were tested by local laboratories and were compared with results obtained at the ICRL. RESULTS: Overall, good results were observed. However, discordances between the ICRL and site laboratories were identified for HIV and CT/NG results. One particular site experienced difficulties with HIV rapid testing shortly after study initiation. At all sites, DNA contamination was identified as a cause of invalid CT/NG results. Both problems were timely detected and solved. Through immediate feedback, guidance and repeated training of laboratory staff, additional inaccuracies were prevented. CONCLUSIONS: Quality control guidelines when applied in field laboratories ensured the reliability and validity of final study data. It is essential that sponsors provide adequate resources for implementation of such comprehensive technical assessment and monitoring systems. TRIAL REGISTRATION: ClinicalTrials.gov NCT00153777 and Current Controlled Trials ISRCTN95638385.


Subject(s)
Anti-Infective Agents, Local/therapeutic use , Africa , Developing Countries , Humans , India , Quality Control
6.
AIDS ; 22 Suppl 5: S117-25, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19098472

ABSTRACT

OBJECTIVES: To estimate HIV and sexually transmitted infection (STI) prevalence within the general population of Mysore district, and to examine differences in the distribution of risk factors associated with HIV prevalence stratified by sex. METHODS: A community-based study was conducted in Mysore, Karnataka state, southern India, between October 2005 and November 2006; final sample size 4653. A face-to-face interview was conducted, and blood and urine specimens collected to measure HIV and STI prevalences. Risk factors for HIV among men and women were examined using weighted and clustered logistic regression. RESULTS: Weighted HIV prevalence was 0.8% [95% confidence interval (CI) 0.52-1.09] overall and 0.7% (0.35-1.08) and 0.9% (0.51-1.37) in rural and urban populations, respectively. The prevalence of syphilis, gonorrhoea and chlamydial infection was 2.8% for men and 1.8% for women. In multivariate analysis, higher HIV prevalence was associated with ever having used a condom [odds ratio (OR) 2.75, 95% CI 1.01-7.47] and number of lifetime partners for men (OR 6.9, 95% CI 2.18-21.91). For women, HIV infection was associated with condom use at last sexual intercourse (OR 10.51, 95% CI 2.05-53.79), number of lifetime partners and reporting 'don't know' for whether ever had anal sex (OR 9.10, 95% CI 1.14-72.34). CONCLUSIONS: HIV prevalence in the general population of Mysore was found to be comparable to recent prevalence estimates for Karnataka state, and also similar to recent prevalence estimates from antenatal clinic attenders for the district. Few modifiable risk factors for HIV infection were identified. There is evidence from this study that high-risk behaviour may have been underreported, but the prevalence of STI was generally low.


Subject(s)
HIV Infections/epidemiology , Adolescent , Adult , Age Distribution , Condoms/statistics & numerical data , Epidemiologic Methods , Female , HIV Infections/transmission , Humans , India/epidemiology , Male , Middle Aged , Prevalence , Risk-Taking , Rural Health/statistics & numerical data , Sexual Behavior/statistics & numerical data , Sexual Partners , Sexually Transmitted Diseases/epidemiology , Sexually Transmitted Diseases/transmission , Urban Health/statistics & numerical data , Young Adult
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