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Bej R, Stevens CA, Nie C, Ludwig K, Degen GD, Kerkhoff Y, Pigaleva M, Adler JM, Bustos NA, Page TM, Trimpert J, Block S, Kaufer BB, Ribbeck K, Haag R. Mucus-Inspired Self-Healing Hydrogels: A Protective Barrier for Cells against Viral Infection. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2401745. [PMID: 38815174 DOI: 10.1002/adma.202401745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 05/16/2024] [Indexed: 06/01/2024]
Abstract
Mucus is a dynamic biological hydrogel, composed primarily of the glycoprotein mucin, exhibits unique biophysical properties and forms a barrier protecting cells against a broad-spectrum of viruses. Here, this work develops a polyglycerol sulfate-based dendronized mucin-inspired copolymer (MICP-1) with ≈10% repeating units of activated disulfide as cross-linking sites. Cryo-electron microscopy (Cryo-EM) analysis of MICP-1 reveals an elongated single-chain fiber morphology. MICP-1 shows potential inhibitory activity against many viruses such as herpes simplex virus 1 (HSV-1) and SARS-CoV-2 (including variants such as Delta and Omicron). MICP-1 produces hydrogels with viscoelastic properties similar to healthy human sputum and with tuneable microstructures using linear and branched polyethylene glycol-thiol (PEG-thiol) as cross-linkers. Single particle tracking microrheology, electron paramagnetic resonance (EPR) and cryo-scanning electron microscopy (Cryo-SEM) are used to characterize the network structures. The synthesized hydrogels exhibit self-healing properties, along with viscoelastic properties that are tuneable through reduction. A transwell assay is used to investigate the hydrogel's protective properties against viral infection against HSV-1. Live-cell microscopy confirms that these hydrogels can protect underlying cells from infection by trapping the virus, due to both network morphology and anionic multivalent effects. Overall, this novel mucin-inspired copolymer generates mucus-mimetic hydrogels on a multi-gram scale. These hydrogels can be used as models for disulfide-rich airway mucus research, and as biomaterials.
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Affiliation(s)
- Raju Bej
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Corey Alfred Stevens
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Chuanxiong Nie
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - Kai Ludwig
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - George D Degen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Yannic Kerkhoff
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - Marina Pigaleva
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - Julia M Adler
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Strasse 7-13, 14163, Berlin, Germany
| | - Nicole A Bustos
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Taylor M Page
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - Jakob Trimpert
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Strasse 7-13, 14163, Berlin, Germany
| | - Stephan Block
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
| | - Benedikt B Kaufer
- Institut für Virologie, Freie Universität Berlin, Robert-von-Ostertag-Strasse 7-13, 14163, Berlin, Germany
| | - Katharina Ribbeck
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Rainer Haag
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195, Berlin, Germany
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Dong M, Dong Y, Bai J, Li H, Ma X, Li B, Wang C, Li H, Qi W, Wang Y, Fan A, Han C, Xue F. Interactions between microbiota and cervical epithelial, immune, and mucus barrier. Front Cell Infect Microbiol 2023; 13:1124591. [PMID: 36909729 PMCID: PMC9998931 DOI: 10.3389/fcimb.2023.1124591] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 01/31/2023] [Indexed: 02/26/2023] Open
Abstract
The female reproductive tract harbours hundreds of bacterial species and produces numerous metabolites. The uterine cervix is located between the upper and lower parts of the female genital tract. It allows sperm and birth passage and hinders the upward movement of microorganisms into a relatively sterile uterus. It is also the predicted site for sexually transmitted infection (STI), such as Chlamydia, human papilloma virus (HPV), and human immunodeficiency virus (HIV). The healthy cervicovaginal microbiota maintains cervical epithelial barrier integrity and modulates the mucosal immune system. Perturbations of the microbiota composition accompany changes in microbial metabolites that induce local inflammation, damage the cervical epithelial and immune barrier, and increase susceptibility to STI infection and relative disease progression. This review examined the intimate interactions between the cervicovaginal microbiota, relative metabolites, and the cervical epithelial-, immune-, and mucus barrier, and the potent effect of the host-microbiota interaction on specific STI infection. An improved understanding of cervicovaginal microbiota regulation on cervical microenvironment homeostasis might promote advances in diagnostic and therapeutic approaches for various STI diseases.
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Affiliation(s)
- Mengting Dong
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Yalan Dong
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Junyi Bai
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Huanrong Li
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Xiaotong Ma
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Bijun Li
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Chen Wang
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Huiyang Li
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Wenhui Qi
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Yingmei Wang
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Aiping Fan
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
| | - Cha Han
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
- *Correspondence: Cha Han, ; Fengxia Xue,
| | - Fengxia Xue
- Department of Obstetrics and Gynaecology, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Female Reproductive Health and Eugenic, Department of Gynecology and Obstetrics, Tianjin Medical University General Hospital, Tianjin, China
- *Correspondence: Cha Han, ; Fengxia Xue,
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Bej R, Haag R. Mucus-Inspired Dynamic Hydrogels: Synthesis and Future Perspectives. J Am Chem Soc 2022; 144:20137-20152. [PMID: 36074739 PMCID: PMC9650700 DOI: 10.1021/jacs.1c13547] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/30/2022]
Abstract
Mucus hydrogels at biointerfaces are crucial for protecting against foreign pathogens and for the biological functions of the underlying cells. Since mucus can bind to and host both viruses and bacteria, establishing a synthetic model system that can emulate the properties and functions of native mucus and can be synthesized at large scale would revolutionize the mucus-related research that is essential for understanding the pathways of many infectious diseases. The synthesis of such biofunctional hydrogels in the laboratory is highly challenging, owing to their complex chemical compositions and the specific chemical interactions that occur throughout the gel network. In this perspective, we discuss the basic chemical structures and diverse physicochemical interactions responsible for the unique properties and functions of mucus hydrogels. We scrutinize the different approaches for preparing mucus-inspired hydrogels, with specific examples. We also discuss recent research and what it reveals about the challenges that must be addressed and the opportunities to be considered to achieve desirable de novo synthetic mucus hydrogels.
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Affiliation(s)
- Raju Bej
- Institute for Chemistry and
Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - Rainer Haag
- Institute for Chemistry and
Biochemistry, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
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das Neves J, Sverdlov Arzi R, Sosnik A. Molecular and cellular cues governing nanomaterial-mucosae interactions: from nanomedicine to nanotoxicology. Chem Soc Rev 2021; 49:5058-5100. [PMID: 32538405 DOI: 10.1039/c8cs00948a] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mucosal tissues constitute the largest interface between the body and the surrounding environment and they regulate the access of molecules, supramolecular structures, particulate matter, and pathogens into it. All mucosae are characterized by an outer mucus layer that protects the underlying cells from physicochemical, biological and mechanical insults, a mono-layered or stratified epithelium that forms tight junctions and controls the selective transport of solutes across it and associated lymphoid tissues that play a sentinel role. Mucus is a gel-like material comprised mainly of the glycoprotein mucin and water and it displays both hydrophilic and hydrophobic domains, a net negative charge, and high porosity and pore interconnectivity, providing an efficient barrier for the absorption of therapeutic agents. To prolong the residence time, absorption and bioavailability of a broad spectrum of active compounds upon mucosal administration, mucus-penetrating and mucoadhesive particles have been designed by tuning the chemical composition, the size, the density, and the surface properties. The benefits of utilizing nanomaterials that interact intimately with mucosae by different mechanisms in the nanomedicine field have been extensively reported. To ensure the safety of these nanosystems, their compatibility is evaluated in vitro and in vivo in preclinical and clinical trials. Conversely, there is a growing concern about the toxicity of nanomaterials dispersed in air and water effluents that unintentionally come into contact with the airways and the gastrointestinal tract. Thus, deep understanding of the key nanomaterial properties that govern the interplay with mucus and tissues is crucial for the rational design of more efficient drug delivery nanosystems (nanomedicine) and to anticipate the fate and side-effects of nanoparticulate matter upon acute or chronic exposure (nanotoxicology). This review initially overviews the complex structural features of mucosal tissues, including the structure of mucus, the epithelial barrier, the mucosal-associated lymphatic tissues and microbiota. Then, the most relevant investigations attempting to identify and validate the key particle features that govern nanomaterial-mucosa interactions and that are relevant in both nanomedicine and nanotoxicology are discussed in a holistic manner. Finally, the most popular experimental techniques and the incipient use of mathematical and computational models to characterize these interactions are described.
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Affiliation(s)
- José das Neves
- i3S - Instituto de Investigação e Inovação em Saúde & INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
| | - Roni Sverdlov Arzi
- Laboratory of Pharmaceutical Nanomaterials Science, Department of Materials Science and Engineering, Technion-Israel Institute of Technology, De-Jur Building, Office 607, Haifa, 3200003, Israel.
| | - Alejandro Sosnik
- Laboratory of Pharmaceutical Nanomaterials Science, Department of Materials Science and Engineering, Technion-Israel Institute of Technology, De-Jur Building, Office 607, Haifa, 3200003, Israel.
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5
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Bruxelle JF, Trattnig N, Mureithi MW, Landais E, Pantophlet R. HIV-1 Entry and Prospects for Protecting against Infection. Microorganisms 2021; 9:microorganisms9020228. [PMID: 33499233 PMCID: PMC7911371 DOI: 10.3390/microorganisms9020228] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/19/2022] Open
Abstract
Human Immunodeficiency Virus type-1 (HIV-1) establishes a latent viral reservoir soon after infection, which poses a major challenge for drug treatment and curative strategies. Many efforts are therefore focused on blocking infection. To this end, both viral and host factors relevant to the onset of infection need to be considered. Given that HIV-1 is most often transmitted mucosally, strategies designed to protect against infection need to be effective at mucosal portals of entry. These strategies need to contend also with cell-free and cell-associated transmitted/founder (T/F) virus forms; both can initiate and establish infection. This review will discuss how insight from the current model of HIV-1 mucosal transmission and cell entry has highlighted challenges in developing effective strategies to prevent infection. First, we examine key viral and host factors that play a role in transmission and infection. We then discuss preventive strategies based on antibody-mediated protection, with emphasis on targeting T/F viruses and mucosal immunity. Lastly, we review treatment strategies targeting viral entry, with focus on the most clinically advanced entry inhibitors.
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Affiliation(s)
- Jean-François Bruxelle
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- Correspondence: (J.-F.B.); (R.P.)
| | - Nino Trattnig
- Chemical Biology and Drug Discovery, Utrecht University, 3584 CG Utrecht, The Netherlands;
| | - Marianne W. Mureithi
- KAVI—Institute of Clinical Research, College of Health Sciences, University of Nairobi, P.O. Box, Nairobi 19676–00202, Kenya;
| | - Elise Landais
- IAVI Neutralizing Antibody Center, La Jolla, CA 92037, USA;
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Ralph Pantophlet
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
- Correspondence: (J.-F.B.); (R.P.)
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Hoang T, Toler E, DeLong K, Mafunda NA, Bloom SM, Zierden HC, Moench TR, Coleman JS, Hanes J, Kwon DS, Lai SK, Cone RA, Ensign LM. The cervicovaginal mucus barrier to HIV-1 is diminished in bacterial vaginosis. PLoS Pathog 2020; 16:e1008236. [PMID: 31971984 PMCID: PMC6999914 DOI: 10.1371/journal.ppat.1008236] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 02/04/2020] [Accepted: 11/25/2019] [Indexed: 11/19/2022] Open
Abstract
Bacterial vaginosis (BV), a condition in which the vaginal microbiota consists of community of obligate and facultative anaerobes rather than dominated by a single species of Lactobacillus, affects ~30% of women in the US. Women with BV are at 60% increased risk for HIV acquisition and are 3-times more likely to transmit HIV to an uninfected partner. As cervicovaginal mucus (CVM) is the first line of defense against mucosal pathogens and the home of the resident vaginal microbiota, we hypothesized the barrier function of CVM to HIV may be diminished in BV. Here, we characterized CVM properties including pH, lactic acid content, and Nugent score to correlate with the microbiota community composition, which was confirmed by 16S rDNA sequencing on a subset of samples. We then quantified the mobility of fluorescently-labeled HIV virions and nanoparticles to characterize the structural and adhesive barrier properties of CVM. Our analyses included women with Nugent scores categorized as intermediate (4–6) and BV (7–10), women that were either symptomatic or asymptomatic, and a small group of women before and after antibiotic treatment for symptomatic BV. Overall, we found that HIV virions had significantly increased mobility in CVM from women with BV compared to CVM from women with Lactobacillus crispatus-dominant microbiota, regardless of whether symptoms were present. We confirmed using nanoparticles and scanning electron microscopy that the impaired barrier function was due to reduced adhesive barrier properties without an obvious degradation of the physical CVM pore structure. We further confirmed a similar increase in HIV mobility in CVM from women with Lactobacillus iners-dominant microbiota, the species most associated with transitions to BV and that persists after antibiotic treatment for BV. Our findings advance the understanding of the protective role of mucus and highlight the interplay between vaginal microbiota and the innate barrier function mucus. Bacterial vaginosis (BV), a condition characterized by the depletion of lactobacillus bacteria in the vagina, is the most common vaginal condition in reproductive age women. BV has been associated with many adverse reproductive and sexual health outcomes, including increased risk of HIV infection. Cervicovaginal mucus is the home to vaginal bacteria and acts as a first line of defense to protect the underlying tissues and cells from infection. Here, we studied the barrier properties of mucus from women with BV compared to women with vaginal bacteria dominated by lactobacilli. We found that mucus from women with BV and women with Lactobacillus iners were permissive to HIV-1, which may allow the virus to more easily reach target cells. These findings are in agreement with the observed increased risk for HIV acquisition seen in women with BV and L. iners bacteria. Furthermore, we found that the barrier against HIV is diminished in women with BV regardless of whether they have symptoms. Our findings highlight the important, yet unexplored interactions between the mucus barrier and the vaginal microbiota and the implications for human health.
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Affiliation(s)
- Thuy Hoang
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Emily Toler
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kevin DeLong
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Nomfuneko A. Mafunda
- Ragon Institute of MGH, MIT, and Harvard, Massachusetts General Hospital, Cambridge, Massachusetts, United States of America
| | - Seth M. Bloom
- Ragon Institute of MGH, MIT, and Harvard, Massachusetts General Hospital, Cambridge, Massachusetts, United States of America
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Hannah C. Zierden
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Thomas R. Moench
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jenell S. Coleman
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Justin Hanes
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Douglas S. Kwon
- Ragon Institute of MGH, MIT, and Harvard, Massachusetts General Hospital, Cambridge, Massachusetts, United States of America
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
| | - Samuel K. Lai
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, UNC/NCSU Joint Department of Biomedical Engineering, Department of Microbiology & Immunology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Richard A. Cone
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Laura M. Ensign
- The Center for Nanomedicine, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Ophthalmology, The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
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Comparisons of Human Immunodeficiency Virus Type 1 Envelope Variants in Blood and Genital Fluids near the Time of Male-to-Female Transmission. J Virol 2019; 93:JVI.01769-18. [PMID: 30996101 DOI: 10.1128/jvi.01769-18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 03/15/2019] [Indexed: 11/20/2022] Open
Abstract
To better understand the transmission of human immunodeficiency virus type 1 (HIV-1), the genetic characteristics of blood and genital viruses from males were compared to those of the imputed founding virus population in their female partners. Initially serodiscordant heterosexual African couples with sequence-confirmed male-to-female HIV-1 transmission and blood and genital specimens collected near the time of transmission were studied. Single viral templates from blood plasma and genital tract RNA and DNA were sequenced across HIV-1 env gp160. Eight of 29 couples examined yielded viral sequences from both tissues. Analysis of these couples' sequences demonstrated, with one exception, that the women's founding viral populations arose from a single viral variant and were CCR5 tropic, even though CXCR4 variants were detected within four males. The median genetic distance of the imputed most recent common ancestor of the women's founder viruses showed that they were closer to the semen viruses than to the blood viruses of their transmitting male partner, but this finding was biased by detection of a greater number of viral clades in the blood. Using multiple assays, the blood and genital viruses were consistently found to be compartmentalized in only two of eight men. No distinct amino acid signatures in the men's viruses were found to link to the women's founders, nor did the women's env sequences have shorter variable loops or fewer N-linked glycosylation sites. The lack of selective factors, except for coreceptor tropism, is consistent with others' findings in male-to-female and high-risk transmissions. The infrequent compartmentalization between the transmitters' blood and semen viruses suggests that cell-free blood virus likely includes HIV-1 sequences representative of those of viruses in semen.IMPORTANCE Mucosal transmissions account for the majority of HIV-1 infections. Identification of the viral characteristics associated with transmission would facilitate vaccine design. This study of HIV strains from transmitting males and their seroconverting female partners found that the males' genital tract viruses were rarely distinct from the blood variants. The imputed founder viruses in women were genetically similar to both the blood and genital tract variants of their male partners, indicating a lack of evidence for genital tract-specific lineages. These findings suggest that targeting vaccine responses to variants found in blood are likely to also protect from genital tract variants.
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8
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Sims LB, Frieboes HB, Steinbach-Rankins JM. Nanoparticle-mediated drug delivery to treat infections in the female reproductive tract: evaluation of experimental systems and the potential for mathematical modeling. Int J Nanomedicine 2018; 13:2709-2727. [PMID: 29760551 PMCID: PMC5937491 DOI: 10.2147/ijn.s160044] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A variety of drug-delivery platforms have been employed to deliver therapeutic agents across cervicovaginal mucus (CVM) and the vaginal mucosa, offering the capability to increase the longevity and retention of active agents to treat infections of the female reproductive tract (FRT). Nanoparticles (NPs) have been shown to improve retention, diffusion, and cell-specific targeting via specific surface modifications, relative to other delivery platforms. In particular, polymeric NPs represent a promising option that has shown improved distribution through the CVM. These NPs are typically fabricated from nontoxic, non-inflammatory, US Food and Drug Administration-approved polymers that improve biocompatibility. This review summarizes recent experimental studies that have evaluated NP transport in the FRT, and highlights research areas that more thoroughly and efficiently inform polymeric NP design, including mathematical modeling. An overview of the in vitro, ex vivo, and in vivo NP studies conducted to date – whereby transport parameters are determined, extrapolated, and validated – is presented first. The impact of different NP design features on transport through the FRT is summarized, and gaps that exist due to the limitations of iterative experimentation alone are identified. The potential of mathematical modeling to complement the characterization and evaluation of diffusion and transport of delivery vehicles and active agents through the CVM and mucosa is discussed. Lastly, potential advancements combining experimental and mathematical knowledge are suggested to inform next-generation NP designs, such that infections in the FRT may be more effectively treated.
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Affiliation(s)
- Lee B Sims
- Department of Bioengineering, University of Louisville, Louisville, KY, USA
| | - Hermann B Frieboes
- Department of Bioengineering, University of Louisville, Louisville, KY, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, KY, USA.,Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA
| | - Jill M Steinbach-Rankins
- Department of Bioengineering, University of Louisville, Louisville, KY, USA.,Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA.,Department of Microbiology and Immunology, University of Louisville, Louisville, KY, USA.,Center for Predictive Medicine, University of Louisville, Louisville, KY, USA
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9
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Bansil R, Turner BS. The biology of mucus: Composition, synthesis and organization. Adv Drug Deliv Rev 2018; 124:3-15. [PMID: 28970050 DOI: 10.1016/j.addr.2017.09.023] [Citation(s) in RCA: 339] [Impact Index Per Article: 56.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/24/2017] [Accepted: 09/27/2017] [Indexed: 02/06/2023]
Abstract
In this review we discuss mucus, the viscoelastic secretion from goblet or mucous producing cells that lines the epithelial surfaces of all organs exposed to the external world. Mucus is a complex aqueous fluid that owes its viscoelastic, lubricating and hydration properties to the glycoprotein mucin combined with electrolytes, lipids and other smaller proteins. Electron microscopy of mucosal surfaces reveals a highly convoluted surface with a network of fibers and pores of varying sizes. The major structural and functional component, mucin is a complex glycoprotein coded by about 20 mucin genes which produce a protein backbone having multiple tandem repeats of Serine, Threonine (ST repeats) where oligosaccharides are covalently O-linked. The N- and C-terminals of this apoprotein contain other domains with little or no glycosylation but rich in cysteines leading to dimerization and further multimerization via SS bonds. The synthesis of this complex protein starts in the endoplasmic reticulum with the formation of the apoprotein and is further modified via glycosylation in the cis and medial Golgi and packaged into mucin granules via Ca2+ bridging of the negative charges on the oligosaccharide brush in the trans Golgi. The mucin granules fuse with the plasma membrane of the secretory cells and following activation by signaling molecules release Ca2+ and undergo a dramatic change in volume due to hydration of the highly negatively charged polymer brush leading to exocytosis from the cells and forming the mucus layer. The rheological properties of mucus and its active component mucin and its mucoadhesivity are briefly discussed in light of their importance to mucosal drug delivery.
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10
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Ren X, Tian Y, Liu L, Liu X. A reaction–diffusion within-host HIV model with cell-to-cell transmission. J Math Biol 2018; 76:1831-1872. [DOI: 10.1007/s00285-017-1202-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 12/26/2017] [Indexed: 02/07/2023]
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11
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Han L, Taub R, Jensen JT. Cervical mucus and contraception: what we know and what we don't. Contraception 2017; 96:310-321. [DOI: 10.1016/j.contraception.2017.07.168] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 07/17/2017] [Accepted: 07/28/2017] [Indexed: 01/09/2023]
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12
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Ernst M, John T, Guenther M, Wagner C, Schaefer UF, Lehr CM. A Model for the Transient Subdiffusive Behavior of Particles in Mucus. Biophys J 2017; 112:172-179. [PMID: 28076809 PMCID: PMC5233549 DOI: 10.1016/j.bpj.2016.11.900] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 10/28/2016] [Accepted: 11/21/2016] [Indexed: 10/20/2022] Open
Abstract
In this study we have applied a model to explain the reported subdiffusion of particles in mucus, based on the measured mean squared displacements (MSD). The model considers Brownian diffusion of particles in a confined geometry, made from permeable membranes. The applied model predicts a normal diffusive behavior at very short and long time lags, as observed in several experiments. In between these timescales, we find that the "subdiffusive" regime is only a transient effect, MSD∝τα,α<1. The only parameters in the model are the diffusion-coefficients at the limits of very short and long times, and the distance between the permeable membranes L. Our numerical results are in agreement with published experimental data for realistic assumptions of these parameters. Finally, we show that only particles with a diameter less than 40 nm are able to pass through a mucus layer by passive Brownian motion.
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Affiliation(s)
- Matthias Ernst
- Faculty of Engineering, Department of Applied Mathematics, University of Applied Sciences, Saarbrücken, Germany
| | - Thomas John
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany
| | - Marco Guenther
- Faculty of Engineering, Department of Applied Mathematics, University of Applied Sciences, Saarbrücken, Germany
| | - Christian Wagner
- Department of Experimental Physics, Saarland University, Saarbrücken, Germany; Physics and Materials Science Research Unit, University of Luxembourg, Luxembourg, Luxembourg
| | - Ulrich F Schaefer
- Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University, Saarbrücken, Germany
| | - Claus-Michael Lehr
- Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University, Saarbrücken, Germany; Helmholtz Institute for Pharmaceutical Research Saarland, Saarland University, Saarbrücken, Germany.
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13
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Bastholm SK, Samson MH, Becher N, Hansen LK, Stubbe PR, Chronakis IS, Nexo E, Uldbjerg N. Trefoil factor peptide 3 is positively correlated with the viscoelastic properties of the cervical mucus plug. Acta Obstet Gynecol Scand 2016; 96:47-52. [PMID: 27731893 DOI: 10.1111/aogs.13038] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 10/07/2016] [Indexed: 11/27/2022]
Abstract
INTRODUCTION The viscoelastic properties of the cervical mucus plug are considered essential for the occlusion of the cervical canal and thereby for protection against ascending infections during pregnancy. Factors controlling this property are virtually unknown. This study explores a possible role of trefoil factor peptides 1, 2 and 3 (TFF1-3); peptides believed to influence mucus viscosity. MATERIAL AND METHODS The study is based on spontaneously shed cervical mucus plugs from 14 women in active labor. The viscoelastic properties; the elastic modulus (G') and the viscous modulus (G") were determined by an oscillatory rheometer. The concentrations of TFF1-3 were measured by an in-house enzyme-linked immunosorbent assay. Associations were analyzed by random-effects generalized least-squares regression analyses. RESULTS Median (range) concentrations of TFF1, TFF2 and TFF3 were 3.1 (1.2-8.6), 1.1 (<0.006-3.7) and 1000 (170-5300) nmol/g cervical mucus plug, respectively. The TFF3 concentration was associated with G' (regression coefficient 11.7 Pa/Log nm; 95% CI 3.0-20.4, p = 0.009) and G" (regression coefficient 3.2 Pa/Log nm; 95% CI 1.5-5.0, p < 0.001). CONCLUSION We suggest that TFF3 plays a role in the viscoelastic properties of the cervical mucus plug.
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Affiliation(s)
- Sara K Bastholm
- Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
| | - Mie H Samson
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Naja Becher
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | - Lea K Hansen
- Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
| | - Peter R Stubbe
- Food Production Engineering Research Group, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ioannis S Chronakis
- Nano-BioScience Research Group, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ebba Nexo
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Uldbjerg
- Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
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14
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Boukari F, Makrogiannis S, Nossal R, Boukari H. Imaging and tracking HIV viruses in human cervical mucus. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:96001. [PMID: 27598560 PMCID: PMC5010625 DOI: 10.1117/1.jbo.21.9.096001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 08/08/2016] [Indexed: 05/14/2023]
Abstract
We describe a systematic approach to image, track, and quantify the movements of HIV viruses embedded in human cervical mucus. The underlying motivation for this study is that, in HIV-infected adults, women account for more than half of all new cases and most of these women acquire the infection through heterosexual contact. The endocervix is believed to be a susceptible site for HIV entry. Cervical mucus, which coats the endocervix, should play a protective role against the viruses. Thus, we developed a methodology to apply time-resolved confocal microscopy to examine the motion of HIV viruses that were added to samples of untreated cervical mucus. From the images, we identified the viruses, tracked them over time, and calculated changes of the statistical mean-squared displacement (MSD) of each virus. Approximately half of tracked viruses appear constrained while the others show mobility with MSDs that are proportional to ??+?2?2, over time range ?, depicting a combination of anomalous diffusion (0<?<0.40) and flow-like behavior. The MSD data also reveal plateaus attributable to possible stalling of the viruses. Although a more extensive study is warranted, these results support the assumption of mucus being a barrier against the motion of these viruses.
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Affiliation(s)
- Fatima Boukari
- Delaware State University, Department of Mathematics, 1200 North Dupont Highway, Dover, Delaware 19901, United States
- Delaware State University, Department of Physics and Engineering, 1200 North Dupont Highway, Dover, Delaware 19901, United States
| | - Sokratis Makrogiannis
- Delaware State University, Department of Physics and Engineering, 1200 North Dupont Highway, Dover, Delaware 19901, United States
- Delaware State University, Delaware Institute of Science and Technology, 1200 North Dupont Highway, Dover, Delaware 19901, United States
| | - Ralph Nossal
- Eunice Kennedy Shriver National Institute of Child and Human Development, National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892, United States
| | - Hacène Boukari
- Delaware State University, Department of Physics and Engineering, 1200 North Dupont Highway, Dover, Delaware 19901, United States
- Delaware State University, Delaware Institute of Science and Technology, 1200 North Dupont Highway, Dover, Delaware 19901, United States
- Address all correspondence to: Hacène Boukari, E-mail:
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15
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Carias AM, Allen SA, Fought AJ, Kotnik Halavaty K, Anderson MR, Jimenez ML, McRaven MD, Gioia CJ, Henning TR, Kersh EN, Smith JM, Pereira LE, Butler K, McNicholl SJM, Hendry RM, Kiser PF, Veazey RS, Hope TJ. Increases in Endogenous or Exogenous Progestins Promote Virus-Target Cell Interactions within the Non-human Primate Female Reproductive Tract. PLoS Pathog 2016; 12:e1005885. [PMID: 27658293 PMCID: PMC5033389 DOI: 10.1371/journal.ppat.1005885] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 08/22/2016] [Indexed: 12/22/2022] Open
Abstract
Currently, there are mounting data suggesting that HIV-1 acquisition in women can be affected by the use of certain hormonal contraceptives. However, in non-human primate models, endogenous or exogenous progestin-dominant states are shown to increase acquisition. To gain mechanistic insights into this increased acquisition, we studied how mucosal barrier function and CD4+ T-cell and CD68+ macrophage density and localization changed in the presence of natural progestins or after injection with high-dose DMPA. The presence of natural or injected progestins increased virus penetration of the columnar epithelium and the infiltration of susceptible cells into a thinned squamous epithelium of the vaginal vault, increasing the likelihood of potential virus interactions with target cells. These data suggest that increasing either endogenous or exogenous progestin can alter female reproductive tract barrier properties and provide plausible mechanisms for increased HIV-1 acquisition risk in the presence of increased progestin levels.
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Affiliation(s)
- Ann M. Carias
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Shannon A. Allen
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Angela J. Fought
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Katarina Kotnik Halavaty
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Meegan R. Anderson
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Maria L. Jimenez
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Michael D. McRaven
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Casey J. Gioia
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Tara R. Henning
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Ellen N. Kersh
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - James M. Smith
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Lara E. Pereira
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Katherine Butler
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - S. Janet M. McNicholl
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - R. Michael Hendry
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Patrick F. Kiser
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Ronald S. Veazey
- Tulane National Primate Research Center, Tulane University School of Medicine, Covington, Louisiana, United States of America
| | - Thomas J. Hope
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
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16
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das Neves J, Nunes R, Rodrigues F, Sarmento B. Nanomedicine in the development of anti-HIV microbicides. Adv Drug Deliv Rev 2016; 103:57-75. [PMID: 26829288 DOI: 10.1016/j.addr.2016.01.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 01/21/2016] [Accepted: 01/21/2016] [Indexed: 12/20/2022]
Abstract
Prevention plays an invaluable role in the fight against HIV/AIDS. The use of microbicides is considered an interesting potential approach for topical pre-exposure prophylaxis of HIV sexual transmission. The prospects of having an effective product available are expected to be fulfilled in the near future as driven by recent and forthcoming results of clinical trials. Different dosage forms and delivery strategies have been proposed and tested for multiple microbicide drug candidates presently at different stages of the development pipeline. One particularly interesting approach comprises the application of nanomedicine principles to the development of novel anti-HIV microbicides, but its implications to efficacy and safety are not yet fully understood. Nanotechnology-based systems, either presenting inherent anti-HIV activity or acting as drug nanocarriers, may significantly influence features such as drug solubility, stability of active payloads, drug release, interactions between active moieties and virus/cells, intracellular drug delivery, drug targeting, safety, antiviral activity, mucoadhesive behavior, drug distribution and tissue penetration, and pharmacokinetics. The present manuscript provides a comprehensive and holistic overview of these topics as relevant to the development of vaginal and rectal microbicides. In particular, recent advances pertaining inherently active microbicide nanosystems and microbicide drug nanocarriers are discussed.
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Affiliation(s)
- José das Neves
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal; CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde & Instituto Universitário de Ciências da Saúde, Gandra, Portugal.
| | - Rute Nunes
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal; ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Francisca Rodrigues
- REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Bruno Sarmento
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal; INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal; CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde & Instituto Universitário de Ciências da Saúde, Gandra, Portugal.
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17
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Erickson AM, Henry BI, Murray JM, Klasse PJ, Angstmann CN. Predicting first traversal times for virions and nanoparticles in mucus with slowed diffusion. Biophys J 2016; 109:164-72. [PMID: 26153713 DOI: 10.1016/j.bpj.2015.05.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 05/22/2015] [Accepted: 05/28/2015] [Indexed: 02/01/2023] Open
Abstract
Particle-tracking experiments focusing on virions or nanoparticles in mucus have measured mean-square displacements and reported diffusion coefficients that are orders of magnitude smaller than the diffusion coefficients of such particles in water. Accurate description of this subdiffusion is important to properly estimate the likelihood of virions traversing the mucus boundary layer and infecting cells in the epithelium. However, there are several candidate models for diffusion that can fit experimental measurements of mean-square displacements. We show that these models yield very different estimates for the time taken for subdiffusive virions to traverse through a mucus layer. We explain why fits of subdiffusive mean-square displacements to standard diffusion models may be misleading. Relevant to human immunodeficiency virus infection, using computational methods for fractional subdiffusion, we show that subdiffusion in normal acidic mucus provides a more effective barrier against infection than previously thought. By contrast, the neutralization of the mucus by alkaline semen, after sexual intercourse, allows virions to cross the mucus layer and reach the epithelium in a short timeframe. The computed barrier protection from fractional subdiffusion is some orders of magnitude greater than that derived by fitting standard models of diffusion to subdiffusive data.
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Affiliation(s)
- Austen M Erickson
- School of Mathematics and Statistics, UNSW Australia, Sydney, New South Wales, Australia
| | - Bruce I Henry
- School of Mathematics and Statistics, UNSW Australia, Sydney, New South Wales, Australia
| | - John M Murray
- School of Mathematics and Statistics, UNSW Australia, Sydney, New South Wales, Australia
| | - Per Johan Klasse
- Department of Microbiology and Immunology, Weill Cornell Medical College, Cornell University, New York, New York
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18
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Biopolymeric Mucin and Synthetic Polymer Analogs: Their Structure, Function and Role in Biomedical Applications. Polymers (Basel) 2016; 8:polym8030071. [PMID: 30979166 PMCID: PMC6432556 DOI: 10.3390/polym8030071] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 02/23/2016] [Accepted: 02/24/2016] [Indexed: 12/17/2022] Open
Abstract
Mucin networks are viscoelastic fibrillar aggregates formed through the complex self-association of biopolymeric glycoprotein chains. The networks form a lubricious, hydrated protective shield along epithelial regions within the human body. The critical role played by mucin networks in impacting the transport properties of biofunctional molecules (e.g., biogenic molecules, probes, nanoparticles), and its effect on bioavailability are well described in the literature. An alternate perspective is provided in this paper, presenting mucin’s complex network structure, and its interdependent functional characteristics in human physiology. We highlight the recent advances that were achieved through the use of mucin in diverse areas of bioengineering applications (e.g., drug delivery, biomedical devices and tissue engineering). Mucin network formation is a highly complex process, driven by wide variety of molecular interactions, and the network possess structural and chemical variations, posing a great challenge to understand mucin’s bulk behavior. Through this review, the prospective potential of polymer based analogs to serve as mucin mimic is suggested. These analog systems, apart from functioning as an artificial model, reducing the current dependency on animal models, can aid in furthering our fundamental understanding of such complex structures.
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19
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Hormonal Contraceptive Effects on the Vaginal Milieu: Microbiota and Immunity. CURRENT OBSTETRICS AND GYNECOLOGY REPORTS 2016. [DOI: 10.1007/s13669-016-0142-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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20
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Caramella CM, Rossi S, Ferrari F, Bonferoni MC, Sandri G. Mucoadhesive and thermogelling systems for vaginal drug delivery. Adv Drug Deliv Rev 2015; 92:39-52. [PMID: 25683694 DOI: 10.1016/j.addr.2015.02.001] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/29/2015] [Accepted: 02/06/2015] [Indexed: 11/28/2022]
Abstract
This review focuses on two formulation approaches, mucoadhesion and thermogelling, intended for prolonging residence time on vaginal mucosa of medical devices or drug delivery systems, thus improving their efficacy. The review, after a brief description of the vaginal environment and, in particular, of the vaginal secretions that strongly affect in vivo performance of vaginal formulations, deals with the above delivery systems. As for mucoadhesive systems, conventional formulations (gels, tablets, suppositories and emulsions) and novel drug delivery systems (micro-, nano-particles) intended for vaginal administration to achieve either local or systemic effect are reviewed. As for thermogelling systems, poly(ethylene oxide-propylene oxide-ethylene oxide) copolymer-based and chitosan-based formulations are discussed as thermogelling systems. The methods employed for functional characterization of both mucoadhesive and thermogelling drug delivery systems are also briefly described.
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Affiliation(s)
- Carla M Caramella
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy.
| | - Silvia Rossi
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Franca Ferrari
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | | | - Giuseppina Sandri
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
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21
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das Neves J, Nunes R, Machado A, Sarmento B. Polymer-based nanocarriers for vaginal drug delivery. Adv Drug Deliv Rev 2015; 92:53-70. [PMID: 25550217 DOI: 10.1016/j.addr.2014.12.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 11/07/2014] [Accepted: 12/18/2014] [Indexed: 10/24/2022]
Abstract
The vaginal delivery of various drugs is well described and its relevance established in current medical practice. Alongside recent advances and achievements in the fields of pharmaceutical nanotechnology and nanomedicine, there is an increasing interest in the potential use of different nanocarriers for the delivery of old and new pharmacologically active molecules with either therapeutic or prophylactic purposes. Nanosystems of polymeric nature in particular have been investigated over the last years and their interactions with mucosal fluids and tissues, as well as genital tract biodistribution upon vaginal administration, are now better understood. While different applications have been envisioned, most of the current research is focusing in the development of nano-formulations with the potential to inhibit the vaginal transmission of HIV upon sexual intercourse. The present work focuses its discussion on the potential and perils of polymer-based nanocarriers for the vaginal administration of different pharmacologically active molecules.
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22
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Huang BK, Choma MA. Microscale imaging of cilia-driven fluid flow. Cell Mol Life Sci 2015; 72:1095-113. [PMID: 25417211 PMCID: PMC4605231 DOI: 10.1007/s00018-014-1784-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/12/2014] [Accepted: 11/13/2014] [Indexed: 10/24/2022]
Abstract
Cilia-driven fluid flow is important for multiple processes in the body, including respiratory mucus clearance, gamete transport in the oviduct, right-left patterning in the embryonic node, and cerebrospinal fluid circulation. Multiple imaging techniques have been applied toward quantifying ciliary flow. Here, we review common velocimetry methods of quantifying fluid flow. We then discuss four important optical modalities, including light microscopy, epifluorescence, confocal microscopy, and optical coherence tomography, that have been used to investigate cilia-driven flow.
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Affiliation(s)
- Brendan K Huang
- Department of Biomedical Engineering, Yale University, New Haven, USA,
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23
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Mucoadhesive polymers in the design of nano-drug delivery systems for administration by non-parenteral routes: A review. Prog Polym Sci 2014. [DOI: 10.1016/j.progpolymsci.2014.07.010] [Citation(s) in RCA: 333] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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24
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Chappell CA, Rohan LC, Moncla BJ, Wang L, Meyn LA, Bunge K, Hillier SL. The effects of reproductive hormones on the physical properties of cervicovaginal fluid. Am J Obstet Gynecol 2014; 211:226.e1-7. [PMID: 24662718 DOI: 10.1016/j.ajog.2014.03.041] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/04/2014] [Accepted: 03/17/2014] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The purpose of this study was to determine the impact of contraception, menopause, and vaginal flora on the physical and biochemical properties of cervicovaginal fluid (CVF). STUDY DESIGN Vaginal swabs, CVF, and cervicovaginal lavage (CVL) were collected from a total of 165 healthy asymptomatic women including: postmenopausal women (n = 29), women in the proliferative (n = 26) or follicular (n = 27) phase, and women using the levonogestrel intrauterine device (n = 28), depomedroxyprogesterone acetate (n = 28) or combined oral contraceptives (n = 27). Vaginal smears were evaluated using the Nugent score. The osmolality, viscosity, density, and pH of CVL samples were measured. RESULTS CVL from postmenopausal women and women with abnormal vaginal flora was less viscous and had higher pH than premenopausal women and women with normal flora, respectively. Women using hormonal contraceptives had more viscous CVL as compared with premenopausal women not using hormonal contraceptives, but this increase in viscosity was mitigated in the presence of bacterial vaginosis. Women using depomedroxyprogesterone acetate had less total protein in the CVL as compared with women using the levonogestrel intrauterine device, and had similar protein content when compared with postmenopausal women. CONCLUSION The differences in CVL protein content between depomedroxyprogesterone acetate and levonogestrel intrauterine device suggest that type of progesterone and route of delivery impact the vaginal environment. Contraceptive hormone users had more viscous CVL than women not using contraceptives. However, the presence of bacterial vaginosis impacted both the pH and viscosity (regardless of hormonal contraceptive use), demonstrating that vaginal flora has a greater impact on the physical properties of CVF than reproductive hormones.
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25
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Barreto-de-Souza V, Arakelyan A, Margolis L, Vanpouille C. HIV-1 vaginal transmission: cell-free or cell-associated virus? Am J Reprod Immunol 2014; 71:589-99. [PMID: 24730358 DOI: 10.1111/aji.12240] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Accepted: 02/25/2014] [Indexed: 12/28/2022] Open
Abstract
The vast majority of new HIV infections in male-to-female transmission occurs through semen, where HIV-1 is present in two different forms: as free and as cell-associated virus. In the female lower genital tract, semen mixes with female genital secretions that contain various factors, some of which facilitate or inhibit HIV-1 transmission. Next, HIV-1 crosses the genital epithelia, reaches the regional lymph nodes, and disseminates through the female host. Cervico-vaginal mucosa contains multiple barriers, resulting in a low probability of vaginal transmission. However, in some cases, HIV-1 is able to break these barriers. Although the exact mechanisms of how these barriers function remain unclear, their levels of efficiency against cell-free and cell-associated HIV-1 are different, and both cell-free and cell-associated virions seem to use different strategies to overcome these barriers. Understanding the basic mechanisms of HIV-1 vaginal transmission is required for the development of new antiviral strategies to contain HIV-1 epidemics.
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Affiliation(s)
- Victor Barreto-de-Souza
- Section of Intercellular Interactions, Program in Physical Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
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26
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Arakelyan A, Fitzgerald W, Grivel JC, Vanpouille C, Margolis L. Histocultures (tissue explants) in human retrovirology. Methods Mol Biol 2014; 1087:233-48. [PMID: 24158827 DOI: 10.1007/978-1-62703-670-2_19] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Viral pathogenesis is studied predominantly in cultures of primary isolated cells or cell lines. Many retroviruses efficiently replicate only in activated cells. Therefore, in order to become efficient viral producers cells should be artificially activated, a procedure which significantly changes cell physiology. However, for many viral diseases, like HIV-1 and other retroviruses' diseases, critical pathogenic events occur in tissues. Therefore, cell isolation from their native microenvironment prevents single-cell cultures from faithfully reflecting important aspects of cell-cell and cell-pathogen interactions that occur in the context of complex tissue cytoarchitecture. Tissue explants (histocultures) that retain tissue cytoarchitecture and many aspects of cell-cell interactions more faithfully represent in vivo tissue features. Human histocultures constitute an adequate model for studying viral pathogenesis under controlled laboratory conditions. Protocols for various human histocultures as applied to study retroviral pathogenesis, in particular of HIV-1, have been refined by our laboratory and are described in the present publication. Histocultures of human tonsils and lymph nodes, as well as of recto-sigmoid and cervicovaginal tissues can be used to study viral transmission, pathogenesis and as a preclinical platform for antivirals evaluation.
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Affiliation(s)
- Anush Arakelyan
- Section of Intercellular Interactions, Program on Physical Biology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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Turing Patterns from Dynamics of Early HIV Infection. Bull Math Biol 2013; 75:774-95. [DOI: 10.1007/s11538-013-9834-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 03/12/2013] [Indexed: 11/27/2022]
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Abstract
Cervical and vaginal epithelia are primary barriers against HIV type I (HIV-1) entry during male-to-female transmission. Cervical mucus (CM) is produced by the endocervix and forms a layer locally as well as in the vaginal compartment in the form of cervicovaginal mucus (CVM). To study the potential barrier function of each mucus type during HIV-1 transmission, we quantified HIV-1 mobility in CM and CVM ex vivo using fluorescent microscopy. Virions and 200-nm PEGylated beads were digitally tracked and mean-squared displacement was calculated. The mobility of beads increased significantly in CVM compared with CM, consistent with the known decreased mucin concentration of CVM. Unexpectedly, HIV-1 diffusion was significantly hindered in the same CVM samples in which bead diffusion was unhindered. Inhibition of virus transport was envelope-independent. Our results reveal a previously unknown activity in CVM that is capable of impeding HIV-1 mobility to enhance mucosal barrier function.
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das Neves J, Rocha CMR, Gonçalves MP, Carrier RL, Amiji M, Bahia MF, Sarmento B. Interactions of Microbicide Nanoparticles with a Simulated Vaginal Fluid. Mol Pharm 2012; 9:3347-56. [DOI: 10.1021/mp300408m] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- José das Neves
- Laboratory of Pharmaceutical Technology, LTF/CICF,
Faculty of Pharmacy, University of Porto, Porto, Portugal
- CICS−Centro de Investigação
em Ciências da Saúde, Department of Pharmaceutical Sciences,
Instituto Superior de Ciências da Saúde-Norte, CESPU, Gandra,
Portugal
| | - Cristina M. R. Rocha
- REQUIMTE, Department
of Chemical Engineering, Faculty of Engineering, University of Porto,
Porto, Portugal
| | - Maria Pilar Gonçalves
- REQUIMTE, Department
of Chemical Engineering, Faculty of Engineering, University of Porto,
Porto, Portugal
| | - Rebecca L. Carrier
- Department
of Chemical Engineering, Northeastern University, Boston, Massachusetts
02115, United States
| | - Mansoor Amiji
- Department
of Pharmaceutical Sciences, School of Pharmacy, Northeastern University,
Boston, Massachusetts 02115, United States
| | - Maria Fernanda Bahia
- Laboratory of Pharmaceutical Technology, LTF/CICF,
Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Bruno Sarmento
- Laboratory of Pharmaceutical Technology, LTF/CICF,
Faculty of Pharmacy, University of Porto, Porto, Portugal
- CICS−Centro de Investigação
em Ciências da Saúde, Department of Pharmaceutical Sciences,
Instituto Superior de Ciências da Saúde-Norte, CESPU, Gandra,
Portugal
- INEB−Instituto de Engenharia Biomédica, Biomaterials
Division, NEWTherapies Group, Porto, Portugal
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Lisco A, Munawwar A, Introini A, Vanpouille C, Saba E, Feng X, Grivel JC, Singh S, Margolis L. Semen of HIV-1-infected individuals: local shedding of herpesviruses and reprogrammed cytokine network. J Infect Dis 2012; 205:97-105. [PMID: 22107749 PMCID: PMC3242745 DOI: 10.1093/infdis/jir700] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Semen is the main carrier of sexually transmitted viruses, including human immunodeficiency virus type 1 (HIV-1). However, semen is not just a mere passive transporter of virions but also plays an active role in HIV-1 transmission through cytokines and other biological factors. METHODS To study the relationship between viruses and the chemokine-cytokine network in the male genital tract, we measured the concentrations of 21 cytokines/chemokines and the loads of HIV-1 and of 6 herpesviruses in seminal and blood plasma from HIV-1-infected and HIV-uninfected men. RESULTS We found that (1) semen is enriched in cytokines and chemokines that play key roles in HIV-1 infection or transmission; (2) HIV-1 infection changes the chemokine-cytokine network in semen, further enriching it in cytokines that modulate its replication; (3) HIV-1 infection is associated with Epstein-Barr virus (EBV) and cytomegalovirus (CMV) compartmentalized seminal reactivation; (4) CMV and EBV concomitant seminal shedding is associated with higher HIV-1 loads in blood and seminal plasma; and (5) CMV seminal reactivation increases the seminal levels of the CCR5 ligands RANTES and eotaxin, and of the CXCR3 ligand monokine induced by gamma interferon (MIG). CONCLUSIONS HIV-1 infection results in an aberrant production of cytokines and reactivation of EBV and CMV that further changes the seminal cytokine network. The altered seminal milieu in HIV-1 infection may be a determinant of HIV-1 sexual transmission.
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Affiliation(s)
- Andrea Lisco
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
| | - Arshi Munawwar
- Division of Clinical Microbiology, All India Institute of Medical Sciences, New Delhi
| | - Andrea Introini
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
| | - Christophe Vanpouille
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
| | - Elisa Saba
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
- AIDS Immunopathogenesis Unit, San Raffaele Scientific Institute, Milan, Italy
| | - Xingmin Feng
- Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Jean-Charles Grivel
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
| | - Sarman Singh
- Division of Clinical Microbiology, All India Institute of Medical Sciences, New Delhi
| | - Leonid Margolis
- Section of Intercellular Interactions, Eunice-Kennedy Shriver National Institute of Child Health and Human Development, and
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das Neves J, Bahia MF, Amiji MM, Sarmento B. Mucoadhesive nanomedicines: characterization and modulation of mucoadhesion at the nanoscale. Expert Opin Drug Deliv 2011; 8:1085-104. [DOI: 10.1517/17425247.2011.586334] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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das Neves J, Amiji M, Sarmento B. Mucoadhesive nanosystems for vaginal microbicide development: friend or foe? WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2011; 3:389-99. [DOI: 10.1002/wnan.144] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- José das Neves
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Mansoor Amiji
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA, USA
| | - Bruno Sarmento
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Porto, Porto, Portugal
- CICS, Health Sciences Research Center, Department of Pharmaceutical Sciences, Instituto Superior de Ciências da Saúde‐Norte, Gandra, Portugal
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Grivel JC, Shattock RJ, Margolis LB. Selective transmission of R5 HIV-1 variants: where is the gatekeeper? J Transl Med 2011; 9 Suppl 1:S6. [PMID: 21284905 PMCID: PMC3105506 DOI: 10.1186/1479-5876-9-s1-s6] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To enter target cells HIV-1 uses CD4 and a coreceptor. In vivo the coreceptor function is provided either by CCR5 (for R5) or CXCR4 (for X4 HIV-1). Although both R5 and X4 HIV-1 variants are present in body fluids (semen, blood, cervicovaginal and rectal secretions), R5 HIV-1 appears to transmit infection and dominates early stages of HIV disease. Moreover, recent sequence analysis of virus in acute infection shows that, in the majority of cases of transmission, infection is initiated by a single virus. Therefore, the existence of a "gatekeeper" that selects R5 over X4 HIV-1 and that operates among R5 HIV-1 variants has been suggested. In the present review we consider various routes of HIV-transmission and discuss potential gatekeeping mechanisms associated with each of these routes. Although many mechanisms have been identified none of them explains the almost perfect selection of R5 over X4 in HIV-1 transmission. We suggest that instead of one strong gatekeeper there are multiple functional gatekeepers and that their superimposition is sufficient to protect against X4 HIV-1 infection and potentially select among R5 HIV-1 variants. In conclusion, we propose that the principle of multiple barriers is more general and not restricted to protection against X4 HIV-1 but rather can be applied to other phenomena when one factor has a selective advantage over the other(s). In the case of gatekeepers for HIV-1 transmission, the task is to identify them and to decipher their molecular mechanisms. Knowledge of the gatekeepers' localization and function may enable us to enhance existing barriers against R5 transmission and to erect the new ones against all HIV-1 variants.
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Affiliation(s)
- Jean-Charles Grivel
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, USA
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