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Wang W, Li Y, Lin K, Wang X, Tu Y, Zhuo Z. Progress in building clinically relevant patient-derived tumor xenograft models for cancer research. Animal Model Exp Med 2023; 6:381-398. [PMID: 37679891 PMCID: PMC10614132 DOI: 10.1002/ame2.12349] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 08/03/2023] [Indexed: 09/09/2023] Open
Abstract
Patient-derived tumor xenograft (PDX) models, a method involving the surgical extraction of tumor tissues from cancer patients and subsequent transplantation into immunodeficient mice, have emerged as a pivotal approach in translational research, particularly in advancing precision medicine. As the first stage of PDX development, the patient-derived orthotopic xenograft (PDOX) models implant tumor tissue in mice in the corresponding anatomical locations of the patient. The PDOX models have several advantages, including high fidelity to the original tumor, heightened drug sensitivity, and an elevated rate of successful transplantation. However, the PDOX models present significant challenges, requiring advanced surgical techniques and resource-intensive imaging technologies, which limit its application. And then, the humanized mouse models, as well as the zebrafish models, were developed. Humanized mouse models contain a human immune environment resembling the tumor and immune system interplay. The humanized mouse models are a hot topic in PDX model research. Regarding zebrafish patient-derived tumor xenografts (zPDX) and patient-derived organoids (PDO) as promising models for studying cancer and drug discovery, zPDX models are used to transplant tumors into zebrafish as novel personalized medical animal models with the advantage of reducing patient waiting time. PDO models provide a cost-effective approach for drug testing that replicates the in vivo environment and preserves important tumor-related information for patients. The present review highlights the functional characteristics of each new phase of PDX and provides insights into the challenges and prospective developments in this rapidly evolving field.
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Affiliation(s)
- Weijing Wang
- Department of Clinical MedicineShantou University Medical CollegeShantouChina
| | - Yongshu Li
- College of Life SciencesHubei Normal UniversityHuangshiChina
- Shenzhen Institute for Technology InnovationNational Institute of MetrologyShenzhenChina
| | - Kaida Lin
- Department of Clinical MedicineShantou University Medical CollegeShantouChina
| | - Xiaokang Wang
- Department of PharmacyShenzhen Longhua District Central HospitalShenzhenChina
| | - Yanyang Tu
- Research Center, Huizhou Central People's HospitalGuangdong Medical UniversityHuizhou CityChina
| | - Zhenjian Zhuo
- State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
- Laboratory Animal Center, School of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
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2
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Gallay PA, Ramirez CM, Baum MM. Acute antagonism in three-drug combinations for vaginal HIV prevention in humanized mice. Sci Rep 2023; 13:4594. [PMID: 36944714 PMCID: PMC10030891 DOI: 10.1038/s41598-023-31695-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 03/15/2023] [Indexed: 03/23/2023] Open
Abstract
Adolescent girls and young women in low- to middle-income countries are disproportionately at risk of becoming HIV-1 infected. New non-vaccine biomedical products aimed at overcoming this global health challenge need to provide a range of safe, effective, and discreet dosage forms based on the delivery of one or more antiviral compounds. An overarching strategy involves vaginal drug administration through inserts/tablets, gels, films, and intravaginal rings. The approach derives its appeal from being women-controlled and topical, there-by potentially minimizing systemic exposure to the agents and their metabolites. Oral regimens based on tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) are established and effective in HIV-1 pre-exposure prophylaxis (PrEP), and form a promising basis for vaginal PrEP. Here, we used bone marrow/liver/thymus humanized mice to measure the in vivo efficacy against HIV-1 of single and combination antiviral compounds applied vaginally, coupled with data analysis using the Chou-Talalay mathematical model to study the dose-effect characteristics. Unexpectedly, strong antagonism was observed in drug combinations composed of TDF-FTC coupled with a third agent using a different mode of action against HIV-1. The antagonistic effect was remedied when TDF was omitted from the regimen. Our approach provides a translational template for the preclinical, rational, and systematic evaluation of drug combinations for the prevention of HIV-1, and other viral diseases.
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Affiliation(s)
- Philippe A Gallay
- Department of Immunology and Microbiology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - Christina M Ramirez
- Department of Biostatistics, UCLA Fielding School of Public Health, University of California, Los Angeles (UCLA), Los Angeles, CA, USA
| | - Marc M Baum
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA.
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3
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Comparing Current and Next-generation Humanized Mouse Models for Advancing HIV and HIV/Mtb Co-infection Studies. Viruses 2022; 14:v14091927. [PMID: 36146734 PMCID: PMC9500899 DOI: 10.3390/v14091927] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 08/26/2022] [Indexed: 11/23/2022] Open
Abstract
In people living with HIV, Mycobacterium tuberculosis (Mtb) is the major cause of death. Due to the increased morbidity/mortality in co-infection, further research is urgently required. A limiting factor to research in HIV and HIV/Mtb co-infection is the lack of accessible in vivo models. Next-generation humanized mice expressing HLA transgenes report improved human immune reconstitution and functionality, which may better recapitulate human disease. This study compares well-established huNRG mice and next-generation HLA I/II-transgenic (huDRAG-A2) mice for immune reconstitution, disease course, and pathology in HIV and TB. HuDRAG-A2 mice have improved engraftment of key immune cell types involved in HIV and TB disease. Upon intravaginal HIV-1 infection, both models developed significant HIV target cell depletion in the blood and tissues. Upon intranasal Mtb infection, both models sustained high bacterial load within the lungs and tissue dissemination. Some huDRAG-A2 granulomas appeared more classically organized, characterized by focal central necrosis, multinucleated giant cells, and foamy macrophages surrounded by a halo of CD4+ T cells. HIV/Mtb co-infection in huNRG mice trended towards worsened TB pathology and showed potential for modeling co-infection. Both huNRG and huDRAG-A2 mice are viable options for investigating HIV and TB, but the huDRAG-A2 model may offer advantages.
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4
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Gunawardana M, Remedios-Chan M, Sanchez D, Webster S, Castonguay AE, Webster P, Buser C, Moss JA, Trinh M, Beliveau M, Hendrix CW, Marzinke MA, Tuck M, Caprioli RM, Reyzer ML, Kuo J, Gallay PA, Baum MM. Fundamental aspects of long-acting tenofovir alafenamide delivery from subdermal implants for HIV prophylaxis. Sci Rep 2022; 12:8224. [PMID: 35581262 PMCID: PMC9114338 DOI: 10.1038/s41598-022-11020-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 04/15/2022] [Indexed: 01/04/2023] Open
Abstract
Global efforts aimed at preventing human immunodeficiency virus type one (HIV-1) infection in vulnerable populations appear to be stalling, limiting our ability to control the epidemic. Long-acting, controlled drug administration from subdermal implants holds significant potential by reducing the compliance burden associated with frequent dosing. We, and others, are exploring the development of complementary subdermal implant technologies delivering the potent prodrug, tenofovir alafenamide (TAF). The current report addresses knowledge gaps in the preclinical pharmacology of long-acting, subdermal TAF delivery using several mouse models. Systemic drug disposition during TAF implant dosing was explained by a multi-compartment pharmacokinetic (PK) model. Imaging mass spectrometry was employed to characterize the spatial distribution of TAF and its principal five metabolites in local tissues surrounding the implant. Humanized mouse studies determined the effective TAF dose for preventing vaginal and rectal HIV-1 acquisition. Our results represent an important step in the development of a safe and effective TAF implant for HIV-1 prevention.
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Affiliation(s)
- Manjula Gunawardana
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Mariana Remedios-Chan
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Debbie Sanchez
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Simon Webster
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Amalia E Castonguay
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Paul Webster
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - Christopher Buser
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - John A Moss
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA
| | - MyMy Trinh
- Certara Integrated Drug Development, 2000 Peel Street, Suite 570, Montreal, QC, Canada
| | - Martin Beliveau
- Certara Integrated Drug Development, 2000 Peel Street, Suite 570, Montreal, QC, Canada
| | - Craig W Hendrix
- Department of Medicine, Johns Hopkins University, 600 N. Wolfe Street, Baltimore, MD, USA
| | - Mark A Marzinke
- Department of Medicine, Johns Hopkins University, 600 N. Wolfe Street, Baltimore, MD, USA
- Department of Pathology, Johns Hopkins University, 600 N. Wolfe Street/Carnegie 417, Baltimore, MD, USA
| | - Michael Tuck
- Department of Biochemistry, Vanderbilt University, 9160 MRB III, 465 21st Ave. South, Nashville, TN, USA
| | - Richard M Caprioli
- Department of Biochemistry, Vanderbilt University, 9160 MRB III, 465 21st Ave. South, Nashville, TN, USA
| | - Michelle L Reyzer
- Department of Biochemistry, Vanderbilt University, 9160 MRB III, 465 21st Ave. South, Nashville, TN, USA
| | - Joseph Kuo
- Department of Immunology & Microbiology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - Philippe A Gallay
- Department of Immunology & Microbiology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, USA
| | - Marc M Baum
- Department of Chemistry, Oak Crest Institute of Science, 128-132 W. Chestnut Ave., Monrovia, CA, USA.
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5
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Nunes R, Bogas S, Faria MJ, Gonçalves H, Lúcio M, Viseu T, Sarmento B, das Neves J. Electrospun fibers for vaginal administration of tenofovir disoproxil fumarate and emtricitabine in the context of topical pre-exposure prophylaxis. J Control Release 2021; 334:453-462. [PMID: 33961916 DOI: 10.1016/j.jconrel.2021.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/06/2021] [Accepted: 05/03/2021] [Indexed: 12/24/2022]
Abstract
Women are particularly vulnerable to sexual HIV-1 transmission. Oral pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) is highly effective in avoiding new infections in men, but protection has only been shown to be moderate in women. Such differences have been associated, at least partially, to poor drug penetration of the lower female genital tract and the need for strict adherence to continuous daily oral intake of TDF/FTC. On-demand topical microbicide products could help circumvent these limitations. We developed electrospun fibers based on polycaprolactone (PCL fibers) or liposomes associated to poly(vinyl alcohol) (liposomes-in-PVA fibers) for the vaginal co-delivery of TDF and FTC, and assessed their pharmacokinetics in mice. PCL fibers and liposomes-in-PVA fibers were tested for morphological and physicochemical properties using scanning electron microscopy, differential scanning calorimetry and X-ray diffractometry. Fibers featured organoleptic and mechanical properties compatible with their suitable handling and vaginal administration. Fluorescent quenching of mucin in vitro - used as a proxy for mucoadhesion - was intense for PCL fibers, but mild for liposomes-in-PVA fibers. Both fibers were shown safe in vitro and able to rapidly release drug content (15-30 min) under sink conditions. Liposomes-in-PVA fibers allowed increasing genital drug concentrations after a single intravaginal administration when compared to continuous daily treatment for five days with 25-times higher oral doses. For instance, the levels of tenofovir and FTC in vaginal lavage were around 4- and 29-fold higher, respectively. PCL fibers were also superior to oral treatment, although to a minor extent (approximately 2-fold higher drug concentrations in lavage). Vaginal tissue drug levels were generally low for all treatments, while systemic drug exposure was negligible in the case of fibers. These data suggest that proposed fibers may provide an interesting alternative or an ancillary option to oral PrEP in women.
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Affiliation(s)
- 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; CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde, Gandra, Portugal
| | - Sarah Bogas
- CF-UM-UP - Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, Braga, Portugal
| | - Maria João Faria
- CF-UM-UP - Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, Braga, Portugal
| | | | - Marlene Lúcio
- CF-UM-UP - Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, Braga, Portugal; CBMA - Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal.
| | - Teresa Viseu
- CF-UM-UP - Centro de Física das Universidades do Minho e Porto, Departamento de Física, Universidade do Minho, Braga, 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, Gandra, Portugal
| | - 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, Gandra, Portugal.
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6
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Abeynaike S, Paust S. Humanized Mice for the Evaluation of Novel HIV-1 Therapies. Front Immunol 2021; 12:636775. [PMID: 33868262 PMCID: PMC8047330 DOI: 10.3389/fimmu.2021.636775] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/01/2021] [Indexed: 12/13/2022] Open
Abstract
With the discovery of antiretroviral therapy, HIV-1 infection has transitioned into a manageable but chronic illness, which requires lifelong treatment. Nevertheless, complete eradication of the virus has still eluded us. This is partly due to the virus’s ability to remain in a dormant state in tissue reservoirs, ‘hidden’ from the host’s immune system. Also, the high mutation rate of HIV-1 results in escape mutations in response to many therapeutics. Regardless, the development of novel cures for HIV-1 continues to move forward with a range of approaches from immunotherapy to gene editing. However, to evaluate in vivo pathogenesis and the efficacy and safety of therapeutic approaches, a suitable animal model is necessary. To this end, the humanized mouse was developed by McCune in 1988 and has continued to be improved on over the past 30 years. Here, we review the variety of humanized mouse models that have been utilized through the years and describe their specific contribution in translating HIV-1 cure strategies to the clinic.
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Affiliation(s)
- Shawn Abeynaike
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States.,The Skaggs Graduate Program in Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA, United States
| | - Silke Paust
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States.,The Skaggs Graduate Program in Chemical and Biological Sciences, The Scripps Research Institute, La Jolla, CA, United States
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7
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Gillgrass A, Wessels JM, Yang JX, Kaushic C. Advances in Humanized Mouse Models to Improve Understanding of HIV-1 Pathogenesis and Immune Responses. Front Immunol 2021; 11:617516. [PMID: 33746940 PMCID: PMC7973037 DOI: 10.3389/fimmu.2020.617516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/30/2020] [Indexed: 12/15/2022] Open
Abstract
Although antiretroviral therapy has transformed human immunodeficiency virus-type 1 (HIV-1) from a deadly infection into a chronic disease, it does not clear the viral reservoir, leaving HIV-1 as an uncurable infection. Currently, 1.2 million new HIV-1 infections occur globally each year, with little decrease over many years. Therefore, additional research is required to advance the current state of HIV management, find potential therapeutic strategies, and further understand the mechanisms of HIV pathogenesis and prevention strategies. Non-human primates (NHP) have been used extensively in HIV research and have provided critical advances within the field, but there are several issues that limit their use. Humanized mouse (Hu-mouse) models, or immunodeficient mice engrafted with human immune cells and/or tissues, provide a cost-effective and practical approach to create models for HIV research. Hu-mice closely parallel multiple aspects of human HIV infection and disease progression. Here, we highlight how innovations in Hu-mouse models have advanced HIV-1 research in the past decade. We discuss the effect of different background strains of mice, of modifications on the reconstitution of the immune cells, and the pros and cons of different human cells and/or tissue engraftment methods, on the ability to examine HIV-1 infection and immune response. Finally, we consider the newest advances in the Hu-mouse models and their potential to advance research in emerging areas of mucosal infections, understand the role of microbiota and the complex issues in HIV-TB co-infection. These innovations in Hu-mouse models hold the potential to significantly enhance mechanistic research to develop novel strategies for HIV prevention and therapeutics.
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Affiliation(s)
- Amy Gillgrass
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Jocelyn M. Wessels
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada
| | - Jack X. Yang
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
| | - Charu Kaushic
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, ON, Canada
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8
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Akkina R, Barber DL, Bility MT, Bissig KD, Burwitz BJ, Eichelberg K, Endsley JJ, Garcia JV, Hafner R, Karakousis PC, Korba BE, Koshy R, Lambros C, Menne S, Nuermberger EL, Ploss A, Podell BK, Poluektova LY, Sanders-Beer BE, Subbian S, Wahl A. Small Animal Models for Human Immunodeficiency Virus (HIV), Hepatitis B, and Tuberculosis: Proceedings of an NIAID Workshop. Curr HIV Res 2020; 18:19-28. [PMID: 31870268 PMCID: PMC7403688 DOI: 10.2174/1570162x18666191223114019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 11/27/2019] [Accepted: 12/11/2019] [Indexed: 12/21/2022]
Abstract
The main advantage of animal models of infectious diseases over in vitro studies is the gain in the understanding of the complex dynamics between the immune system and the pathogen. While small animal models have practical advantages over large animal models, it is crucial to be aware of their limitations. Although the small animal model at least needs to be susceptible to the pathogen under study to obtain meaningful data, key elements of pathogenesis should also be reflected when compared to humans. Well-designed small animal models for HIV, hepatitis viruses and tuberculosis require, additionally, a thorough understanding of the similarities and differences in the immune responses between humans and small animals and should incorporate that knowledge into the goals of the study. To discuss these considerations, the NIAID hosted a workshop on 'Small Animal Models for HIV, Hepatitis B, and Tuberculosis' on May 30, 2019. Highlights of the workshop are outlined below.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Brigitte E. Sanders-Beer
- Address correspondence to this author at the Division of AIDS, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 5601 Fishers Lane, Bethesda, MD 20892-9830, USA; Tel: (240) 627-3209; E-mail:
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9
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Ladinsky MS, Khamaikawin W, Jung Y, Lin S, Lam J, An DS, Bjorkman PJ, Kieffer C. Mechanisms of virus dissemination in bone marrow of HIV-1-infected humanized BLT mice. eLife 2019; 8:46916. [PMID: 31657719 PMCID: PMC6839903 DOI: 10.7554/elife.46916] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 10/27/2019] [Indexed: 02/06/2023] Open
Abstract
Immune progenitor cells differentiate in bone marrow (BM) and then migrate to tissues. HIV-1 infects multiple BM cell types, but virus dissemination within BM has been poorly understood. We used light microscopy and electron tomography to elucidate mechanisms of HIV-1 dissemination within BM of HIV-1–infected BM/liver/thymus (BLT) mice. Tissue clearing combined with confocal and light sheet fluorescence microscopy revealed distinct populations of HIV-1 p24-producing cells in BM early after infection, and quantification of these populations identified macrophages as the principal subset of virus-producing cells in BM over time. Electron tomography demonstrated three modes of HIV-1 dissemination in BM: (i) semi-synchronous budding from T-cell and macrophage membranes, (ii) mature virus association with virus-producing T-cell uropods contacting putative target cells, and (iii) macrophages engulfing HIV-1–producing T-cells and producing virus within enclosed intracellular compartments that fused to invaginations with access to the extracellular space. These results illustrate mechanisms by which the specialized environment of the BM can promote virus spread locally and to distant lymphoid tissues.
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Affiliation(s)
- Mark S Ladinsky
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Wannisa Khamaikawin
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Yujin Jung
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Samantha Lin
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Jennifer Lam
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Dong Sung An
- School of Nursing, UCLA AIDS Institute, University of California, Los Angeles, Los Angeles, United States
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
| | - Collin Kieffer
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
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10
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Beymer MR, Holloway IW, Pulsipher C, Landovitz RJ. Current and Future PrEP Medications and Modalities: On-demand, Injectables, and Topicals. Curr HIV/AIDS Rep 2019; 16:349-358. [PMID: 31222499 PMCID: PMC6719717 DOI: 10.1007/s11904-019-00450-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE OF REVIEW Pre-exposure prophylaxis (PrEP) is a potent HIV prevention strategy, but uptake of daily oral PrEP remains low. This review covers PrEP agents currently available and agents and modalities under investigation. RECENT FINDINGS Injectable ARV preparations have high acceptability among users but are likely to require adherence to 8-week interval injections. Topical microbicide gels and vaginal rings have underperformed by intention-to-treat analyses in efficacy studies, at least in large part due to challenges with adherence and/or sustained use. However, daily oral TDF-FTC also underperformed in randomized, placebo-controlled trials compared to expectations and subsequent real-world pragmatic use. On-demand (2-1-1 dosing strategy for MSM) and injectable PrEP appear to be acceptable among participants in clinical trials. These modalities are particularly compelling alternatives for individuals who either do not want to take a daily medication (both on-demand and injectable) and/or want to take PrEP without a long commitment (on-demand). Emerging modalities such as vaginal films, microneedles, and subdermal implants have numerous advantages but are still in early stages of development.
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Affiliation(s)
- Matthew R Beymer
- Department of Health and Mental Health Services, Los Angeles LGBT Center, McDonald/Wright Building, 1625 N Schrader Blvd, Room 114-E, Los Angeles, CA, 90028, USA.
| | - Ian W Holloway
- Department of Social Welfare, Luskin School of Public Affairs, University of California, Los Angeles, 337 Charles E Young Drive East, Los Angeles, CA, 90095, USA
| | | | - Raphael J Landovitz
- David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Avenue, Los Angeles, CA, 90095, USA
- UCLA Center for Clinical AIDS Research & Education (CARE), 11075 Santa Monica Blvd, Suite 100, Los Angeles, CA, 90024, USA
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11
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Cheng L, Ma J, Li G, Su L. Humanized Mice Engrafted With Human HSC Only or HSC and Thymus Support Comparable HIV-1 Replication, Immunopathology, and Responses to ART and Immune Therapy. Front Immunol 2018; 9:817. [PMID: 29725337 PMCID: PMC5916969 DOI: 10.3389/fimmu.2018.00817] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 04/04/2018] [Indexed: 12/28/2022] Open
Abstract
Immunodeficient mice reconstituted with human immune tissues and cells (humanized mice) are relevant and robust models for the study of HIV-1 infection, immunopathogenesis, and therapy. In this study, we performed a comprehensive comparison of human immune reconstitution and HIV-1 infection, immunopathogenesis and therapy between immunodeficient NOD/Rag2-/-/γc-/- (NRG) mice transplanted with human HSCs (NRG-hu HSC) and mice transplanted with HSCs and thymus fragments (NRG-hu Thy/HSC) from the same donors. We found that similar human lymphoid and myeloid lineages were reconstituted in NRG-hu HSC and NRG-hu Thy/HSC mice, with human T cells more predominantly reconstituted in NRG-hu Thy/HSC mice, while NRG-hu HSC mice supported more human B cells and myeloid cells reconstitution. HIV-1 replicated similarly and induced similar T cell depletion, immune activation, and dysfunction in NRG-hu HSC and NRG-hu Thy/HSC mice. Moreover, combined antiretroviral therapy (cART) inhibited HIV-1 replication efficiently with similar persistent HIV-1 reservoirs in both models. Finally, we found that blocking type-I interferon signaling under cART treatment transiently activated HIV-1 reservoirs, enhanced T cell recovery and reduced HIV-1 reservoirs in both HIV-1 infected NRG-hu HSC and NRG-hu Thy/HSC mice. In summary, we report that NRG-hu Thy/HSC and NRG-hu HSC mice support similar HIV-1 infection and similar HIV-1 immunopathology; and HIV-1 replication responds similarly to cART and IFNAR blockade therapies. The NRG-hu HSC mouse model reconstituted with human HSC only is sufficient for the study of HIV-1 infection, pathogenesis, and therapy.
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Affiliation(s)
- Liang Cheng
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jianping Ma
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Guangming Li
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Lishan Su
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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12
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Gallay PA, Chatterji U, Kirchhoff A, Gandarilla A, Pyles RB, Baum MM, Moss JA. Protection Efficacy of C5A Against Vaginal and Rectal HIV Challenges in Humanized Mice. Open Virol J 2018. [PMID: 29541273 PMCID: PMC5842390 DOI: 10.2174/1874357901812010001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Introduction: In the absence of a vaccine, there is an urgent need for the identification of effective agents that prevent HIV transmission in uninfected individuals. Non-vaccine Biomedical Prevention (nBP) methods, such as topical or systemic pre-exposure prophylaxis (PrEP), are promising strategies to slow down the spread of AIDS. Methods: In this study, we investigated the microbicidal efficacy of the viral membrane-disrupting amphipathic SWLRDIWDWICEVLSDFK peptide called C5A. We chose the bone marrow/liver/thymus (BLT) humanized mouse model as vaginal and rectal HIV transmission models. Results: We found that the topical administration of C5A offers complete protection against vaginal and rectal HIV challenges in humanized mice. After demonstrating that C5A blocks genital HIV transmission in humanized mice, we examined the molecular requirements for its microbicidal property. We found that the removal of four amino acids on either end of C5A does not diminish its microbicidal efficacy. However, the removal of four amino acids at both the ends, abolishes its capacity to prevent vaginal or rectal HIV transmission, suggesting that the length of the peptide is a critical parameter for the microbicidal activity of C5A. Moreover, we demonstrated that the amphipathicity of the helical peptide as well as its hydrophobic surface represents key factors for the microbicidal activity of C5A in humanized mice. Conclusion: With its noncellular cytotoxic activity, its property of neutralizing both HSV and HIV, and its unique mechanism of action that disrupts the stability of the viral membrane, C5A represents an attractive multipurpose microbicidal candidate to be combined with other anti-HIV agents including antiretrovirals.
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Affiliation(s)
- Philippe A Gallay
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California 92037, USA
| | - Udayan Chatterji
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California 92037, USA
| | - Aaron Kirchhoff
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California 92037, USA
| | - Angel Gandarilla
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California 92037, USA
| | - Richard B Pyles
- Department of Pediatrics, University of Texas Medical Branch; Galveston, Texas 77555-0436, USA
| | - Marc M Baum
- Department of Chemistry, Oak Crest Institute of Science; Monrovia, California 91107. USA
| | - John A Moss
- Department of Chemistry, Oak Crest Institute of Science; Monrovia, California 91107. USA
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13
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Whitney JB, Brad Jones R. In Vitro and In Vivo Models of HIV Latency. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1075:241-263. [DOI: 10.1007/978-981-13-0484-2_10] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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14
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Gallay PA, Chatterji U, Kirchhoff A, Gandarilla A, Gunawardana M, Pyles RB, Marzinke MA, Moss JA, Baum MM. Prevention of vaginal and rectal HIV transmission by antiretroviral combinations in humanized mice. PLoS One 2017; 12:e0184303. [PMID: 28880948 PMCID: PMC5589224 DOI: 10.1371/journal.pone.0184303] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 08/21/2017] [Indexed: 12/24/2022] Open
Abstract
With more than 7,000 new HIV infections daily worldwide, there is an urgent need for non-vaccine biomedical prevention (nBP) strategies that are safe, effective, and acceptable. Clinical trials have demonstrated that pre-exposure prophylaxis (PrEP) with antiretrovirals (ARVs) can be effective at preventing HIV infection. In contrast, other trials using the same ARVs failed to show consistent efficacy. Topical (vaginal and rectal) dosing is a promising regimen for HIV PrEP as it leads to low systematic drug exposure. A series of titration studies were carried out in bone marrow/liver/thymus (BLT) mice aimed at determining the adequate drug concentrations applied vaginally or rectally that offer protection against rectal or vaginal HIV challenge. The dose-response relationship of these agents was measured and showed that topical tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) can offer 100% protection against rectal or vaginal HIV challenges. From the challenge data, EC50 values of 4.6 μM for TDF and 0.6 μM for FTC for HIV vaginal administration and 6.1 μM TDF and 0.18 μM for FTC for rectal administration were obtained. These findings suggest that the BLT mouse model is highly suitable for studying the dose-response relationship in single and combination ARV studies of vaginal or rectal HIV exposure. Application of this sensitive HIV infection model to more complex binary and ternary ARV combinations, particularly where agents have different mechanisms of action, should allow selection of optimal ARV combinations to be advanced into pre-clinical and clinical development as nBP products.
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Affiliation(s)
- Philippe A. Gallay
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California, United States of America
| | - Udayan Chatterji
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California, United States of America
| | - Aaron Kirchhoff
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California, United States of America
| | - Angel Gandarilla
- Department of Immunology & Microbiology, The Scripps Research Institute; La Jolla, California, United States of America
| | - Manjula Gunawardana
- Department of Chemistry, Oak Crest Institute of Science; Monrovia, California, United States of America
| | - Richard B. Pyles
- Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Mark A. Marzinke
- Department of Medicine, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Pathology, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - John A. Moss
- Department of Chemistry, Oak Crest Institute of Science; Monrovia, California, United States of America
| | - Marc M. Baum
- Department of Chemistry, Oak Crest Institute of Science; Monrovia, California, United States of America
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15
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Abstract
HIV has a very limited species tropism that prevents the use of most conventional small animal models for AIDS research. The in vivo analysis of HIV/AIDS has benefited extensively from novel chimeric animal models that accurately recapitulate key aspects of the human condition. Specifically, immunodeficient mice that are systemically repopulated with human hematolymphoid cells offer a viable alternative for the study of a multitude of highly relevant aspects of HIV replication, pathogenesis, therapy, transmission, prevention, and eradication. This article summarizes some of the multiple contributions that humanized mouse models of HIV infection have made to the field of AIDS research. These models have proven to be highly informative and hold great potential for accelerating multiple aspects of HIV research in the future.
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16
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Kovarova M, Swanson MD, Sanchez RI, Baker CE, Steve J, Spagnuolo RA, Howell BJ, Hazuda DJ, Garcia JV. A long-acting formulation of the integrase inhibitor raltegravir protects humanized BLT mice from repeated high-dose vaginal HIV challenges. J Antimicrob Chemother 2016; 71:1586-96. [PMID: 27002074 PMCID: PMC4867102 DOI: 10.1093/jac/dkw042] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 01/11/2016] [Accepted: 01/29/2016] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Pre-exposure prophylaxis (PrEP) using antiretroviral drugs (ARVs) has been shown to reduce HIV transmission in people at high risk of HIV infection. Adherence to PrEP strongly correlates with the level of HIV protection. Long-acting injectable ARVs provide sustained systemic drug exposures over many weeks and can improve adherence due to infrequent parenteral administration. Here, we evaluated a new long-acting formulation of raltegravir for prevention of vaginal HIV transmission. METHODS Long-acting raltegravir was administered subcutaneously to BALB/c, NSG (NOD-scid-gamma) and humanized BLT (bone marrow-liver-thymus) mice and rhesus macaques. Raltegravir concentration in peripheral blood and tissue was analysed. Suppression of HIV replication was assessed in infected BLT mice. Two high-dose HIV vaginal challenges were used to evaluate protection from HIV transmission in BLT mice. RESULTS Two weeks after a single subcutaneous injection of long-acting raltegravir in BLT mice (7.5 mg) and rhesus macaques (160 mg), the plasma concentration of raltegravir was comparable to 400 mg orally, twice daily in humans. Serum collected from mice 3 weeks post-administration of long-acting raltegravir efficiently blocked HIV infection of TZM-bl indicator cells in vitro. Administration of long-acting raltegravir suppressed viral RNA in plasma and cervico-vaginal fluids of infected BLT mice, demonstrating penetration of active raltegravir into the female reproductive tract. Using transmitted/founder HIV we observed that BLT mice administered a single subcutaneous dose of long-acting raltegravir were protected from two high-dose HIV vaginal challenges 1 week and 4 weeks after drug administration. CONCLUSIONS These preclinical results demonstrated the efficacy of long-acting raltegravir in preventing vaginal HIV transmission.
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Affiliation(s)
- Martina Kovarova
- Division of Infectious Diseases, Center for AIDS Research, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
| | - Michael D Swanson
- Division of Infectious Diseases, Center for AIDS Research, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
| | - Rosa I Sanchez
- Merck Research Laboratories, Merck & Co., Inc., West Point, PA 19486, USA
| | - Caroline E Baker
- Division of Infectious Diseases, Center for AIDS Research, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
| | - Justin Steve
- Merck Research Laboratories, Merck & Co., Inc., West Point, PA 19486, USA
| | - Rae Ann Spagnuolo
- Division of Infectious Diseases, Center for AIDS Research, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
| | - Bonnie J Howell
- Merck Research Laboratories, Merck & Co., Inc., West Point, PA 19486, USA
| | - Daria J Hazuda
- Merck Research Laboratories, Merck & Co., Inc., West Point, PA 19486, USA
| | - J Victor Garcia
- Division of Infectious Diseases, Center for AIDS Research, School of Medicine, University of North Carolina at Chapel Hill, NC, USA
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17
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Roan NR, Münch J. Improving preclinical models of HIV microbicide efficacy. Trends Microbiol 2016; 23:445-7. [PMID: 26250616 DOI: 10.1016/j.tim.2015.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/18/2015] [Accepted: 05/01/2015] [Indexed: 01/05/2023]
Abstract
Despite potent in vitro efficacy, most topical microbicides fail to effectively prevent HIV transmission. One reason for clinical failure may be that current microbicide testing does not reflect the environment encountered during sexual virus transmission. We discuss how preclinical microbicide development could be improved by more closely mimicking real-life conditions.
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Affiliation(s)
- Nadia R Roan
- Department of Urology, University of California, San Francisco, San Francisco, CA 94158, USA; Gladstone Institute of Virology and Immunology, San Francisco, CA 94158, USA
| | - Jan Münch
- Institute of Molecular Virology, UPEP, Ulm University Medical Centre, Meyerhofstrasse 1, 89081 Ulm, Germany; Ulm Peptide Pharmaceuticals, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
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18
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Abstract
Human immunodeficiency virus type 1 (HIV-1) gives rise to a chronic infection that progressively depletes CD4(+) T lymphocytes. CD4(+) T lymphocytes play a central coordinating role in adaptive cellular and humoral immune responses, and to do so they migrate and interact within lymphoid compartments and at effector sites to mount immune responses. While cell-free virus serves as an excellent prognostic indicator for patient survival, interactions of infected T cells or virus-scavenging immune cells with uninfected T cells can greatly enhance viral spread. HIV can induce interactions between infected and uninfected T cells that are triggered by cell surface expression of viral Env, which serves as a cell adhesion molecule that interacts with CD4 on the target cell, before it acts as the viral membrane fusion protein. These interactions are called virological synapses and promote replication in the face of selective pressure of humoral immune responses and antiretroviral therapy. Other infection-enhancing cell-cell interactions occur between virus-concentrating antigen-presenting cells and recipient T cells, called infectious synapses. The exact roles that these cell-cell interactions play in each stage of infection, from viral acquisition, systemic dissemination, to chronic persistence are still being determined. Infection-promoting immune cell interactions are likely to contribute to viral persistence and enhance the ability of HIV-1 to evade adaptive immune responses.
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Affiliation(s)
- K M Law
- Immunology Institute Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - N Satija
- Immunology Institute Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - A M Esposito
- Immunology Institute Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - B K Chen
- Immunology Institute Icahn School of Medicine at Mount Sinai, New York, NY, United States.
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19
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Abstract
PURPOSE OF REVIEW Long-acting injectable antiretroviral (ARV) formulations are being developed for the treatment and prevention of HIV infection. The purpose of this review is to summarize recent preclinical and clinical data on TMC278 (rilpivirine), a nonnucleoside reverse transcriptase inhibitor (NNRTI), that is being developed for both a treatment and prevention indication. RECENT FINDINGS Long-acting rilpivirine has demonstrated efficacy in preventing HIV acquisition in a humanized mouse model and has been found to be well tolerated and acceptable in several Phase I clinical trials. Pharmacokinetic data from Phase I studies suggest that 1200 mg of long-acting rilpivirine administered every 8 weeks would be associated with plasma and tissue levels of rilpivirine anticipated to be necessary for preventing HIV infection. This regimen is being evaluated in the HPTN-076 Phase II expanded safety study that will enroll women in South Africa, Zimbabwe, and the USA. The HPTN-076 study requires a 4-week run in with oral rilpivirine (25 mg capsules) before receiving 1200 mg of rilpivirine. It is not yet certain whether oral dosing will remain a prerequisite in future trials or post licensure. SUMMARY Long-acting rilpivirine shows promise as a candidate agent for HIV prevention. Preclinical efficacy has been demonstrated in a murine model. Phase I studies have shown good safety and efficacy, but breakthrough infection and resistance have been documented with lower doses of long-acting rilpivirine. Phase II development for a prevention indication is ongoing.
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20
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Veselinovic M, Charlins P, Akkina R. Modeling HIV-1 Mucosal Transmission and Prevention in Humanized Mice. Methods Mol Biol 2016; 1354:203-20. [PMID: 26714714 DOI: 10.1007/978-1-4939-3046-3_14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The new generation humanized mice (hu-mice) that permit continuous de novo generation of human hematopoietic cells have led to novel strategies in studying HIV-1 pathogenesis, prevention and therapies. HIV-1 infection of hu-mice results in chronic viremia and CD4+ T cell loss, thus mimicking key aspects of the disease progression. In addition, the new generation hu-mice are permissive for HIV-1 sexual transmission by vaginal and rectal routes thus allowing in vivo efficacy testing of new anti-HIV-1 drugs for prevention. Two leading models are currently being used, namely the hu-HSC mice and the BLT mice. Here we describe the methodology for generating both hu-HSC and BLT mice and their use in the study of HIV-1 transmission and prevention of infection by topical and oral administration of anti-retroviral drugs. Practical aspects of the methodologies are emphasized.
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Affiliation(s)
- Milena Veselinovic
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO, 80523, USA
| | - Paige Charlins
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO, 80523, USA
| | - Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO, 80523, USA.
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21
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Abstract
Antiretroviral preexposure prophylaxis has huge potential for reducing the rates of new HIV infections in at risk populations. Oral and vaginal antiretroviral formulations have been evaluated in multiple Phase IIB and Phase III effectiveness trials and there is clear evidence that these products work when used. The converse is also true; antiretrovirals do not work when they are not used and unfortunately adherence is a problem for both HIV treatment and prevention. As a consequence, long-acting injectable and implantable antiretroviral formulations are being developed for the treatment and prevention of HIV infection. It is hoped they will reduce the burden of product adherence associated with the use of oral and topical products and improve clinical outcomes associated with their use. The purpose of this review is to summarize recent preclinical and clinical research in this area of HIV prevention.
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Affiliation(s)
- Ian McGowan
- Magee-Womens Research Institute, Division of Gastroenterology, Hepatology, & Nutrition, University of Pittsburgh School of Medicine, 204 Craft Ave, Room B621, Pittsburgh, PA 15213, USA
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22
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Role of Semen on Vaginal HIV-1 Transmission and Maraviroc Protection. Antimicrob Agents Chemother 2015; 59:7847-51. [PMID: 26392489 DOI: 10.1128/aac.01496-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 09/13/2015] [Indexed: 11/20/2022] Open
Abstract
We used bone marrow/liver/thymus (BLT) humanized mice to establish the effect of semen on vaginal HIV infection and on the efficacy of topically applied maraviroc. Our results demonstrate that vaginal transmission of cell-free HIV occurs efficiently in the presence of semen and that topically applied maraviroc efficiently prevents HIV transmission in the presence of semen. We also show that semen has no significant effect on the transmission of transmitted/founder viruses or cell-associated viruses.
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23
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Fernández-Romero JA, Teleshova N, Zydowsky TM, Robbiani M. Preclinical assessments of vaginal microbicide candidate safety and efficacy. Adv Drug Deliv Rev 2015; 92:27-38. [PMID: 25543007 DOI: 10.1016/j.addr.2014.12.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/04/2014] [Accepted: 12/18/2014] [Indexed: 11/15/2022]
Abstract
Sexually transmitted infections like HIV, HPV, and HSV-2, as well as unplanned pregnancy, take a huge toll on women worldwide. Woman-initiated multipurpose prevention technologies that contain antiviral/antibacterial drugs (microbicides) and a contraceptive to simultaneously target sexually transmitted infections and unplanned pregnancy are being developed to reduce these burdens. This review will consider products that are applied topically to the vagina. Rectally administered topical microbicides in development for receptive anal intercourse are outside the scope of this review. Microbicide and microbicide/contraceptive candidates must be rigorously evaluated in preclinical models of safety and efficacy to ensure that only candidates with favorable risk benefit ratios are advanced into human clinical trials. This review describes the comprehensive set of in vitro, ex vivo, and in vivo models used to evaluate the preclinical safety and antiviral efficacy of microbicide and microbicide/contraceptive candidates.
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MESH Headings
- Administration, Intravaginal
- Animals
- Antiviral Agents/administration & dosage
- Antiviral Agents/adverse effects
- Antiviral Agents/pharmacokinetics
- Antiviral Agents/therapeutic use
- Contraceptive Agents, Female/administration & dosage
- Contraceptive Agents, Female/adverse effects
- Contraceptive Agents, Female/pharmacokinetics
- Contraceptive Agents, Female/therapeutic use
- Drug Evaluation, Preclinical/methods
- Drug Evaluation, Preclinical/standards
- Female
- HIV Infections/prevention & control
- Haplorhini
- Herpes Genitalis/prevention & control
- Humans
- Mice
- Models, Biological
- Papillomavirus Infections/prevention & control
- Pregnancy
- Pregnancy, Unplanned
- Sexually Transmitted Diseases, Viral/prevention & control
- Vagina/physiology
- Vaginal Absorption
- Vaginal Creams, Foams, and Jellies/pharmacokinetics
- Vaginal Creams, Foams, and Jellies/therapeutic use
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Affiliation(s)
| | - Natalia Teleshova
- Center for Biomedical Research, Population Council, New York, NY, USA
| | - Thomas M Zydowsky
- Center for Biomedical Research, Population Council, New York, NY, USA
| | - Melissa Robbiani
- Center for Biomedical Research, Population Council, New York, NY, USA
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24
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Kovarova M, Council OD, Date AA, Long JM, Nochii T, Belshan M, Shibata A, Vincent H, Baker CE, Thayer WO, Kraus G, Lachaud-Durand S, Williams P, Destache CJ, Garcia JV. Nanoformulations of Rilpivirine for Topical Pericoital and Systemic Coitus-Independent Administration Efficiently Prevent HIV Transmission. PLoS Pathog 2015; 11:e1005075. [PMID: 26271040 PMCID: PMC4536200 DOI: 10.1371/journal.ppat.1005075] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/08/2015] [Indexed: 01/11/2023] Open
Abstract
Vaginal HIV transmission accounts for the majority of new infections worldwide. Currently, multiple efforts to prevent HIV transmission are based on pre-exposure prophylaxis with various antiretroviral drugs. Here, we describe two novel nanoformulations of the reverse transcriptase inhibitor rilpivirine for pericoital and coitus-independent HIV prevention. Topically applied rilpivirine, encapsulated in PLGA nanoparticles, was delivered in a thermosensitive gel, which becomes solid at body temperature. PLGA nanoparticles with encapsulated rilpivirine coated the reproductive tract and offered significant protection to BLT humanized mice from a vaginal high-dose HIV-1 challenge. A different nanosuspension of crystalline rilpivirine (RPV LA), administered intramuscularly, protected BLT mice from a single vaginal high-dose HIV-1 challenge one week after drug administration. Using transmitted/founder viruses, which were previously shown to establish de novo infection in humans, we demonstrated that RPV LA offers significant protection from two consecutive high-dose HIV-1 challenges one and four weeks after drug administration. In this experiment, we also showed that, in certain cases, even in the presence of drug, HIV infection could occur without overt or detectable systemic replication until levels of drug were reduced. We also showed that infection in the presence of drug can result in acquisition of multiple viruses after subsequent exposures. These observations have important implications for the implementation of long-acting antiretroviral formulations for HIV prevention. They provide first evidence that occult infections can occur, despite the presence of sustained levels of antiretroviral drugs. Together, our results demonstrate that topically- or systemically administered rilpivirine offers significant coitus-dependent or coitus-independent protection from HIV infection. When taken consistently, PrEP has been shown to reduce the risk of HIV infection by up to 92% in people who are at high risk. However, PrEP is much less effective if it is not taken consistently. To improve adherence to the drug regimen, several new drug delivery systems, that include novel gel formulations and long-acting delivery systems, are being evaluated. In this manuscript, we used BLT humanized mice, an in vivo model of vaginal HIV transmission, to evaluate two novel delivery systems for HIV prevention. In the first approach, we combined the highly efficient encapsulation of antiretroviral drugs into nanoparticles with a thermosensitive gel that remains liquid at room temperature and solidifies at body temperature. Our results showed that this delivery system provided significant protection from HIV vaginal infection. In a second approach, we evaluated a long-acting nanoparticle formulation for coitus-independent protection from HIV acquisition. Our results showed that a single injection of the long-acting antiviral drug also resulted in reduced HIV infection. However, protection was not complete and transmission was concealed by a significant delay in the onset of plasma viremia that could result in superinfection by two different viruses administered up to four weeks apart.
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Affiliation(s)
- Martina Kovarova
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
- * E-mail: (MK); (JVG)
| | - Olivia D. Council
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Abhijit A. Date
- Department of Pharmacy Practice, Creighton University School of Pharmacy and Health Professions, Omaha, Nebraska, United States of America
| | - Julie M. Long
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Tomonori Nochii
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Michael Belshan
- Department of Pharmacy Practice, Creighton University School of Pharmacy and Health Professions, Omaha, Nebraska, United States of America
| | - Annemarie Shibata
- Department of Pharmacy Practice, Creighton University School of Pharmacy and Health Professions, Omaha, Nebraska, United States of America
| | - Heather Vincent
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Caroline E. Baker
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | - William O. Thayer
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
| | | | | | | | - Christopher J. Destache
- Department of Pharmacy Practice, Creighton University School of Pharmacy and Health Professions, Omaha, Nebraska, United States of America
| | - J. Victor Garcia
- Division of Infectious Diseases, Center for AIDS Research, University of North Carolina at Chapel Hill, School of Medicine, Chapel Hill, North Carolina, United States of America
- * E-mail: (MK); (JVG)
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25
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Watkins RL, Foster JL, Garcia JV. In vivo analysis of Nef's role in HIV-1 replication, systemic T cell activation and CD4(+) T cell loss. Retrovirology 2015; 12:61. [PMID: 26169178 PMCID: PMC4501112 DOI: 10.1186/s12977-015-0187-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 06/29/2015] [Indexed: 11/21/2022] Open
Abstract
Background Nef is a multifunctional HIV-1 protein critical for progression to AIDS. Humans infected with nef(−) HIV-1 have greatly delayed or no disease consequences. We have contrasted nef(−) and nef(+) infection of BLT humanized mice to better characterize Nef’s pathogenic effects. Results Mice were inoculated with CCR5-tropic HIV-1JRCSF (JRCSF) or JRCSF with an irreversibly inactivated nef (JRCSFNefdd). In peripheral blood (PB), JRCSF exhibited high levels of viral RNA (peak viral loads of 4.71 × 106 ± 1.23 × 106 copies/ml) and a progressive, 75% loss of CD4+ T cells over 17 weeks. Similar losses were observed in CD4+ T cells from bone marrow, spleen, lymph node, lung and liver but thymocytes were not significantly decreased. JRCSFNefdd also had high peak viral loads (2.31 × 106 ± 1.67 × 106) but induced no loss of PB CD4+ T cells. In organs, JRCSFNefdd produced small, but significant, reductions in CD4+ T cell levels and did not affect the level of thymocytes. Uninfected mice have low levels of HLA-DR+CD38+CD8+ T cells in blood (1–2%). Six weeks post inoculation, JRCSF infection resulted in significantly elevated levels of activated CD8+ T cells (6.37 ± 1.07%). T cell activation coincided with PB CD4+ T cell loss which suggests a common Nef-dependent mechanism. At 12 weeks, in JRCSF infected animals PB T cell activation sharply increased to 19.7 ± 2.9% then subsided to 5.4 ± 1.4% at 14 weeks. HLA-DR+CD38+CD8+ T cell levels in JRCSFNefdd infected mice did not rise above 1–2% despite sustained high levels of viremia. Interestingly, we also noted that in mice engrafted with human tissue expressing a putative protective HLA-B allele (B42:01), JRCSFNefdd exhibited a substantial (200-fold) reduced viral load compared to JRCSF. Conclusions Nef expression was necessary for both systemic T cell activation and substantial CD4+ T cell loss from blood and tissues. JRCSFNefdd infection did not activate CD8+ T cells or reduce the level of CD4+ T cells in blood but did result in a small Nef-independent decrease in CD4+ T cells in organs. These observations strongly support the conclusion that viral pathogenicity is mostly driven by Nef. We also observed for the first time substantial host-specific suppression of HIV-1 replication in a small animal infection model. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0187-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard L Watkins
- Division of Infectious Diseases, UNC Center for AIDS Research, Genetic Medicine, University of North Carolina, Campus Box 7042, Chapel Hill, NC, 27599-7042, USA.
| | - John L Foster
- Division of Infectious Diseases, UNC Center for AIDS Research, Genetic Medicine, University of North Carolina, Campus Box 7042, Chapel Hill, NC, 27599-7042, USA.
| | - J Victor Garcia
- Division of Infectious Diseases, UNC Center for AIDS Research, Genetic Medicine, University of North Carolina, Campus Box 7042, Chapel Hill, NC, 27599-7042, USA.
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The Vaginal Acquisition and Dissemination of HIV-1 Infection in a Novel Transgenic Mouse Model Is Facilitated by Coinfection with Herpes Simplex Virus 2 and Is Inhibited by Microbicide Treatment. J Virol 2015; 89:9559-70. [PMID: 26157126 DOI: 10.1128/jvi.01326-15] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 07/02/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Epidemiological studies have demonstrated that herpes simplex virus 2 (HSV-2) infection significantly increases the risk of HIV-1 acquisition, thereby contributing to the expanding HIV-1 epidemic. To investigate whether HSV-2 infection directly facilitates mucosal HIV-1 acquisition, we used our transgenic hCD4/R5/cT1 mouse model which circumvents major entry and transcription blocks preventing murine HIV-1 infection by targeting transgenic expression of human CD4, CCR5, and cyclin T1 genes to CD4(+) T cells and myeloid-committed cells. Productive infection of mucosal leukocytes, predominantly CD4(+) T cells, was detected in all hCD4/R5/cT1 mice intravaginally challenged with an HIV-1 infectious molecular clone, HIV-Du151.2env-NLuc, which expresses an env gene (C.Du151.2) cloned from an acute heterosexually infected woman and a NanoLuc luciferase reporter gene. Lower genital tract HIV-1 infection after HIV-Du151.2env-NLuc intravaginal challenge was increased ~4-fold in hCD4/R5/cT1 mice coinfected with HSV-2. Furthermore, HIV-1 dissemination to draining lymph nodes was detected only in HSV-2-coinfected mice. HSV-2 infection stimulated local infiltration and activation of CD4(+) T cells and dendritic cells, likely contributing to the enhanced HIV-1 infection and dissemination in HSV-2-coinfected mice. We then used this model to demonstrate that a novel gel containing tenofovir disoproxil fumarate (TDF), the more potent prodrug of tenofovir (TFV), but not the TFV microbicide gel utilized in the recent CAPRISA 004, VOICE (Vaginal and Oral Interventions to Control the Epidemic), and FACTS 001 clinical trials, was effective as preexposure prophylaxis (PrEP) to completely prevent vaginal HIV-1 infection in almost half of HSV-2-coinfected mice. These results also support utilization of hCD4/R5/cT1 mice as a highly reproducible immunocompetent preclinical model to evaluate HIV-1 acquisition across the female genital tract. IMPORTANCE Multiple epidemiological studies have reported that genital herpes simplex virus 2 (HSV-2) infection increases the risk of HIV-1 sexual acquisition by severalfold. Understanding the underlying mechanisms by which HSV-2 facilitates HIV-1 infection and optimizing the efficacy of therapies to inhibit HIV-1 infection during HSV-2 coinfection should contribute to reducing HIV-1 transmission. Using our novel transgenic hCD4/R5/cT1 mouse model infectible with HIV-1, we demonstrated that HSV-2 infection enhances vaginal transmission and dissemination of HIV-1 infection while stimulating recruitment and activation of CD4(+) T cells and dendritic cells in the lower genital tract. HIV acquisition by hCD4/R5/cT1 mice vaginally coinfected with HSV-2 could be completely prevented in almost half the mice by preexposure prophylaxis (PrEP) with a novel gel containing tenofovir disoproxil fumarate (TDF), the tenofovir prodrug, but not with the tenofovir microbicide gel utilized in CAPRISA-004, VOICE, and FACTS-001 clinical trials. The hCD4/R5/cT1 mice represent a new preclinical mouse model to evaluate vaginal HIV-1 acquisition.
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Abstract
During the past decade, the development of humanized mouse models and their general applications in biomedical research greatly accelerated the translation of outcomes obtained from basic research into potential diagnostic and therapeutic strategies in clinic. In this chapter, we firstly present an overview on the history and current progress of diverse humanized mouse models and then focus on those equipped with reconstituted human immune system. The update advancement in the establishment of humanized immune system mice and their applications in the studies of the development of human immune system and the pathogenesis of multiple human immune-related diseases are intensively reviewed here, while the shortcoming and perspective of these potent tools are discussed as well. As a valuable bridge across the gap between bench work and clinical trial, progressive humanized mouse models will undoubtedly continue to play an indispensable role in the wide area of biomedical research.
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Moench TR. Cell-associated transmission of HIV type 1 and other lentiviruses in small-animal models. J Infect Dis 2015; 210 Suppl 3:S654-9. [PMID: 25414420 DOI: 10.1093/infdis/jiu368] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Small-animal models of lentivirus transmission have repeatedly demonstrated transmission by cell-associated virus via vaginal, rectal, and oral routes. The earliest experiments were in the cat/feline immunodeficiency virus model, followed a decade later by successful vaginal transmission of cell-associated human immunodeficiency virus (HIV) in mice bearing transplanted human immune cells. After early unsuccessful attempts at cell-associated transmission in nonhuman primates, renewed investigation in diverse primate models has now confirmed the findings from the cat and humanized mouse models. Improvements in humanized mouse models have made them the preferred small-animal models to study HIV mucosal transmission. They provide complementary systems to nonhuman primate models to aid in the elucidation of the many remaining questions on the mechanism of and means to prevent both cell-associated and cell-free HIV transmission across mucosal barriers.
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Li Y, Di Santo JP. Probing Human NK Cell Biology Using Human Immune System (HIS) Mice. Curr Top Microbiol Immunol 2015; 395:191-208. [PMID: 26459320 DOI: 10.1007/82_2015_488] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Our incomplete understanding of the mechanisms that orchestrate human lymphocyte differentiation and condition human immune responses is in part due to the limited access to normal human tissue samples that can inform on these complex processes. In addition, in vitro culture conditions fail to recapitulate the three-dimensional microenvironments that influence cell-cell interactions and impact on immune outcomes. Small animals provide a preclinical model to dissect and probe immunity and over the past decades, development of immunodeficient hosts that can be engrafted with human hematopoietic precursors and mature cells have led to the development of new in vivo models to study human lymphocyte development and function. Natural killer (NK) cells are implicated in the recognition and elimination of pathogen-infected and transformed cells and belong to a family of diverse innate lymphoid cells (ILCs) that provide early immune defense against disease. Here, we summarize the use of humanized mouse models for the study of NK cell and group 1 ILCs and their respective roles in immunity and tissue homeostasis.
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Affiliation(s)
- Yan Li
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, Paris, 75724, France.,Inserm U668, Paris, France
| | - James P Di Santo
- Innate Immunity Unit, Institut Pasteur, 25 rue du Docteur Roux, Paris, 75724, France. .,Inserm U668, Paris, France.
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Fernández Romero JA, Gil PI, Ré V, Robbiani M, Paglini G. [Microbicides for preventing sexually transmitted infections: Current status and strategies for preclinical evaluation of new candidates]. Rev Argent Microbiol 2014; 46:256-68. [PMID: 25444135 DOI: 10.1016/s0325-7541(14)70080-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/26/2014] [Indexed: 01/02/2023] Open
Abstract
Microbicides are a new tool, still under investigation, which could help prevent infection by the human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). Increasing evidence shows that the complexity of sexual transmission of viral pathogens requires the identification of compounds able to block the early events during the cycle of viral infection. In this manuscript we provide a comprehensive review of the different microbicide strategies that have been studied or are currently being considered for STI prevention, particularly emphasizing those having the potential to block HIV infection. The manuscript also reviews the complex process that is required to conduct future clinical studies in humans and concludes with a brief discussion of the strategies that could be part of the immediate future in microbicide research.
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Affiliation(s)
- José A Fernández Romero
- Center for Biomedical Research, Population Council, Nueva York, Nueva York, EE. UU; Instituto de Virología "Dr. J.M. Vanella", Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Pedro I Gil
- Instituto de Virología "Dr. J.M. Vanella", Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Viviana Ré
- Instituto de Virología "Dr. J.M. Vanella", Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Melissa Robbiani
- Center for Biomedical Research, Population Council, Nueva York, Nueva York, EE. UU
| | - Gabriela Paglini
- Instituto de Virología "Dr. J.M. Vanella", Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
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Veselinovic M, Yang KH, LeCureux J, Sykes C, Remling-Mulder L, Kashuba ADM, Akkina R. HIV pre-exposure prophylaxis: mucosal tissue drug distribution of RT inhibitor Tenofovir and entry inhibitor Maraviroc in a humanized mouse model. Virology 2014; 464-465:253-263. [PMID: 25105490 DOI: 10.1016/j.virol.2014.07.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 04/24/2014] [Accepted: 07/08/2014] [Indexed: 12/22/2022]
Abstract
Pre-exposure prophylaxis (PrEP) strategies utilizing anti-retroviral drugs show considerable promise for HIV prevention. However there is insufficient pharmacokinetic (PK) data on drug concentrations required for protection at the relevant mucosal tissues where the infection is initiated. Here we evaluated the utility of a humanized mouse model to derive PK data on two leading drugs, the RT inhibitor Tenofovir (TFV) and CCR5 inhibitor Maraviroc (MVC). Following oral dosing, both the drugs and the intracellular active TFV-diphosphate could be detected in vaginal, rectal and intestinal tissues. The drug exposures (AUC₂₄ h) were found to be higher in vaginal tissue compared to plasma with even higher levels detected in rectal and intestinal tissues. The overall trends of drug concentrations seen in humanized mice reflect those seen in the human thus establishing the utility of this model complementing the present non-human primate (NHP) models for future pre-clinical evaluations of promising HIV PrEP drug candidates.
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Affiliation(s)
- Milena Veselinovic
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Kuo-Hsiung Yang
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Jonathan LeCureux
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Craig Sykes
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA
| | - Leila Remling-Mulder
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Angela D M Kashuba
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, USA; School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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Brehm MA, Wiles MV, Greiner DL, Shultz LD. Generation of improved humanized mouse models for human infectious diseases. J Immunol Methods 2014; 410:3-17. [PMID: 24607601 PMCID: PMC4155027 DOI: 10.1016/j.jim.2014.02.011] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 02/18/2014] [Indexed: 12/26/2022]
Abstract
The study of human-specific infectious agents has been hindered by the lack of optimal small animal models. More recently development of novel strains of immunodeficient mice has begun to provide the opportunity to utilize small animal models for the study of many human-specific infectious agents. The introduction of a targeted mutation in the IL2 receptor common gamma chain gene (IL2rg(null)) in mice already deficient in T and B cells led to a breakthrough in the ability to engraft hematopoietic stem cells, as well as functional human lymphoid cells and tissues, effectively creating human immune systems in immunodeficient mice. These humanized mice are becoming increasingly important as pre-clinical models for the study of human immunodeficiency virus-1 (HIV-1) and other human-specific infectious agents. However, there remain a number of opportunities to further improve humanized mouse models for the study of human-specific infectious agents. This is being done by the implementation of innovative technologies, which collectively will accelerate the development of new models of genetically modified mice, including; i) modifications of the host to reduce innate immunity, which impedes human cell engraftment; ii) genetic modification to provide human-specific growth factors and cytokines required for optimal human cell growth and function; iii) and new cell and tissue engraftment protocols. The development of "next generation" humanized mouse models continues to provide exciting opportunities for the establishment of robust small animal models to study the pathogenesis of human-specific infectious agents, as well as for testing the efficacy of therapeutic agents and experimental vaccines.
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Affiliation(s)
- Michael A Brehm
- The University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, United States.
| | - Michael V Wiles
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, United States.
| | - Dale L Greiner
- The University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, United States.
| | - Leonard D Shultz
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, United States.
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Cottrell ML, Kashuba ADM. Topical microbicides and HIV prevention in the female genital tract. J Clin Pharmacol 2014; 54:603-15. [PMID: 24664786 DOI: 10.1002/jcph.292] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 03/19/2014] [Indexed: 11/05/2022]
Abstract
Worldwide, HIV disproportionately affects women who are often unable to negotiate traditional HIV preventive strategies such as condoms. In the absence of an effective vaccine or cure, chemoprophylaxis may be a valuable self-initiated alternative. Topical microbicides have been investigated as one such option. The first generation topical microbicides were non-specific, broad-spectrum antimicrobial agents, including surfactants, polyanions, and acid buffering gels, that generally exhibited contraceptive properties. After extensive clinical study, none prevented HIV infection, and their development was abandoned. Second generation topical microbicides include agents with selective mechanisms of antiviral activity. Most are currently being used for, or have previously been explored as, drugs for treatment of HIV. The most advanced of these is tenofovir 1% gel: the first topical agent shown to significantly reduce HIV infection by 39% compared to placebo. This review summarizes the evolution of topical microbicides for HIV chemoprophylaxis, highlights important concepts learned, and offers current and future considerations for this area of research.
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Affiliation(s)
- Mackenzie L Cottrell
- University of North Carolina at Chapel Hill, UNC Eshelman School of Pharmacy, Chapel Hill, NC, USA
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Ladinsky MS, Kieffer C, Olson G, Deruaz M, Vrbanac V, Tager AM, Kwon DS, Bjorkman PJ. Electron tomography of HIV-1 infection in gut-associated lymphoid tissue. PLoS Pathog 2014; 10:e1003899. [PMID: 24497830 PMCID: PMC3907528 DOI: 10.1371/journal.ppat.1003899] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 12/09/2013] [Indexed: 02/07/2023] Open
Abstract
Critical aspects of HIV-1 infection occur in mucosal tissues, particularly in the gut, which contains large numbers of HIV-1 target cells that are depleted early in infection. We used electron tomography (ET) to image HIV-1 in gut-associated lymphoid tissue (GALT) of HIV-1-infected humanized mice, the first three-dimensional ultrastructural examination of HIV-1 infection in vivo. Human immune cells were successfully engrafted in the mice, and following infection with HIV-1, human T cells were reduced in GALT. Virions were found by ET at all stages of egress, including budding immature virions and free mature and immature viruses. Immuno-electron microscopy verified the virions were HIV-1 and showed CD4 sequestration in the endoplasmic reticulum of infected cells. Observation of HIV-1 in infected GALT tissue revealed that most HIV-1-infected cells, identified by immunolabeling and/or the presence of budding virions, were localized to intestinal crypts with pools of free virions concentrated in spaces between cells. Fewer infected cells were found in mucosal regions and the lamina propria. The preservation quality of reconstructed tissue volumes allowed details of budding virions, including structures interpreted as host-encoded scission machinery, to be resolved. Although HIV-1 virions released from infected cultured cells have been described as exclusively mature, we found pools of both immature and mature free virions within infected tissue. The pools could be classified as containing either mostly mature or mostly immature particles, and analyses of their proximities to the cell of origin supported a model of semi-synchronous waves of virion release. In addition to HIV-1 transmission by pools of free virus, we found evidence of transmission via virological synapses. Three-dimensional EM imaging of an active infection within tissue revealed important differences between cultured cell and tissue infection models and furthered the ultrastructural understanding of HIV-1 transmission within lymphoid tissue.
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Affiliation(s)
- Mark S. Ladinsky
- Division of Biology & Biological Engineering 114-96, California Institute of Technology, Pasadena, California, United States of America
| | - Collin Kieffer
- Division of Biology & Biological Engineering 114-96, California Institute of Technology, Pasadena, California, United States of America
| | - Gregory Olson
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Maud Deruaz
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Vladimir Vrbanac
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Andrew M. Tager
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, United States of America
| | - Douglas S. Kwon
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Pamela J. Bjorkman
- Division of Biology & Biological Engineering 114-96, California Institute of Technology, Pasadena, California, United States of America
- Howard Hughes Medical Institute, California Institute of Technology, Pasadena, California, United States of America
- * E-mail:
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Denton PW, Long JM, Wietgrefe SW, Sykes C, Spagnuolo RA, Snyder OD, Perkey K, Archin NM, Choudhary SK, Yang K, Hudgens MG, Pastan I, Haase AT, Kashuba AD, Berger EA, Margolis DM, Garcia JV. Targeted cytotoxic therapy kills persisting HIV infected cells during ART. PLoS Pathog 2014; 10:e1003872. [PMID: 24415939 PMCID: PMC3887103 DOI: 10.1371/journal.ppat.1003872] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/22/2013] [Indexed: 11/18/2022] Open
Abstract
Antiretroviral therapy (ART) can reduce HIV levels in plasma to undetectable levels, but rather little is known about the effects of ART outside of the peripheral blood regarding persistent virus production in tissue reservoirs. Understanding the dynamics of ART-induced reductions in viral RNA (vRNA) levels throughout the body is important for the development of strategies to eradicate infectious HIV from patients. Essential to a successful eradication therapy is a component capable of killing persisting HIV infected cells during ART. Therefore, we determined the in vivo efficacy of a targeted cytotoxic therapy to kill infected cells that persist despite long-term ART. For this purpose, we first characterized the impact of ART on HIV RNA levels in multiple organs of bone marrow-liver-thymus (BLT) humanized mice and found that antiretroviral drug penetration and activity was sufficient to reduce, but not eliminate, HIV production in each tissue tested. For targeted cytotoxic killing of these persistent vRNA(+) cells, we treated BLT mice undergoing ART with an HIV-specific immunotoxin. We found that compared to ART alone, this agent profoundly depleted productively infected cells systemically. These results offer proof-of-concept that targeted cytotoxic therapies can be effective components of HIV eradication strategies.
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Affiliation(s)
- Paul W. Denton
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Julie M. Long
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Stephen W. Wietgrefe
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Craig Sykes
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Rae Ann Spagnuolo
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Olivia D. Snyder
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Katherine Perkey
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Nancie M. Archin
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Shailesh K. Choudhary
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Kuo Yang
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Michael G. Hudgens
- Department of Biostatistics, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Ira Pastan
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ashley T. Haase
- Department of Microbiology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Angela D. Kashuba
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Edward A. Berger
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David M. Margolis
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - J. Victor Garcia
- Division of Infectious Diseases, Department of Medicine, UNC Center for AIDS Research, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Abstract
PURPOSE OF REVIEW Early studies have cast doubt on the utility of animal models for predicting success or failure of HIV-prevention strategies, but results of multiple human phase 3 microbicide trials, and interrogations into the discrepancies between human and animal model trials, indicate that animal models were, and are, predictive of safety and efficacy of microbicide candidates. RECENT FINDINGS Recent studies have shown that topically applied vaginal gels, and oral prophylaxis using single or combination antiretrovirals are indeed effective in preventing sexual HIV transmission in humans, and all of these successes were predicted in animal models. Further, prior discrepancies between animal and human results are finally being deciphered as inadequacies in study design in the model, or quite often, noncompliance in human trials, the latter being increasingly recognized as a major problem in human microbicide trials. SUMMARY Successful microbicide studies in humans have validated results in animal models, and several ongoing studies are further investigating questions of tissue distribution, duration of efficacy, and continued safety with repeated application of these, and other promising microbicide candidates in both murine and nonhuman primate models. Now that we finally have positive correlations with prevention strategies and protection from HIV transmission, we can retrospectively validate animal models for their ability to predict these results, and more importantly, prospectively use these models to select and advance even safer, more effective, and importantly, more durable microbicide candidates into human trials.
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Bennett MS, Akkina R. Gene therapy strategies for HIV/AIDS: preclinical modeling in humanized mice. Viruses 2013; 5:3119-41. [PMID: 24351796 PMCID: PMC3967164 DOI: 10.3390/v5123119] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/04/2013] [Accepted: 12/03/2013] [Indexed: 12/28/2022] Open
Abstract
In the absence of an effective vaccine and lack of a complete cure, gene therapy approaches to control HIV infection offer feasible alternatives. Due to the chronic nature of infection, a wide window of opportunity exists to gene modify the HIV susceptible cells that continuously arise from the bone marrow source. To evaluate promising gene therapy approaches that employ various anti-HIV therapeutic molecules, an ideal animal model is necessary to generate important efficacy and preclinical data. In this regard, the humanized mouse models that harbor human hematopoietic cells susceptible to HIV infection provide a suitable in vivo system. This review summarizes the currently used humanized mouse models and different anti-HIV molecules utilized for conferring HIV resistance. Humanized mouse models are compared for their utility in this context and provide perspectives for new directions.
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Affiliation(s)
| | - Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1619 Campus delivery, Fort Collins, CO 80523, USA.
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Marshall L, Cummins J, Spiegel H, Turpin J, Veronese F, Kashuba, on behalf of the HIV Preve A. Critical need for appropriate mucosal sample collection to determine relational animal pharmacokinetic-pharmacodynamic models in HIV prevention. AIDS Res Hum Retroviruses 2013; 29:1398-400. [PMID: 23909474 DOI: 10.1089/aid.2013.0142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Leslie Marshall
- Preclinical Microbicide and Prevention Research Branch, Prevention Sciences Program, Division of AIDS, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland
| | - James Cummins
- Preclinical Microbicide and Prevention Research Branch, Prevention Sciences Program, Division of AIDS, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland
| | - Hans Spiegel
- HJF-DAIDS, a Division of The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Contractor to National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland
| | - James Turpin
- Preclinical Microbicide and Prevention Research Branch, Prevention Sciences Program, Division of AIDS, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland
| | - Fulvia Veronese
- Preclinical Microbicide and Prevention Research Branch, Prevention Sciences Program, Division of AIDS, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland
| | - Angela Kashuba, on behalf of the HIV Preve
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, and UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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40
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Watkins RL, Zou W, Denton PW, Krisko JF, Foster JL, Garcia JV. In vivo analysis of highly conserved Nef activities in HIV-1 replication and pathogenesis. Retrovirology 2013; 10:125. [PMID: 24172637 PMCID: PMC3907037 DOI: 10.1186/1742-4690-10-125] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/23/2013] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The HIV-1 accessory protein, Nef, is decisive for progression to AIDS. In vitro characterization of the protein has described many Nef activities of unknown in vivo significance including CD4 downregulation and a number of activities that depend on Nef interacting with host SH3 domain proteins. Here, we use the BLT humanized mouse model of HIV-1 infection to assess their impact on viral replication and pathogenesis and the selection pressure to restore these activities using enforced in vivo evolution. RESULTS We followed the evolution of HIV-1LAI (LAI) with a frame-shifted nef (LAINeffs) during infection of BLT mice. LAINeffs was rapidly replaced in blood by virus with short deletions in nef that restored the open reading frame (LAINeffs∆-1 and LAINeffs∆-13). Subsequently, LAINeffs∆-1 was often replaced by wild type LAI. Unexpectedly, LAINeffs∆-1 and LAINeffs∆-13 Nefs were specifically defective for CD4 downregulation activity. Viruses with these mutant nefs were used to infect BLT mice. LAINeffs∆-1 and LAINeffs∆-13 exhibited three-fold reduced viral replication (compared to LAI) and a 50% reduction of systemic CD4+ T cells (>90% for LAI) demonstrating the importance of CD4 downregulation. These results also demonstrate that functions other than CD4 downregulation enhanced viral replication and pathogenesis of LAINeffs∆-1 and LAINeffs∆-13 compared to LAINeffs. To gain insight into the nature of these activities, we constructed the double mutant P72A/P75A. Multiple Nef activities can be negated by mutating the SH3 domain binding site (P72Q73V74P75L76R77) to P72A/P75A and this mutation does not affect CD4 downregulation. Virus with nef mutated to P72A/P75A closely resembled the wild-type virus in vivo as viral replication and pathogenesis was not significantly altered. Unlike LAINeffs described above, the P72A/P75A mutation had a very weak tendency to revert to wild type sequence. CONCLUSIONS The in vivo phenotype of Nef is significantly dependent on CD4 downregulation but minimally on the numerous Nef activities that require an intact SH3 domain binding motif. These results suggest that CD4 downregulation plus one or more unknown Nef activities contribute to enhanced viral replication and pathogenesis and are suitable targets for anti-HIV therapy. Enforced evolution studies in BLT mice will greatly facilitate identification of these critical activities.
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Affiliation(s)
- Richard L Watkins
- Division of Infectious Diseases, Center for AIDS Research, 2042 Genetic Medicine, University of North Carolina, Campus Box 7042, Chapel Hill, NC 27599-7042, USA.
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41
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Watkins RL, Zou W, Denton PW, Krisko JF, Foster JL, Garcia JV. In vivo analysis of highly conserved Nef activities in HIV-1 replication and pathogenesis. Retrovirology 2013. [PMID: 24172637 DOI: 10.1186/742-4690-10-125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
BACKGROUND The HIV-1 accessory protein, Nef, is decisive for progression to AIDS. In vitro characterization of the protein has described many Nef activities of unknown in vivo significance including CD4 downregulation and a number of activities that depend on Nef interacting with host SH3 domain proteins. Here, we use the BLT humanized mouse model of HIV-1 infection to assess their impact on viral replication and pathogenesis and the selection pressure to restore these activities using enforced in vivo evolution. RESULTS We followed the evolution of HIV-1LAI (LAI) with a frame-shifted nef (LAINeffs) during infection of BLT mice. LAINeffs was rapidly replaced in blood by virus with short deletions in nef that restored the open reading frame (LAINeffs∆-1 and LAINeffs∆-13). Subsequently, LAINeffs∆-1 was often replaced by wild type LAI. Unexpectedly, LAINeffs∆-1 and LAINeffs∆-13 Nefs were specifically defective for CD4 downregulation activity. Viruses with these mutant nefs were used to infect BLT mice. LAINeffs∆-1 and LAINeffs∆-13 exhibited three-fold reduced viral replication (compared to LAI) and a 50% reduction of systemic CD4+ T cells (>90% for LAI) demonstrating the importance of CD4 downregulation. These results also demonstrate that functions other than CD4 downregulation enhanced viral replication and pathogenesis of LAINeffs∆-1 and LAINeffs∆-13 compared to LAINeffs. To gain insight into the nature of these activities, we constructed the double mutant P72A/P75A. Multiple Nef activities can be negated by mutating the SH3 domain binding site (P72Q73V74P75L76R77) to P72A/P75A and this mutation does not affect CD4 downregulation. Virus with nef mutated to P72A/P75A closely resembled the wild-type virus in vivo as viral replication and pathogenesis was not significantly altered. Unlike LAINeffs described above, the P72A/P75A mutation had a very weak tendency to revert to wild type sequence. CONCLUSIONS The in vivo phenotype of Nef is significantly dependent on CD4 downregulation but minimally on the numerous Nef activities that require an intact SH3 domain binding motif. These results suggest that CD4 downregulation plus one or more unknown Nef activities contribute to enhanced viral replication and pathogenesis and are suitable targets for anti-HIV therapy. Enforced evolution studies in BLT mice will greatly facilitate identification of these critical activities.
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Affiliation(s)
- Richard L Watkins
- Division of Infectious Diseases, Center for AIDS Research, 2042 Genetic Medicine, University of North Carolina, Campus Box 7042, Chapel Hill, NC 27599-7042, USA.
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42
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Vargas-Inchaustegui DA, Robert-Guroff M. Fc receptor-mediated immune responses: new tools but increased complexity in HIV prevention. Curr HIV Res 2013; 11:407-20. [PMID: 24191937 PMCID: PMC6288814 DOI: 10.2174/1570162x113116660063] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/04/2013] [Accepted: 06/06/2013] [Indexed: 12/21/2022]
Abstract
The modest success of the RV144 HIV vaccine trial in Thailand and the ensuing suggestion that a Fc-receptormediated antibody activity might have played a role in the protection observed have intensified investigations on Fcrelated immune responses. HIV neutralizing antibodies have been and continue to be the focal point of research into humoral immune protection. However, recent knowledge that their protective efficacy can be augmented by Fc-FcR interactions has increased the complexity of identifying immune correlates of protection. If anything, continued studies of both humoral and cellular immune mechanisms point to the lack of a single protective anti-HIV immune response. Here we focus on humoral immunity, analyzing the role played by Fc receptor-related responses and discussing how new knowledge of their interactions requires further investigation, but may also spur novel vaccination approaches. We initially address classical Fc-receptor mediated anti-viral mechanisms including antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cell mediated viral inhibition (ADCVI), and antibody-dependent cellular phagocytosis (ADCP), as well as the effector cells that mediate these functions. Next, we summarize key aspects of FcR-Fc interactions that are important for potential control of HIV/SIV such as FcR polymorphisms and post-transcriptional modifications. Finally we discuss less commonly studied non-mechanistic anti-HIV immune functions: antibody avidity and envelopespecific B cell memory. Overall, a spectrum of immune responses, reflecting the immune system's redundancy, will likely be needed to prevent HIV infection and/or disease progression. Aside from elicitation of critical immune mechanisms, a successful vaccine will need to induce mature B cell responses and long-lasting immune memory.
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Affiliation(s)
- Diego A Vargas-Inchaustegui
- Vaccine Branch, Center for Cancer Research, National Cancer Institute, 41 Medlars Drive, Building 41, Room D804, Bethesda, MD 20192-5065, USA.
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Brehm MA, Jouvet N, Greiner DL, Shultz LD. Humanized mice for the study of infectious diseases. Curr Opin Immunol 2013; 25:428-35. [PMID: 23751490 DOI: 10.1016/j.coi.2013.05.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/15/2013] [Accepted: 05/17/2013] [Indexed: 12/17/2022]
Abstract
Many of the pathogens that cause human infectious diseases do not infect rodents or other mammalian species. Small animal models that allow studies of the pathogenesis of these agents and evaluation of drug efficacy are critical for identifying ways to prevent and treat human infectious diseases. Immunodeficient mice engrafted with functional human cells and tissues, termed 'humanized' mice, represent a critical pre-clinical bridge for in vivo studies of human pathogens. Recent advances in the development of humanized mice have allowed in vivo studies of multiple human infectious agents providing novel insights into their pathogenesis that was otherwise not possible.
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Affiliation(s)
- Michael A Brehm
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, United States
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44
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Southern PJ. Missing out on the biology of heterosexual HIV-1 transmission. Trends Microbiol 2013; 21:245-52. [DOI: 10.1016/j.tim.2013.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Revised: 02/03/2013] [Accepted: 02/06/2013] [Indexed: 11/16/2022]
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45
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Akkina R. Human immune responses and potential for vaccine assessment in humanized mice. Curr Opin Immunol 2013; 25:403-9. [PMID: 23628166 DOI: 10.1016/j.coi.2013.03.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 03/27/2013] [Indexed: 12/13/2022]
Abstract
The new humanized mouse models with a transplanted human immune system have a capacity for de novo multilineage human hematopoiesis and generate T cells, B cells, macrophages, dendritic cells and NK cells. Of the two current leading humanized mouse models, the hu-HSC model is created by human hematopoietic stem cell (HSC) engraftment whereas the BLT mouse model is prepared by co-transplantation of human fetal liver, thymus and HSC. Humoral and cellular immune responses are seen in both models after immunization with antigens or infection with hematotropic pathogens such as EBV, HIV-1 and dengue viruses. While consistent antigen specific IgM production is seen, IgG responses were found to be generally feeble which is attributed to inefficient immunoglobulin class switching. BLT mice permit human HLA restricted T cell responses due to the autologous human thymus contributing to T cell maturation. Use of HLA Class I and II transgenic hu-HSC mice recently demonstrated that the HLA restriction deficiency could be overcome in this model. However, the overall vigor of the immune responses needs further improvement in both the models to approach that of the human. Towards this goal, supplementation with human cytokines and growth factors by transgenesis to improve human cell reconstitution and their homeostatic maintenance are beginning to yield improved mouse strains to create more robust human immune competent mice for immunoprophylaxis studies.
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Affiliation(s)
- Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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46
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Adoptive transfer of lymphocytes isolated from simian immunodeficiency virus SIVmac239Δnef-vaccinated macaques does not affect acute-phase viral loads but may reduce chronic-phase viral loads in major histocompatibility complex-matched recipients. J Virol 2013; 87:7382-92. [PMID: 23616658 DOI: 10.1128/jvi.00348-13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The live attenuated simian immunodeficiency virus (SIV) SIVmac239Δnef is the most effective SIV/human immunodeficiency virus (HIV) vaccine in preclinical testing. An understanding of the mechanisms responsible for protection may provide important insights for the development of HIV vaccines. Leveraging the uniquely restricted genetic diversity of Mauritian cynomolgus macaques, we performed adoptive transfers between major histocompatibility complex (MHC)-matched animals to assess the role of cellular immunity in SIVmac239Δnef protection. We vaccinated and mock vaccinated donor macaques and then harvested between 1.25 × 10(9) and 3.0 × 10(9) mononuclear cells from multiple tissues for transfer into 12 naive recipients, followed by challenge with pathogenic SIVmac239. Fluorescently labeled donor cells were detectable for at least 7 days posttransfer and trafficked to multiple tissues, including lung, lymph nodes, and other mucosal tissues. There was no difference between recipient macaques' peak or postpeak plasma viral loads. A very modest difference in viral loads during the chronic phase between vaccinated animal cell recipients and mock-vaccinated animal cell recipients did not reach significance (P = 0.12). Interestingly, the SIVmac239 challenge virus accumulated escape mutations more rapidly in animals that received cells from vaccinated donors. These results may suggest that adoptive transfers influenced the course of infection despite the lack of significant differences in the viral loads among animals that received cells from vaccinated and mock-vaccinated donor animals.
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Chateau ML, Denton PW, Swanson MD, McGowan I, Garcia JV. Rectal transmission of transmitted/founder HIV-1 is efficiently prevented by topical 1% tenofovir in BLT humanized mice. PLoS One 2013; 8:e60024. [PMID: 23527295 PMCID: PMC3603991 DOI: 10.1371/journal.pone.0060024] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 02/23/2013] [Indexed: 12/21/2022] Open
Abstract
Rectal microbicides are being developed to prevent new HIV infections in both men and women. We focused our in vivo preclinical efficacy study on rectally-applied tenofovir. BLT humanized mice (n = 43) were rectally inoculated with either the primary isolate HIV-1JRCSF or the MSM-derived transmitted/founder (T/F) virus HIV-1THRO within 30 minutes following treatment with topical 1% tenofovir or vehicle. Under our experimental conditions, in the absence of drug treatment we observed 50% and 60% rectal transmission by HIV-1JRCSF and HIV-1THRO, respectively. Topical tenofovir reduced rectal transmission to 8% (1/12; log rank p = 0.03) for HIV-1JRCSF and 0% (0/6; log rank p = 0.02) for HIV-1THRO. This is the first demonstration that any human T/F HIV-1 rectally infects humanized mice and that transmission of the T/F virus can be efficiently blocked by rectally applied 1% tenofovir. These results obtained in BLT mice, along with recent ex vivo, Phase 1 trial and non-human primate reports, provide a critically important step forward in the development of tenofovir-based rectal microbicides.
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Affiliation(s)
- Morgan L. Chateau
- Division of Infectious Diseases, Department of Internal Medicine, Center for AIDS Research University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Paul W. Denton
- Division of Infectious Diseases, Department of Internal Medicine, Center for AIDS Research University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Michael D. Swanson
- Division of Infectious Diseases, Department of Internal Medicine, Center for AIDS Research University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Ian McGowan
- Magee-Womens Research Institute, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America
| | - J. Victor Garcia
- Division of Infectious Diseases, Department of Internal Medicine, Center for AIDS Research University of North Carolina, Chapel Hill, North Carolina, United States of America
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48
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Akkina R. New generation humanized mice for virus research: comparative aspects and future prospects. Virology 2013; 435:14-28. [PMID: 23217612 DOI: 10.1016/j.virol.2012.10.007] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 10/03/2012] [Accepted: 10/03/2012] [Indexed: 12/27/2022]
Abstract
Work with human specific viruses will greatly benefit from the use of an in vivo system that provides human target cells and tissues in a physiological setting. In this regard humanized mice (hu-Mice) have played an important role in our understanding of viral pathogenesis and testing of therapeutic strategies. Limitations with earlier versions of hu-Mice that lacked a functioning human immune system are currently being overcome. The new generation hu-Mouse models are capable of multilineage human hematopoiesis and generate T cells, B cells, macrophages and dendritic cells required for an adaptive human immune response. Now any human specific pathogen that can infect humanized mice can be studied in the context of ongoing infection and immune responses. Two leading humanized mouse models are currently employed: the hu-HSC model is created by transplantation of human hematopoietic stem cells (HSC), whereas the BLT mouse model is prepared by transplantation of human fetal liver, thymus and HSC. A number of human specific viruses such as HIV-1, dengue, EBV and HCV are being studied intensively in these systems. Both models permit infection by mucosal routes with viruses such as HIV-1 thus allowing transmission prevention studies. Cellular and humoral immune responses are seen in both the models. While there is efficient antigen specific IgM production, IgG responses are suboptimal due to inefficient immunoglobulin class switching. With the maturation of T cells occurring in the autologous human thymus, BLT mice permit human HLA restricted T cell responses in contrast to hu-HSC mice. However, the strength of the immune responses needs further improvement in both models to reach the levels seen in humans. The scope of hu-Mice use is further broadened by transplantation of additional tissues like human liver thus permitting immunopathogenesis studies on hepatotropic viruses such as HCV. Numerous studies that encompass antivirals, gene therapy, viral evolution, and the generation of human monoclonal antibodies have been conducted with promising results in these mice. For further improvement of the new hu-Mouse models, ongoing work is focused on generating new strains of immunodeficient mice transgenic for human HLA molecules to strengthen immune responses and human cytokines and growth factors to improve human cell reconstitution and their homeostatic maintenance.
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Affiliation(s)
- Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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Deeks S, Drosten C, Picker L, Subbarao K, Suzich J. Roadblocks to translational challenges on viral pathogenesis. Nat Med 2013; 19:30-4. [PMID: 23296014 PMCID: PMC7095913 DOI: 10.1038/nm.3050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Distinct roadblocks prevent translating basic findings in viral pathogenesis into therapies and implementing potential solutions in the clinic. An ongoing partnership between the Volkswagen Foundation and Nature Medicine resulted in an interactive meeting in 2012, as part of the "Herrenhausen Symposia" series. Current challenges for various fields of viral research were recognized and discussed with a goal in mind--to identify solutions and propose an agenda to address the translational barriers. Here, some of the researchers who participated at the meeting provide a concise outlook at the most pressing unmet research and clinical needs, identifying these key obstacles is a necessary step towards the prevention and cure of human viral diseases.
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Affiliation(s)
- Steven Deeks
- Steven Deeks is at the Department of Medicine, University of California–San Francisco, San Francisco, California, USA.,
| | - Christian Drosten
- Christian Drosten is at the Institute of Virology, University of Bonn Medical Centre, Bonn, Germany.,
| | - Louis Picker
- Louis Picker is at the Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, USA.,
| | - Kanta Subbarao
- Kanta Subbarao is at the Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.,
| | - JoAnn Suzich
- JoAnn Suzich is at MedImmune, Gaithersburg, Maryland, USA.,
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50
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Purcell D, Cunningham A, Turville S, Tachedjian G, Landay A. Biology of mucosally transmitted sexual infection-translating the basic science into novel HIV intervention: a workshop summary. AIDS Res Hum Retroviruses 2012; 28:1389-96. [PMID: 22966898 DOI: 10.1089/aid.2012.0276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A group of over 200 international scientists came together on April 15 in Sydney, Australia just before the 2012 International Microbicides Conference as a part of a workshop to address the basic concepts and factors that modulate HIV infection at the mucosal surface. The meeting focused on defining the interaction between virus, prevailing host physiology, microbiota, and innate and adaptive immune responses and how they combine to impact the outcome at the moment of potential viral transmission. Speakers examined the biology of HIV entry during transmission, innate and natural antiviral mechanisms at the mucosa, microbicide efficacy, pharmacokinetic, and pharmacodynamics, animal models, and opportunities for combining HIV prevention strategies. Other viral infection models both in vivo and in vitro were considered for the insights they provided into HIV transmission events. The workshop raised important questions that we need to answer to further our basic understanding of host and viral factors influencing HIV transmission to inform the development of novel prevention strategies.
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