1
|
Li X, Zhao Y, Teng QY, Zhang XH, Xue J, Zhang GZ. Methyltransferase K-D-K-E motif influences the intercellular transmission of Newcastle disease virus. Virulence 2023; 14:2186336. [PMID: 36919461 PMCID: PMC10026920 DOI: 10.1080/21505594.2023.2186336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
We previously demonstrated that two methyltransferase motifs, K-D-K-E and G-G-D, affect the pathogenicity of Newcastle disease virus (NDV) by regulating mRNA translation and virus transmission. Here, we compared the infectious centre area produced by the NDV strain, rSG10, and methyltransferase motifs mutant rSG10 strains in DF-1 cells. The results show that intercellular transmission was attenuated by methyltransferase motif mutations. We further determined the ability of mutant viruses to spread in cell-free and cell-to-cell situations. Cell-free transmission of rSG10-K1756A was not reduced, indicating that cell-to-cell transmission of rSG10-K1756A was decreased. Using a donor and target system, we demonstrated that NDV can spread from cell-to-cell directly. Furthermore, by comparing the protein distribution area of three strains when treated with 2% agar overlay, we found that rSG10-K1756A was defective in cell-to-cell transmission. Tunnelling nanotubes (TNTs) are an important mode for cell-to-cell transmission. Treatment of cells with cytochalasin D (CytoD) or nocodazole to inhibit the formation of TNTs, reduced protein levels in all strains, but rSG10-K1756A was the least affected. These results indicate that mutation of the K-D-K-E motif is likely to restricted the spread of NDV via TNTs. Finally, we observed that matrix protein (M) and fusion protein (F) promoted the formation of cellular extensions, which may be involved in the cell-to-cell spread of NDV. Our research reveals a novel mechanism by which methyltransferase motifs affect the cell-to-cell spread of NDV and provides insight into dissemination of paramyxoviruses.
Collapse
Affiliation(s)
- Xiao Li
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Ye Zhao
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Qing-Yuan Teng
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xue-Hui Zhang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jia Xue
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Guo-Zhong Zhang
- Key Laboratory of Animal Epidemiology of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| |
Collapse
|
2
|
Fujino H, Sonoda-Fukuda E, Isoda L, Kawabe A, Takarada T, Kasahara N, Kubo S. Retroviral Replicating Vectors Mediated Prodrug Activator Gene Therapy in a Gastric Cancer Model. Int J Mol Sci 2023; 24:14823. [PMID: 37834271 PMCID: PMC10573151 DOI: 10.3390/ijms241914823] [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: 08/04/2023] [Revised: 09/29/2023] [Accepted: 09/29/2023] [Indexed: 10/15/2023] Open
Abstract
Retroviral replicating vectors (RRVs) selectively replicate and can specifically introduce prodrug-activating genes into tumor cells, whereby subsequent prodrug administration induces the death of the infected tumor cells. We assessed the ability of two distinct RRVs generated from amphotropic murine leukemia virus (AMLV) and gibbon ape leukemia virus (GALV), which infect cells via type-III sodium-dependent phosphate transporters, PiT-2 and PiT-1, respectively, to infect human gastric cancer (GC) cells. A quantitative RT-PCR showed that all tested GC cell lines had higher expression levels of PiT-2 than PiT-1. Accordingly, AMLV, encoding a green fluorescent protein gene, infected and replicated more efficiently than GALV in most GC cell lines, whereas both RRVs had a low infection rate in human fibroblasts. RRV encoding a cytosine deaminase prodrug activator gene, which converts the prodrug 5-flucytosine (5-FC) to the active drug 5-fluorouracil, showed that AMLV promoted superior 5-FC-induced cytotoxicity compared with GALV, which correlated with the viral receptor expression level and viral spread. In MKN-74 subcutaneous xenograft models, AMLV had significant antitumor effects compared with GALV. Furthermore, in the MKN-74 recurrent tumor model in which 5-FC was discontinued, the resumption of 5-FC administration reduced the tumor volume. Thus, RRV-mediated prodrug activator gene therapy might be beneficial for treating human GC.
Collapse
Affiliation(s)
- Hiroaki Fujino
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
- Departments of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Emiko Sonoda-Fukuda
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
| | - Lisa Isoda
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
- Departments of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Ayane Kawabe
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
- Departments of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Toru Takarada
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
- Laboratory of Functional Molecular Chemistry, Kobe Pharmaceutical University, Hyogo 658-8558, Japan
| | - Noriyuki Kasahara
- Departments of Neurological Surgery and Radiation Oncology, University of California, San Francisco, CA 94143, USA;
| | - Shuji Kubo
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Hyogo 663-8501, Japan (L.I.); (T.T.)
| |
Collapse
|
3
|
Itabashi K, Miyazawa T, Uchimaru K. How Can We Prevent Mother-to-Child Transmission of HTLV-1? Int J Mol Sci 2023; 24:ijms24086961. [PMID: 37108125 PMCID: PMC10138424 DOI: 10.3390/ijms24086961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
The perception of human T-cell leukemia virus type 1 (HTlV-1) infection as a "silent disease" has recently given way to concern that its presence may be having a variety of effects. HTLV-1 is known to cause adult T-cell leukemia (ATL), an aggressive cancer of peripheral CD4 T cells; however, it is also responsible for HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Most patients develop ATL as a result of HTLV-1 mother-to-child transmission. The primary route of mother-to-child transmission is through the mother's milk. In the absence of effective drug therapy, total artificial nutrition such as exclusive formula feeding is a reliable means of preventing mother-to-child transmission after birth, except for a small percentage of prenatal infections. A recent study found that the rate of mother-to-child transmission with short-term breastfeeding (within 90 days) did not exceed that of total artificial nutrition. Because these preventive measures are in exchange for the benefits of breastfeeding, clinical applications of antiretroviral drugs and immunotherapy with vaccines and neutralizing antibodies are urgently needed.
Collapse
Affiliation(s)
- Kazuo Itabashi
- Aiseikai-Memorial Ibaraki Welfare and Medical Center, Ibaraki 3100836, Japan
| | - Tokuo Miyazawa
- Department of Pediatrics, Showa University School of Medicine, Tokyo 1428666, Japan
| | - Kaoru Uchimaru
- Department of Hematology/Oncology, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo 1088639, Japan
- Laboratory of Tumor Cell Biology, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 1088639, Japan
| |
Collapse
|
4
|
Couteaudier M, Montange T, Njouom R, Bilounga-Ndongo C, Gessain A, Buseyne F. Plasma antibodies from humans infected with zoonotic simian foamy virus do not inhibit cell-to-cell transmission of the virus despite binding to the surface of infected cells. PLoS Pathog 2022; 18:e1010470. [PMID: 35605011 PMCID: PMC9166401 DOI: 10.1371/journal.ppat.1010470] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 06/03/2022] [Accepted: 03/25/2022] [Indexed: 01/23/2023] Open
Abstract
Zoonotic simian foamy viruses (SFV) establish lifelong infection in their human hosts. Despite repeated transmission of SFV from nonhuman primates to humans, neither transmission between human hosts nor severe clinical manifestations have been reported. We aim to study the immune responses elicited by chronic infection with this retrovirus and previously reported that SFV-infected individuals generate potent neutralizing antibodies that block cell infection by viral particles. Here, we assessed whether human plasma antibodies block SFV cell-to-cell transmission and present the first description of cell-to-cell spreading of zoonotic gorilla SFV. We set-up a microtitration assay to quantify the ability of plasma samples from 20 Central African individuals infected with gorilla SFV and 9 uninfected controls to block cell-associated transmission of zoonotic gorilla SFV strains. We used flow-based cell cytometry and fluorescence microscopy to study envelope protein (Env) localization and the capacity of plasma antibodies to bind to infected cells. We visualized the cell-to-cell spread of SFV by real-time live imaging of a GFP-expressing prototype foamy virus (CI-PFV) strain. None of the samples neutralized cell-associated SFV infection, despite the inhibition of cell-free virus. We detected gorilla SFV Env in the perinuclear region, cytoplasmic vesicles and at the cell surface. We found that plasma antibodies bind to Env located at the surface of cells infected with primary gorilla SFV strains. Extracellular labeling of SFV proteins by human plasma samples showed patchy staining at the base of the cell and dense continuous staining at the cell apex, as well as staining in the intercellular connections that formed when previously connected cells separated from each other. In conclusion, SFV-specific antibodies from infected humans do not block cell-to-cell transmission, at least in vitro, despite their capacity to bind to the surface of infected cells. Trial registration: Clinical trial registration: www.clinicaltrials.gov, https://clinicaltrials.gov/ct2/show/NCT03225794/. Foamy viruses are the oldest known retroviruses and have been mostly described to be nonpathogenic in their natural animal hosts. Simian foamy viruses (SFVs) can be transmitted to humans, in whom they establish persistent infection, as have the simian viruses that led to the emergence of two major human pathogens, human immunodeficiency virus type 1 (HIV-1) and human T lymphotropic virus type 1 (HTLV-1). Such cross-species transmission of SFV is ongoing in many parts of the world where humans have contact with nonhuman primates. We previously showed high titers of neutralizing antibodies in the plasma of most SFV-infected individuals. These antiviral antibodies can inhibit cell-free virus entry. However, SFV efficiently spread from one cell to another. Here, we demonstrate that plasma antibodies do not block such cell-to-cell transmission, despite their capacity to bind to the surface of infected cells. In addition, we document for the first time the cell-to-cell spread of primary zoonotic gorilla SFV.
Collapse
Affiliation(s)
- Mathilde Couteaudier
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Paris, France
| | - Thomas Montange
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Paris, France
| | | | | | - Antoine Gessain
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Paris, France
| | - Florence Buseyne
- Institut Pasteur, Université Paris Cité, CNRS UMR3569, Unité d’Epidémiologie et Physiopathologie des Virus Oncogènes, Paris, France
- * E-mail:
| |
Collapse
|
5
|
Role of Apoptosis in HIV Pathogenesis. Adv Virol 2022; 2022:8148119. [PMID: 35462964 PMCID: PMC9023228 DOI: 10.1155/2022/8148119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/08/2022] [Accepted: 03/28/2022] [Indexed: 11/18/2022] Open
Abstract
The apoptotic pathway is an important cell death pathway that contributes to the maintenance of homeostasis in living systems. However, variations in apoptosis have been linked to many diseases such as cancers and chronic infections. The HIV infection has contributed to increase mortality and morbidity worldwide, predominantly through the induction of gradual depletion of CD4+ T cells. The induction and mediation of both the intrinsic and extrinsic apoptotic pathways are crucial in HIV pathogenesis and intracellular survival. Consequently, a deep molecular understanding of how apoptosis is induced and modulated in HIV-mediated CD4+ T cell depletion is paramount, as this can lead to new portals of therapeutic intervention and control.
Collapse
|
6
|
Bystander CD4 T-cell death is inhibited by broadly neutralizing anti-HIV antibodies only at levels blocking cell-to-cell viral transmission. J Biol Chem 2021; 297:101098. [PMID: 34418431 PMCID: PMC8446805 DOI: 10.1016/j.jbc.2021.101098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 06/28/2021] [Accepted: 08/17/2021] [Indexed: 11/23/2022] Open
Abstract
The progressive loss of CD4+ T cells during HIV infection of lymphoid tissues involves both the apoptotic death of activated and productively infected CD4 T cells and the pyroptotic death of large numbers of resting and abortively infected bystander CD4 T cells. HIV spreads both through cellular release of virions and cell-to-cell transmission involving the formation of virological synapses. Cell-to-cell transmission results in high-level transfer of large quantities of virions to the target cell exceeding that achieved with cell-free virions. Broadly neutralizing anti-HIV antibodies (bNAbs) binding to HIV envelope protein capably block cell-free virus spread, and when added at higher concentrations can also interdict cell-to-cell transmission. Exploiting these distinct dose–response differences, we now show that four different bNAbs block the pyroptotic death of bystander cells, but only when added at concentrations sufficient to block cell-to-cell transmission. These findings further support the conclusion that HIV killing of abortively infected bystander CD4 T cells requires cell-to-cell transfer of virions. As bNAbs attract more interest as potential therapeutics, it will be important to consider the higher concentrations of these antibodies required to block the inflammatory death of bystander CD4 T cells.
Collapse
|
7
|
Wang Q, Su S, Xue J, Yu F, Pu J, Bi W, Xia S, Meng Y, Wang C, Yang W, Xu W, Zhu Y, Zheng Q, Qin C, Jiang S, Lu L. An amphipathic peptide targeting the gp41 cytoplasmic tail kills HIV-1 virions and infected cells. Sci Transl Med 2021; 12:12/546/eaaz2254. [PMID: 32493792 DOI: 10.1126/scitranslmed.aaz2254] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 04/28/2020] [Indexed: 12/26/2022]
Abstract
HIV-associated morbidity and mortality have markedly declined because of combinational antiretroviral therapy, but HIV readily mutates to develop drug resistance. Developing antivirals against previously undefined targets is essential to treat existing drug-resistant HIV strains. Some peptides derived from HIV-1 envelope glycoprotein (Env, gp120-gp41) have been shown to be effective in inhibiting HIV-1 infection. Therefore, we screened a peptide library from HIV-1 Env and identified a peptide from the cytoplasmic region, designated F9170, able to effectively inactivate HIV-1 virions and induce necrosis of HIV-1-infected cells, and reactivated latently infected cells. F9170 specifically targeted the conserved cytoplasmic tail of HIV-1 Env and effectively disrupted the integrity of the viral membrane. Short-term monoadministration of F9170 controlled viral loads to below the limit of detection in chronically SHIV-infected macaques. F9170 can enter the brain and lymph nodes, anatomic reservoirs for HIV latency. Therefore, F9170 shows promise as a drug candidate for HIV treatment.
Collapse
Affiliation(s)
- Qian Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Shan Su
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Jing Xue
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Re-emerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing 100021, China
| | - Fei Yu
- College of Life and Science, Hebei Agricultural University, Baoding 071001, China
| | - Jing Pu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wenwen Bi
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Shuai Xia
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Yu Meng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Cong Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wenqian Yang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wei Xu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Yun Zhu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qinwen Zheng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Chuan Qin
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Re-emerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing 100021, China.
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China. .,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| |
Collapse
|
8
|
Singh R, Ramsuran V, Naranbhai V, Yende-Zuma N, Garrett N, Mlisana K, Dong KL, Walker BD, Abdool Karim SS, Carrington M, Ndung'u T. Epigenetic Regulation of BST-2 Expression Levels and the Effect on HIV-1 Pathogenesis. Front Immunol 2021; 12:669241. [PMID: 34025670 PMCID: PMC8131512 DOI: 10.3389/fimmu.2021.669241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/20/2021] [Indexed: 11/23/2022] Open
Abstract
HIV-1 must overcome host antiviral restriction factors for efficient replication. We hypothesized that elevated levels of bone marrow stromal cell antigen 2 (BST-2), a potent host restriction factor that interferes with HIV-1 particle release in some human cells and is antagonized by the viral protein Vpu, may associate with viral control. Using cryopreserved samples, from HIV-1 seronegative and seropositive Black women, we measured in vitro expression levels of BST-2 mRNA using a real-time PCR assay and protein levels were validated by Western blotting. The expression level of BST-2 showed an association with viral control within two independent cohorts of Black HIV infected females (r=-0.53, p=0.015, [n =21]; and r=-0.62, p=0.0006, [n=28]). DNA methylation was identified as a mechanism regulating BST-2 levels, where increased BST-2 methylation results in lower expression levels and associates with worse HIV disease outcome. We further demonstrate the ability to regulate BST-2 levels using a DNA hypomethylation drug. Our results suggest BST-2 as a factor for potential therapeutic intervention against HIV and other diseases known to involve BST-2.
Collapse
Affiliation(s)
- Ravesh Singh
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.,Africa Health Research Institute (AHRI), Durban, South Africa.,Department of Microbiology, National Health Laboratory Services, KZN Academic Complex, Inkosi Albert Luthuli Central Hospital, Durban, South Africa
| | - Veron Ramsuran
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.,The Ragon Institute of MGH, MIT and Harvard University, Cambridge, MA, United States.,Basic Science Program, Frederick National Laboratory for Cancer Research in the Laboratory of Integrative Cancer Immunology, Bethesda, MD, United States.,Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Vivek Naranbhai
- The Ragon Institute of MGH, MIT and Harvard University, Cambridge, MA, United States.,Basic Science Program, Frederick National Laboratory for Cancer Research in the Laboratory of Integrative Cancer Immunology, Bethesda, MD, United States.,Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Nonhlanhla Yende-Zuma
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Nigel Garrett
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Koleka Mlisana
- Department of Microbiology, National Health Laboratory Services, KZN Academic Complex, Inkosi Albert Luthuli Central Hospital, Durban, South Africa
| | - Krista L Dong
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Bruce D Walker
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.,Africa Health Research Institute (AHRI), Durban, South Africa.,The Ragon Institute of MGH, MIT and Harvard University, Cambridge, MA, United States
| | - Salim S Abdool Karim
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Mary Carrington
- The Ragon Institute of MGH, MIT and Harvard University, Cambridge, MA, United States.,Basic Science Program, Frederick National Laboratory for Cancer Research in the Laboratory of Integrative Cancer Immunology, Bethesda, MD, United States
| | - Thumbi Ndung'u
- HIV Pathogenesis Programme, Doris Duke Medical Research Institute, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.,Africa Health Research Institute (AHRI), Durban, South Africa.,The Ragon Institute of MGH, MIT and Harvard University, Cambridge, MA, United States.,Max Planck Institute for Infection Biology, Chariteplatz, Berlin, Germany.,Division of Infection and Immunity, University College London, London, United Kingdom
| |
Collapse
|
9
|
Kongsomros S, Manopwisedjaroen S, Chaopreecha J, Wang SF, Borwornpinyo S, Thitithanyanont A. Rapid and Efficient Cell-to-Cell Transmission of Avian Influenza H5N1 Virus in MDCK Cells Is Achieved by Trogocytosis. Pathogens 2021; 10:483. [PMID: 33923524 PMCID: PMC8074074 DOI: 10.3390/pathogens10040483] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/31/2021] [Accepted: 04/07/2021] [Indexed: 01/14/2023] Open
Abstract
Viruses have developed direct cell-to-cell transfer strategies to enter target cells without being released to escape host immune responses and antiviral treatments. These strategies are more rapid and efficient than transmission through indirect mechanisms of viral infection between cells. Here, we demonstrate that an H5N1 influenza virus can spread via direct cell-to-cell transfer in Madin-Darby canine kidney (MDCK) cells. We compared cell-to-cell transmission of the H5N1 virus to that of a human influenza H1N1 virus. The H5N1 virus has been found to spread to recipient cells faster than the human influenza H1N1 virus. Additionally, we showed that plasma membrane exchange (trogocytosis) occurs between co-cultured infected donor cells and uninfected recipient cells early point, allowing the intercellular transfer of viral material to recipient cells. Notably, the H5N1 virus induced higher trogocytosis levels than the H1N1 virus, which could explain the faster cell-to-cell transmission rate of H5N1. Importantly, this phenomenon was also observed in A549 human lung epithelial cells, which are representative cells in the natural infection site. Altogether, our results provide evidence demonstrating that trogocytosis could be the additional mechanism utilized by the H5N1 virus for rapid and efficient cell-to-cell transmission.
Collapse
Affiliation(s)
- Supasek Kongsomros
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (S.K.); (S.M.); (J.C.)
| | - Suwimon Manopwisedjaroen
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (S.K.); (S.M.); (J.C.)
| | - Jarinya Chaopreecha
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (S.K.); (S.M.); (J.C.)
| | - Sheng-Fan Wang
- Department of Medical Laboratory Sciences and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung 80708, Taiwan;
| | - Suparerk Borwornpinyo
- Excellence Center for Drug Discovery (ECDD), Faculty of Science, Mahidol University, Bangkok 10400, Thailand;
- Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Arunee Thitithanyanont
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; (S.K.); (S.M.); (J.C.)
| |
Collapse
|
10
|
Zhang T, Wang J, Li Y, Jiang Z, Han X. Dynamics analysis of a delayed virus model with two different transmission methods and treatments. ADVANCES IN DIFFERENCE EQUATIONS 2020; 2020:1. [PMID: 32226454 PMCID: PMC7100214 DOI: 10.1186/s13662-019-2438-0] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/29/2019] [Indexed: 05/07/2023]
Abstract
In this paper, a delayed virus model with two different transmission methods and treatments is investigated. This model is a time-delayed version of the model in (Zhang et al. in Comput. Math. Methods Med. 2015:758362, 2015). We show that the virus-free equilibrium is locally asymptotically stable if the basic reproduction number is smaller than one, and by regarding the time delay as a bifurcation parameter, the existence of local Hopf bifurcation is investigated. The results show that time delay can change the stability of the endemic equilibrium. Finally, we give some numerical simulations to illustrate the theoretical findings.
Collapse
Affiliation(s)
- Tongqian Zhang
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, P.R. China
| | - Junling Wang
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, P.R. China
| | - Yuqing Li
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, P.R. China
| | - Zhichao Jiang
- Fundamental Science Department, North China Institute of Aerospace Engineering, Langfang, P.R. China
| | - Xiaofeng Han
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, P.R. China
| |
Collapse
|
11
|
Zotova A, Atemasova A, Pichugin A, Filatov A, Mazurov D. Distinct Requirements for HIV-1 Accessory Proteins during Cell Coculture and Cell-Free Infection. Viruses 2019; 11:v11050390. [PMID: 31027334 PMCID: PMC6563509 DOI: 10.3390/v11050390] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/24/2019] [Accepted: 04/25/2019] [Indexed: 12/15/2022] Open
Abstract
The role of accessory proteins during cell-to-cell transmission of HIV-1 has not been explicitly defined. In part, this is related to difficulties in measuring virus replication in cell cocultures with high accuracy, as cells coexist at different stages of infection and separation of effector cells from target cells is complicated. In this study, we used replication-dependent reporter vectors to determine requirements for Vif, Vpu, Vpr, or Nef during one cycle of HIV-1 cell coculture and cell-free infection in lymphoid and nonlymphoid cells. Comparative analysis of HIV-1 replication in two cell systems showed that, irrespective of transmission way, accessory proteins were generally less required for virus replication in 293T/CD4/X4 cells than in Jurkat-to-Raji/CD4 cell cocultures. This is consistent with a well-established fact that lymphoid cells express a broad spectrum of restriction factors, while nonlymphoid cells are rather limited in this regard. Remarkably, Vpu deletion reduced the level of cell-free infection, but enhanced the level of cell coculture infection and increased the fraction of multiply infected cells. Nef deficiency did not influence or moderately reduced HIV-1 infection in nonlymphoid and lymphoid cell cocultures, respectively, but strongly affected cell-free infection. Knockout of BST2-a Vpu antagonizing restriction factor-in Jurkat producer cells abolished the enhanced replication of HIV-1 ΔVpu in cell coculture and prevented the formation of viral clusters on cell surface. Thus, BST2-tethered viral particles mediated cell coculture infection more efficiently and at a higher level of multiplicity than diffusely distributed virions. In conclusion, our results demonstrate that the mode of transmission may determine the degree of accessory protein requirements during HIV-1 infection.
Collapse
Affiliation(s)
- Anastasia Zotova
- Cell and Gene Technology Group, Institute of Gene Biology RAS, 34/5 Vavilova Street, 119334 Moscow, Russia.
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119991 Moscow, Russia.
| | - Anastasia Atemasova
- Faculty of Biology, Lomonosov Moscow State University, 1-12 Leninskie Gory, 119991 Moscow, Russia.
| | - Alexey Pichugin
- NRC Institute of Immunology FMBA of Russia, 24 Kashirskoe Shosse, 115472 Moscow, Russia.
| | - Alexander Filatov
- NRC Institute of Immunology FMBA of Russia, 24 Kashirskoe Shosse, 115472 Moscow, Russia.
| | - Dmitriy Mazurov
- Cell and Gene Technology Group, Institute of Gene Biology RAS, 34/5 Vavilova Street, 119334 Moscow, Russia.
- NRC Institute of Immunology FMBA of Russia, 24 Kashirskoe Shosse, 115472 Moscow, Russia.
| |
Collapse
|
12
|
Fernandez MV, Freed EO. Meeting Review: 2018 International Workshop on Structure and Function of the Lentiviral gp41 Cytoplasmic Tail. Viruses 2018; 10:E613. [PMID: 30405009 PMCID: PMC6266243 DOI: 10.3390/v10110613] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 11/03/2018] [Indexed: 01/09/2023] Open
Abstract
Recent developments in defining the role of the lentiviral envelope glycoprotein (Env) cytoplasmic tail (CT) in Env trafficking and incorporation into virus particles have advanced our understanding of viral replication and transmission. To stimulate additional progress in this field, the two-day International Workshop on Structure and Function of the Lentiviral gp41 Cytoplasmic Tail, co-organized by Eric Freed and James Hoxie, was held at the National Cancer Institute in Frederick, MD (26⁻27 April 2018). The meeting served to bring together experts focused on the role of gp41 in HIV replication and to discuss the emerging mechanisms of CT-dependent trafficking, Env conformation and structure, host protein interaction, incorporation, and viral transmission. The conference was organized around the following three main hot topics in gp41 research: the role of host factors in CT-dependent Env incorporation, Env structure, and CT-mediated trafficking and transmission. This review highlights important topics and the advances in gp41 research that were discussed during the conference.
Collapse
Affiliation(s)
- Melissa V Fernandez
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| | - Eric O Freed
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA.
| |
Collapse
|
13
|
Lee WYJ, Fu RM, Liang C, Sloan RD. IFITM proteins inhibit HIV-1 protein synthesis. Sci Rep 2018; 8:14551. [PMID: 30266929 PMCID: PMC6162285 DOI: 10.1038/s41598-018-32785-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 09/11/2018] [Indexed: 01/23/2023] Open
Abstract
Interferon induced transmembrane proteins (IFITMs) inhibit the cellular entry of a broad range of viruses, but it has been suspected that for HIV-1 IFITMs may also inhibit a post-integration replicative step. We show that IFITM expression reduces HIV-1 viral protein synthesis by preferentially excluding viral mRNA transcripts from translation and thereby restricts viral production. Codon-optimization of proviral DNA rescues viral translation, implying that IFITM-mediated restriction requires recognition of viral RNA elements. In addition, we find that expression of the viral accessory protein Nef can help overcome the IFITM-mediated inhibition of virus production. Our studies identify a novel role for IFITMs in inhibiting HIV replication at the level of translation, but show that the effects can be overcome by the lentiviral protein Nef.
Collapse
Affiliation(s)
- Wing-Yiu Jason Lee
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - Rebecca Menhua Fu
- Division of Infection and Pathway Medicine, School of Biomedical Sciences, University of Edinburgh, Edinburgh, EH16 4SB, United Kingdom
| | - Chen Liang
- McGill University AIDS Centre, Lady Davis Institute, Montreal, Quebec, H3T 1E2, Canada
| | - Richard D Sloan
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom.
- Division of Infection and Pathway Medicine, School of Biomedical Sciences, University of Edinburgh, Edinburgh, EH16 4SB, United Kingdom.
- ZJU-UoE Institute, Zhejiang University, Haining, Zhejiang, 314400, P.R. China.
| |
Collapse
|
14
|
Kuno A, Nishimura K, Takahashi S. Time-course transcriptome analysis of human cellular reprogramming from multiple cell types reveals the drastic change occurs between the mid phase and the late phase. BMC Genomics 2018; 19:9. [PMID: 29298685 PMCID: PMC5753469 DOI: 10.1186/s12864-017-4389-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 12/15/2017] [Indexed: 11/10/2022] Open
Abstract
Background Human induced pluripotent stem cells (hiPSCs) have been attempted for clinical application with diverse iPSCs sources derived from various cell types. This proposes that there would be a shared reprogramming route regardless of different starting cell types. However, the insights of reprogramming process are mostly restricted to only fibroblasts of both human and mouse. To understand molecular mechanisms of cellular reprogramming, the investigation of the conserved reprogramming routes from various cell types is needed. Particularly, the maturation, belonging to the mid phase of reprogramming, was reported as the main roadblock of reprogramming from human dermal fibroblasts to hiPSCs. Therefore, we investigated first whether the shared reprogramming routes exists across various human cell types and second whether the maturation is also a major blockage of reprogramming in various cell types. Results We selected 3615 genes with dynamic expressions during reprogramming from five human starting cell types by using time-course microarray dataset. Then, we analyzed transcriptomic variances, which were clustered into 3 distinct transcriptomic phases (early, mid and late phase); and greatest difference lied in the late phase. Moreover, functional annotation of gene clusters classified by gene expression patterns showed the mesenchymal-epithelial transition from day 0 to 3, transient upregulation of epidermis related genes from day 7 to 15, and upregulation of pluripotent genes from day 20, which were partially similar to the reprogramming process of mouse embryonic fibroblasts. We lastly illustrated variations of transcription factor activity at each time point of the reprogramming process and a major differential transition of transcriptome in between day 15 to 20 regardless of cell types. Therefore, the results implied that the maturation would be a major roadblock across multiple cell types in the human reprogramming process. Conclusions Human cellular reprogramming process could be traced into three different phases across various cell types. As the late phase exhibited the greatest dissimilarity, the maturation step could be suggested as the common major roadblock during human cellular reprogramming. To understand further molecular mechanisms of the maturation would enhance reprogramming efficiency by overcoming the roadblock during hiPSCs generation. Electronic supplementary material The online version of this article (10.1186/s12864-017-4389-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Akihiro Kuno
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan. .,Ph.D Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan.
| | - Ken Nishimura
- Laboratory of Gene Regulation, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| |
Collapse
|
15
|
Abstract
Co-infection with Mycobacterium tuberculosis is the leading cause of death in individuals infected with HIV-1. It has long been known that HIV-1 infection alters the course of M. tuberculosis infection and substantially increases the risk of active tuberculosis (TB). It has also become clear that TB increases levels of HIV-1 replication, propagation and genetic diversity. Therefore, co-infection provides reciprocal advantages to both pathogens. In this Review, we describe the epidemiological associations between the two pathogens, selected interactions of each pathogen with the host and our current understanding of how they affect the pathogenesis of TB and HIV-1/AIDS in individuals with co-infections. We evaluate the mechanisms and consequences of HIV-1 depletion of T cells on immune responses to M. tuberculosis. We also discuss the effect of HIV-1 infection on the control of M. tuberculosis by macrophages through phagocytosis, autophagy and cell death, and we propose models by which dysregulated inflammatory responses drive the pathogenesis of TB and HIV-1/AIDS.
Collapse
|
16
|
A novel HIV-1 gp41 tripartite model for rational design of HIV-1 fusion inhibitors with improved antiviral activity. AIDS 2017; 31:885-894. [PMID: 28121713 DOI: 10.1097/qad.0000000000001415] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES During HIV-1 fusion process, the N-terminal heptad repeat (NHR) of the HIV-1 glycoprotein 41 (gp41) interacts with the C-terminal heptad repeat (CHR) to form the fusion active six-helix bundle, thus being an effective target for the design of CHR peptide-based HIV-1 fusion inhibitors. To overcome the limitations of the simplified helix wheel model of six-helix bundle, we herein developed a novel HIV-1 gp41 NHR-CHR-NHR tripartite model for the rational design of HIV-1 fusion inhibitors with improved antiviral activities. DESIGN Based on the crystal structure of six-helix bundle, we evaluated the NHR-binding properties of each residue in CHR. In this new tripartite model, CHR residues were divided into three groups: major binding, nonbinding, and assistant binding sites. METHODS Eight CHR peptides were designed and synthesized to confirm the validity of the tripartite model. Their affinities to NHR and inhibitory activities were analyzed. RESULTS In this tripartite model, replacements in assistant binding sites either increased or decreased the inhibition of HIV-1 infection. We identified three peptides with mutations of the residues in CHR at the assistant binding sites in our tripartite model but nonbinding sites in the helical wheel model. These mutant peptides had anti-HIV-1 activity up to 26-fold more potent than that of C34, a CHR peptide designed on the basis of the helix wheel model. CONCLUSION These data verified the superiority and validity of our new tripartite model for the rational design of HIV-1 fusion inhibitors. This approach can be adapted for designing viral fusion inhibitors against other enveloped viruses with class I membrane fusion protein.
Collapse
|
17
|
Creating an Artificial Tail Anchor as a Novel Strategy To Enhance the Potency of Peptide-Based HIV Fusion Inhibitors. J Virol 2016; 91:JVI.01445-16. [PMID: 27795416 DOI: 10.1128/jvi.01445-16] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/05/2016] [Indexed: 11/20/2022] Open
Abstract
20 (enfuvirtide) and other peptides derived from the human immunodeficiency virus type 1 (HIV-1) gp41 C-terminal heptad repeat (CHR) region inhibit HIV fusion by binding to the hydrophobic grooves on the N-terminal heptad repeat (NHR) trimer and blocking six-helix-bundle (6-HB) formation. Several strategies focusing on the binding grooves of the NHR trimer have been adopted to increase the antiviral activity of the CHR peptides. Here, we developed a novel and simple strategy to greatly enhance the potency of the existing peptide-based HIV fusion inhibitors. First, we identified a shallow pocket adjacent to the groove in the N-terminal region of NHR trimer as a new drug target, and then we designed several short artificial peptides to fit this target. After the addition of IDL (Ile-Asp-Leu) to the C terminus of CHR peptide WQ or MT-WQ, the conjugated peptides, WQ-IDL and MT-WQ-IDL, showed much more potent activities than WQ and T20, respectively, in inhibiting HIV-1 IIIB infection. WQ-IDL and MT-WQ-IDL were also more effective than WQ in blocking HIV-1 Env-mediated membrane fusion and had higher levels of binding affinity with NHR peptide N46. We solved the crystal structure of the 6-HB formed by MT-WQ-IDL and N46 and found that, besides the N-terminal MT hook tail, the IDL tail anchor of MT-WQ-IDL also binds with the shallow hydrophobic pocket outside the groove of the NHR trimer, resulting in enhanced inhibition of HIV-1 fusion with the target cell. It is expected that this novel approach can be widely used to improve the potency of peptidic fusion inhibitors against other enveloped viruses with class I fusion proteins. IMPORTANCE The hydrophobic groove of the human immunodeficiency virus type 1 (HIV-1) gp41 NHR trimer has been known as the classic drug target to develop fusion inhibitors derived from the gp41 CHR. Here, we developed a novel and simple strategy to improve the existing peptide-based HIV fusion inhibitors. We identified a shallow pocket adjacent to the groove in the NHR trimer and added a short artificial peptide consisting of three amino acids (IDL) to the C terminus of a fusion inhibitor to fit this new target. The inhibition activity of this new conjugated peptide was significantly enhanced, by 77-fold, making it much more potent than T20 (enfuvirtide) and suggesting that the IDL tail can be adopted for optimizing existing HIV-1 CHR peptide fusion inhibitors. This new approach of identifying a potential binding pocket outside the traditional target and creating an artificial tail anchor can be widely applied to design novel fusion inhibitors against other class I enveloped viruses, such as Middle East respiratory syndrome coronavirus (MERS-CoV).
Collapse
|
18
|
Becerra JC, Bildstein LS, Gach JS. Recent Insights into the HIV/AIDS Pandemic. MICROBIAL CELL (GRAZ, AUSTRIA) 2016; 3:451-475. [PMID: 28357381 PMCID: PMC5354571 DOI: 10.15698/mic2016.09.529] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/27/2016] [Indexed: 12/21/2022]
Abstract
Etiology, transmission and protection: Transmission of HIV, the causative agent of AIDS, occurs predominantly through bodily fluids. Factors that significantly alter the risk of HIV transmission include male circumcision, condom use, high viral load, and the presence of other sexually transmitted diseases. Pathology/Symptomatology: HIV infects preferentially CD4+ T lymphocytes, and Monocytes. Because of their central role in regulating the immune response, depletion of CD4+ T cells renders the infected individual incapable of adequately responding to microorganisms otherwise inconsequential. Epidemiology, incidence and prevalence: New HIV infections affect predominantly young heterosexual women and homosexual men. While the mortality rates of AIDS related causes have decreased globally in recent years due to the use of highly active antiretroviral therapy (HAART) treatment, a vaccine remains an elusive goal. Treatment and curability: For those afflicted HIV infection remains a serious illness. Nonetheless, the use of advanced therapeutics have transformed a dire scenario into a chronic condition with near average life spans. When to apply those remedies appears to be as important as the remedies themselves. The high rate of HIV replication and the ability to generate variants are central to the viral survival strategy and major barriers to be overcome. Molecular mechanisms of infection: In this review, we assemble new details on the molecular events from the attachment of the virus, to the assembly and release of the viral progeny. Yet, much remains to be learned as understanding of the molecular mechanisms used in viral replication and the measures engaged in the evasion of immune surveillance will be important to develop effective interventions to address the global HIV pandemic.
Collapse
Affiliation(s)
- Juan C. Becerra
- Department of Medicine, Division of Infectious Diseases, University
of California, Irvine, Irvine, CA 92697, USA
| | | | - Johannes S. Gach
- Department of Medicine, Division of Infectious Diseases, University
of California, Irvine, Irvine, CA 92697, USA
| |
Collapse
|
19
|
Abstract
Although the replicative life cycle of HIV within CD4 T cells is understood in molecular detail, less is known about how this human retrovirus promotes the loss of CD4 T lymphocytes. It is this cell death process that drives clinical progression to acquired immune deficiency syndrome (AIDS). Recent studies have highlighted how abortive infection of resting and thus nonpermissive CD4 T cells in lymphoid tissues triggers a lethal innate immune response against the incomplete DNA products generated by inefficient viral reverse transcription in these cells. Sensing of these DNA fragments results in pyroptosis, a highly inflammatory form of programmed cell death, that potentially further perpetuates chronic inflammation and immune activation. As discussed here, these studies cast CD4 T cell death during HIV infection in a different light. Further, they identify drug targets that may be exploited to both block CD4 T cell demise and the chronic inflammatory response generated during pyroptosis.
Collapse
Affiliation(s)
- Gilad Doitsh
- Gladstone Institute of Virology and Immunology, 1650 Owens Street, San Francisco, CA 94158, USA.
| | - Warner C Greene
- Gladstone Institute of Virology and Immunology, 1650 Owens Street, San Francisco, CA 94158, USA; Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA.
| |
Collapse
|
20
|
Wolf G, Greenberg D, Macfarlan TS. Spotting the enemy within: Targeted silencing of foreign DNA in mammalian genomes by the Krüppel-associated box zinc finger protein family. Mob DNA 2015; 6:17. [PMID: 26435754 PMCID: PMC4592553 DOI: 10.1186/s13100-015-0050-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/24/2015] [Indexed: 12/17/2022] Open
Abstract
Tandem C2H2-type zinc finger proteins (ZFPs) constitute the largest transcription factor family in animals. Tandem-ZFPs bind DNA in a sequence-specific manner through arrays of multiple zinc finger domains that allow high flexibility and specificity in target recognition. In tetrapods, a large proportion of tandem-ZFPs contain Krüppel-associated-box (KRAB) repression domains, which are able to induce epigenetic silencing through the KAP1 corepressor. The KRAB-ZFP family continuously amplified in tetrapods through segmental gene duplications, often accompanied by deletions, duplications, and mutations of the zinc finger domains. As a result, tetrapod genomes contain unique sets of KRAB-ZFP genes, consisting of ancient and recently evolved family members. Although several hundred human and mouse KRAB-ZFPs have been identified or predicted, the biological functions of most KRAB-ZFP family members have gone unexplored. Furthermore, the evolutionary forces driving the extraordinary KRAB-ZFP expansion and diversification have remained mysterious for decades. In this review, we highlight recent studies that associate KRAB-ZFPs with the repression of parasitic DNA elements in the mammalian germ line and discuss the hypothesis that the KRAB-ZFP family primarily evolved as an adaptive genomic surveillance system against foreign DNA. Finally, we comment on the computational, genetic, and biochemical challenges of studying KRAB-ZFPs and attempt to predict how these challenges may be soon overcome.
Collapse
Affiliation(s)
- Gernot Wolf
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, MD 20892 USA
| | - David Greenberg
- The Gladstone Institute of Virology and Immunology, University of California, San Francisco, CA 94158 USA ; Present address: Pacific Biosciences, 1380 Willow Road, Menlo Park, CA 94025 USA
| | - Todd S Macfarlan
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, MD 20892 USA
| |
Collapse
|
21
|
Zhang T, Meng X, Zhang T. Global Dynamics of a Virus Dynamical Model with Cell-to-Cell Transmission and Cure Rate. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2015; 2015:758362. [PMID: 26504489 PMCID: PMC4609528 DOI: 10.1155/2015/758362] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 06/30/2015] [Accepted: 07/07/2015] [Indexed: 01/12/2023]
Abstract
The cure effect of a virus model with both cell-to-cell transmission and cell-to-virus transmission is studied. By the method of next generation matrix, the basic reproduction number is obtained. The locally asymptotic stability of the virus-free equilibrium and the endemic equilibrium is considered by investigating the characteristic equation of the model. The globally asymptotic stability of the virus-free equilibrium is proved by constructing suitable Lyapunov function, and the sufficient condition for the globally asymptotic stability of the endemic equilibrium is obtained by constructing suitable Lyapunov function and using LaSalle invariance principal.
Collapse
Affiliation(s)
- Tongqian Zhang
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao 266590, China
- State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China
| | - Xinzhu Meng
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao 266590, China
- State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, China
| | - Tonghua Zhang
- Department of Mathematics, Swinburne University of Technology, P.O. Box 218, Hawthorn, VIC 3122, Australia
| |
Collapse
|
22
|
Galloway NLK, Doitsh G, Monroe KM, Yang Z, Muñoz-Arias I, Levy DN, Greene WC. Cell-to-Cell Transmission of HIV-1 Is Required to Trigger Pyroptotic Death of Lymphoid-Tissue-Derived CD4 T Cells. Cell Rep 2015; 12:1555-1563. [PMID: 26321639 PMCID: PMC4565731 DOI: 10.1016/j.celrep.2015.08.011] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 06/17/2015] [Accepted: 08/04/2015] [Indexed: 12/27/2022] Open
Abstract
The progressive depletion of CD4 T cells underlies clinical progression to AIDS in untreated HIV-infected subjects. Most dying CD4 T cells correspond to resting nonpermissive cells residing in lymphoid tissues. Death is due to an innate immune response against the incomplete cytosolic viral DNA intermediates accumulating in these cells. The viral DNA is detected by the IFI16 sensor, leading to inflammasome assembly, caspase-1 activation, and the induction of pyroptosis, a highly inflammatory form of programmed cell death. We now show that cell-to-cell transmission of HIV is obligatorily required for activation of this death pathway. Cell-free HIV-1 virions, even when added in large quantities, fail to activate pyroptosis. These findings underscore the infected CD4 T cells as the major killing units promoting progression to AIDS and highlight a previously unappreciated role for the virological synapse in HIV pathogenesis.
Collapse
Affiliation(s)
- Nicole LK Galloway
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
| | - Gilad Doitsh
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
| | - Kathryn M. Monroe
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
| | - Zhiyuan Yang
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
| | - Isa Muñoz-Arias
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
| | - David N Levy
- Department of Basic Sciences and Craniofacial Biology, New York
University College of Dentistry, New York, NY, USA
| | - Warner C. Greene
- Gladstone Institute of Virology and Immunology, 1650 Owens Street,
San Francisco, CA 94158
- Department of Medicine, University of California, San Francisco, San
Francisco, CA 94143
- Department of Microbiology and Immunology, University of California,
San Francisco, San Francisco, CA 94143
| |
Collapse
|
23
|
Showa SP, Nyabadza F, Hove-Musekwa SD, Magombedze G. Exploring the benefits of antibody immune response in HIV-1 infection using a discrete model. MATHEMATICAL MEDICINE AND BIOLOGY-A JOURNAL OF THE IMA 2015; 33:189-210. [PMID: 25899531 DOI: 10.1093/imammb/dqv014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 03/31/2015] [Indexed: 02/07/2023]
Abstract
The role of antibodies in HIV-1 infection is investigated using a discrete-time mathematical model that considers cell-free and cell-associated transmission of the virus. Model analysis shows that the effect of each type of antibody is dependent on the stage of the infection. Neutralizing antibodies are efficient in controlling the viral levels in the early days after seroconversion and antibodies that coat HIV-1-infected cells and recruit effector cells to either kill the HIV-1-infected cells or inhibit viral replication are efficient when the infection becomes established. Model simulations show that antibodies that inhibit viral replication are more effective in controlling the infection than those that recruit Natural Killer T cells after infection establishment. The model was fitted to subjects of the Tsedimoso study conducted in Botswana and conclusions similar to elasticity analysis results were obtained. Model fitting results predicted that neutralizing antibodies are more efficient in controlling the viral levels than antibodies that coat HIV-1-infected cells and recruit effector cells to either kill the HIV-1-infected cells or inhibit viral replication in the early days after seroconversion.
Collapse
Affiliation(s)
- S P Showa
- Department of Applied Mathematics, National University of Science and Technology, Box AC 939 Ascot, Bulawayo, Zimbabwe
| | - F Nyabadza
- Department of Mathematical Sciences, University of Stellenbosch, P. Bag XI, Matieland 7602, South Africa
| | - S D Hove-Musekwa
- Department of Applied Mathematics, National University of Science and Technology, Box AC 939 Ascot, Bulawayo, Zimbabwe
| | - G Magombedze
- National Institute for Mathematical and Biological Synthesis, 1122 Volunteer Blvd, University of Tennessee, Knoxville, TN, USA
| |
Collapse
|
24
|
Pathria S, Rolando M, Lieman K, Hayes S, Hardies S, Serwer P. Islands of non-essential genes, including a DNA translocation operon, in the genome of bacteriophage 0305ϕ8-36. BACTERIOPHAGE 2014; 2:25-35. [PMID: 22666654 PMCID: PMC3357382 DOI: 10.4161/bact.19546] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigate genes of lytic, Bacillus thuringiensis bacteriophage 0305ϕ8-36 that are non-essential for laboratory propagation, but might have a function in the wild. We isolate deletion mutants to identify these genes. The non-permutation of the genome (218.948 Kb, with a 6.479 Kb terminal repeat and 247 identified orfs) simplifies isolation of deletion mutants. We find two islands of non-essential genes. The first island (3.01% of the genomic DNA) has an informatically identified DNA translocation operon. Deletion causes no detectable growth defect during propagation in a dilute agarose overlay. Identification of the DNA translocation operon begins with a DNA relaxase and continues with a translocase and membrane-binding anchor proteins. The relaxase is in a family, first identified here, with homologs in other bacteriophages. The second deleted island (3.71% of the genome) has genes for two metallo-protein chaperonins and two tRNAs. Deletion causes a significant growth defect. In addition, (1) we find by "in situ" (in-plaque) single-particle fluorescence microscopy that adsorption to the host occurs at the tip of the 486 nm long tail, (2) we develop a procedure of 0305ϕ8-36 purification that does not cause tail contraction, and (3) we then find by electron microscopy that 0305ϕ8-36 undergoes tail tip-tail tip dimerization that potentially blocks adsorption to host cells, presumably with effectiveness that increases as the bacteriophage particle concentration increases. These observations provide an explanation of the previous observation that 0305ϕ8-36 does not lyse liquid cultures, even though 0305ϕ8-36 is genomically lytic.
Collapse
Affiliation(s)
- Saurav Pathria
- Department of Biochemistry; The University of Texas Health Science Center; San Antonio, TX USA
| | | | | | | | | | | |
Collapse
|
25
|
Showa SP, Nyabadza F, Hove-Musekwa SD, Magombedze G. A comparison of elasticities of viral levels to specific immune response mechanisms in human immunodeficiency virus infection. BMC Res Notes 2014; 7:737. [PMID: 25331717 PMCID: PMC4221687 DOI: 10.1186/1756-0500-7-737] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 10/02/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The presence of an asymptomatic phase in an HIV infection indicates that the immune system can partially control the infection. Determining the immune mechanisms that contribute significantly to the partial control of the infection enhance the HIV infection intervention strategies and is important in vaccine development. Towards this goal, a discrete time HIV model, which incorporates the life cycle aspects of the virus, the antibody (humoral) response and the cell-mediated immune response is formulated to determine immune system components that are most efficient in controlling viral levels. Ecological relationships are used to model the interplay between the immune system components and the HIV pathogen. Model simulations and transient elasticity analysis of the viral levels to immune response parameters are used to compare the different immune mechanisms. RESULTS It is shown that cell-mediated immune response is more effective in controlling the viral levels than the antibody response. Killing of infected cells is shown to be crucial in controlling the viral levels. Our results show a negative correlation between the antibody response and the viral levels in the early stages of the infection, but we predicted this immune mechanism to be positively correlated with the viral levels in the late stage of the infection. A result that suggests lack of relevance of antibody response with infection progression. On the contrary, we predicted the cell-mediated immune response to be always negatively correlated with viral levels. CONCLUSION Neutralizing antibodies can only control the viral levels in the early days of the HIV infection whereas cell-mediated immune response is beneficial during all the stages of the infection. This study predicts that vaccine design efforts should also focus on stimulating killer T cells that target infected cells.
Collapse
Affiliation(s)
- Sarudzai P Showa
- Department of Applied Mathematics, National University of Science and Technology, P,O, Box AC 939 Ascot, Bulawayo, Zimbabwe.
| | | | | | | |
Collapse
|
26
|
Abstract
This review outlines how mathematical models have been helpful, and continue to be so, for obtaining insights into the in vivo dynamics of HIV infection. The review starts with a discussion of a basic mathematical model that has been frequently used to study HIV dynamics. Some crucial results are described, including the estimation of key parameters that characterize the infection, and the generation of influential theories which argued that in vivo virus evolution is a key player in HIV pathogenesis. Subsequently, more recent concepts are reviewed that have relevance for disease progression, including the multiple infection of cells and the direct cell-to-cell transmission of the virus through the formation of virological synapses. These are important mechanisms that can influence the rate at which HIV spreads through its target cell population, which is tightly linked to the rate at which the disease progresses towards AIDS.
Collapse
Affiliation(s)
- Dominik Wodarz
- Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA, 926967, USA,
| |
Collapse
|
27
|
Titanji BK, Aasa-Chapman M, Pillay D, Jolly C. Protease inhibitors effectively block cell-to-cell spread of HIV-1 between T cells. Retrovirology 2013; 10:161. [PMID: 24364896 PMCID: PMC3877983 DOI: 10.1186/1742-4690-10-161] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/11/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Human Immunodeficiency Virus type-1 (HIV-1) spreads by cell-free diffusion and by direct cell-to-cell transfer, the latter being a significantly more efficient mode of transmission. Recently it has been suggested that cell-to-cell spread may permit ongoing virus replication in the presence of antiretroviral therapy (ART) based on studies performed using Reverse Transcriptase Inhibitors (RTIs). Protease Inhibitors (PIs) constitute an important component of ART; however whether this class of inhibitors can suppress cell-to-cell transfer of HIV-1 is unexplored. Here we have evaluated the inhibitory effect of PIs during cell-to-cell spread of HIV-1 between T lymphocytes. RESULTS Using quantitative assays in cell line and primary cell systems that directly measure the early steps of HIV-1 infection we find that the PIs Lopinavir and Darunavir are equally potent against both cell-free and cell-to-cell spread of HIV-1. We further show that a protease resistant mutant maintains its resistant phenotype during cell-to-cell spread and is transmitted more efficiently than wild-type virus in the presence of drug. By contrast we find that T cell-T cell spread of HIV-1 is 4-20 fold more resistant to inhibition by the RTIs Nevirapine, Zidovudine and Tenofovir. Notably, varying the ratio of infected and uninfected cells in co-culture impacted on the degree of inhibition, indicating that the relative efficacy of ART is dependent on the multiplicity of infection. CONCLUSIONS We conclude that if the variable effects of antiviral drugs on cell-to-cell virus dissemination of HIV-1 do indeed impact on viral replication and maintenance of viral reservoirs this is likely to be influenced by the antiviral drug class, since PIs appear particularly effective against both modes of HIV-1 spread.
Collapse
Affiliation(s)
| | | | | | - Clare Jolly
- Division of Infection and Immunity, University College London, Cruciform Building, Gower St, London WC1E 6BT, United Kingdom.
| |
Collapse
|
28
|
Salmons B, Gunzburg WH. Revisiting a role for a mammary tumor retrovirus in human breast cancer. Int J Cancer 2013; 133:1530-5. [DOI: 10.1002/ijc.28210] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 04/09/2013] [Indexed: 12/12/2022]
Affiliation(s)
- Brian Salmons
- SG Austria; 20 Biopolis Way #05-518 Centros; Singapore; Singapore
| | - Walter H. Gunzburg
- Institute of Virology; Department of Pathobiology; University of Veterinary Medicine; Vienna; Austria
| |
Collapse
|
29
|
Komarova NL, Anghelina D, Voznesensky I, Trinité B, Levy DN, Wodarz D. Relative contribution of free-virus and synaptic transmission to the spread of HIV-1 through target cell populations. Biol Lett 2012; 9:20121049. [PMID: 23269844 DOI: 10.1098/rsbl.2012.1049] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Human immunodeficiency virus can spread through target cells by transmission of cell-free virus or directly from cell-to-cell via formation of virological synapses. Although cell-to-cell transmission has been described as much more efficient than cell-free infection, the relative contribution of the two transmission pathways to virus growth during multiple rounds of replication remains poorly defined. Here, we fit a mathematical model to previously published and newly generated in vitro data, and determine that free-virus and synaptic transmission contribute approximately equally to the growth of the virus population.
Collapse
Affiliation(s)
- Natalia L Komarova
- Department of Mathematics, University of California, Irvine, CA 92697, USA
| | | | | | | | | | | |
Collapse
|
30
|
Innate immune recognition of HIV-1. Immunity 2012; 37:389-98. [PMID: 22999945 DOI: 10.1016/j.immuni.2012.08.011] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 08/21/2012] [Accepted: 08/24/2012] [Indexed: 02/01/2023]
Abstract
In contrast to the extraordinary body of knowledge gained over the past three decades on the virology, pathogenesis, and immunology of HIV-1 infection, innate sensors that detect HIV-1 had remained elusive until recently. By virtue of integration, retroviridae makes up a substantial portion of our genome. Thus, immune strategies that deal with endogenous retroviruses are, by necessity, those of self-preservation and not of virus elimination. Some of the principles of such strategies may also apply for defense against exogenous retroviruses including HIV-1. Here, I highlight several sensors that have recently been revealed to be capable of recognizing distinct features of HIV-1 infection, while taking into account the host-retrovirus relationship that converges on avoiding pathogenic inflammatory consequences.
Collapse
|
31
|
Komarova NL, Levy DN, Wodarz D. Effect of synaptic transmission on viral fitness in HIV infection. PLoS One 2012; 7:e48361. [PMID: 23166585 PMCID: PMC3499495 DOI: 10.1371/journal.pone.0048361] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 09/24/2012] [Indexed: 11/19/2022] Open
Abstract
HIV can spread through its target cell population either via cell-free transmission, or by cell-to-cell transmission, presumably through virological synapses. Synaptic transmission entails the transfer of tens to hundreds of viruses per synapse, a fraction of which successfully integrate into the target cell genome. It is currently not understood how synaptic transmission affects viral fitness. Using a mathematical model, we investigate how different synaptic transmission strategies, defined by the number of viruses passed per synapse, influence the basic reproductive ratio of the virus, R(0), and virus load. In the most basic scenario, the model suggests that R(0) is maximized if a single virus particle is transferred per synapse. R(0) decreases and the infection eventually cannot be maintained for larger numbers of transferred viruses, because multiple infection of the same cell wastes viruses that could otherwise enter uninfected cells. To explain the relatively large number of HIV copies transferred per synapse, we consider additional biological assumptions under which an intermediate number of viruses transferred per synapse could maximize R(0). These include an increased burst size in multiply infected cells, the saturation of anti-viral factors upon infection of cells, and rate limiting steps during the process of synapse formation.
Collapse
Affiliation(s)
- Natalia L. Komarova
- Department of Mathematics, University of California Irvine, Irvine, California, United States of America
- Department of Ecology and Evolution, University of California Irvine, Irvine, California, United States of America
- * E-mail: (NLK); (DW)
| | - David N. Levy
- Department of Basic Science, New York University College of Dentistry, New York, New York, United States of America
| | - Dominik Wodarz
- Department of Mathematics, University of California Irvine, Irvine, California, United States of America
- Department of Ecology and Evolution, University of California Irvine, Irvine, California, United States of America
- * E-mail: (NLK); (DW)
| |
Collapse
|
32
|
Logg CR, Robbins JM, Jolly DJ, Gruber HE, Kasahara N. Retroviral replicating vectors in cancer. Methods Enzymol 2012; 507:199-228. [PMID: 22365776 DOI: 10.1016/b978-0-12-386509-0.00011-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The use of replication-competent viruses for the treatment of cancer is an emerging technology that shows significant promise. Among the various different types of viruses currently being developed as oncolytic agents, retroviral replicating vectors (RRVs) possess unique characteristics that allow highly efficient, non-lytic, and tumor-selective gene transfer. By retaining all of the elements necessary for viral replication, RRVs are capable of transmitting genes via exponential in situ amplification. Their replication-competence also provides a powerful means whereby novel and useful RRV variants can be generated using natural selection. Their stringent requirement for cell division in order to achieve productive infection, and their preferential replication in cells with defective innate immunity, confer a considerable degree of natural specificity for tumors. Furthermore, their ability to integrate stably into the genome of cancer cells, without immediate cytolysis, contributes to long-lasting therapeutic efficacy. Thus, RRVs show much promise as therapeutic agents for cancer and are currently being tested in the clinic. Here we describe experimental methods for their production and quantitation, for adaptive evolution and natural selection to develop novel or improved RRV, and for in vitro and in vivo assessment of the therapeutic efficacy of RRVs carrying prodrug activator genes for treatment of cancer.
Collapse
Affiliation(s)
- Christopher R Logg
- Department of Medicine, University of California, Los Angeles, California, USA
| | | | | | | | | |
Collapse
|
33
|
Chopy D, Detje CN, Lafage M, Kalinke U, Lafon M. The type I interferon response bridles rabies virus infection and reduces pathogenicity. J Neurovirol 2011; 17:353-67. [PMID: 21805057 DOI: 10.1007/s13365-011-0041-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 05/25/2011] [Accepted: 06/10/2011] [Indexed: 12/24/2022]
Abstract
Rabies virus (RABV) is a neurotropic virus transmitted by the bite of an infected animal that triggers a fatal encephalomyelitis. During its migration in the nervous system (NS), RABV triggers an innate immune response, including a type I IFN response well known to limit viral infections. We showed that although the neuroinvasive RABV strain CVS-NIV dampens type I IFN signaling by inhibiting IRF3 phosphorylation and STAT2 translocation, an early and transient type I IFN response is still triggered in the infected neuronal cells and NS. This urged us to investigate the role of type I IFN on RABV infection. We showed that primary mouse neurons (DRGs) of type I IFN(α/β) receptor deficient mice (IFNAR(-/-) mice) were more susceptible to RABV than DRGs of WT mice. In addition, exogenous type I IFN is partially efficient in preventing and slowing down infection in human neuroblastoma cells. Intra-muscular inoculation of type I IFNAR deficient mice [IFNAR(-/-) mice and NesCre ((+/-)) IFNAR ((flox/flox)) mice lacking IFNAR in neural cells of neuroectodermal origin only] with RABV reveals that the type I IFN response limits RABV dissemination in the inoculated muscle, slows down invasion of the spinal cord, and delays mortality. Thus, the type I IFN which is still produced in the NS during RABV infection is efficient enough to reduce neuroinvasiveness and pathogenicity and partially protect the host from fatal infection.
Collapse
Affiliation(s)
- Damien Chopy
- Département de Virologie Institut Pasteur, Unité de Neuroimmunologie Virale, 75015, Paris, France
| | | | | | | | | |
Collapse
|