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Pu J, Wang Q, Xu W, Lu L, Jiang S. Development of Protein- and Peptide-Based HIV Entry Inhibitors Targeting gp120 or gp41. Viruses 2019; 11:v11080705. [PMID: 31374953 PMCID: PMC6722851 DOI: 10.3390/v11080705] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 07/26/2019] [Accepted: 07/26/2019] [Indexed: 01/08/2023] Open
Abstract
Application of highly active antiretroviral drugs (ARDs) effectively reduces morbidity and mortality in HIV-infected individuals. However, the emergence of multiple drug-resistant strains has led to the increased failure of ARDs, thus calling for the development of anti-HIV drugs with targets or mechanisms of action different from those of the current ARDs. The first peptide-based HIV entry inhibitor, enfuvirtide, was approved by the U.S. FDA in 2003 for treatment of HIV/AIDS patients who have failed to respond to the current ARDs, which has stimulated the development of several series of protein- and peptide-based HIV entry inhibitors in preclinical and clinical studies. In this review, we highlighted the properties and mechanisms of action for those promising protein- and peptide-based HIV entry inhibitors targeting the HIV-1 gp120 or gp41 and discussed their advantages and disadvantages, compared with the current ARDs.
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Affiliation(s)
- Jing Pu
- Shanghai Public Health Clinical Center and School of Basic Medical Sciences, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Fudan University, Shanghai 200032, China
| | - Qian Wang
- Shanghai Public Health Clinical Center and School of Basic Medical Sciences, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Fudan University, Shanghai 200032, China
| | - Wei Xu
- Shanghai Public Health Clinical Center and School of Basic Medical Sciences, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Fudan University, Shanghai 200032, China
| | - Lu Lu
- Shanghai Public Health Clinical Center and School of Basic Medical Sciences, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Fudan University, Shanghai 200032, China.
| | - Shibo Jiang
- Shanghai Public Health Clinical Center and School of Basic Medical Sciences, Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), Fudan University, Shanghai 200032, China.
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
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Kuhlmann AS, Haworth KG, Barber-Axthelm IM, Ironside C, Giese MA, Peterson CW, Kiem HP. Long-Term Persistence of Anti-HIV Broadly Neutralizing Antibody-Secreting Hematopoietic Cells in Humanized Mice. Mol Ther 2018; 27:164-177. [PMID: 30391142 DOI: 10.1016/j.ymthe.2018.09.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 09/14/2018] [Accepted: 09/20/2018] [Indexed: 01/12/2023] Open
Abstract
Broadly neutralizing antibodies (bNAbs) are among the most promising strategies to achieve long-term control of HIV-1 in the absence of combination antiretroviral therapy. Passive administration of such antibodies in patients efficiently decreases HIV-1 viremia, but is limited by the serum half-life of the protein. Here, we investigated whether antibody-secreting hematopoietic cells could overcome this problem. We genetically modified human CD34+ hematopoietic stem and progenitor cells (HSPCs) to secrete bNAbs and transplanted them into immunodeficient mice. We found that the gene-modified cells engraft and stably secrete antibodies in the peripheral blood of the animals for the 9 months of the study. Antibodies were predominantly expressed by human HSPC-derived T- and B cells. Importantly, we found that secreted PGT128 was able to delay HIV-1 viremia in vivo and also prevent a decline in CD4+ cells. Gene-modified cells were maintained in bone marrow and were also detected in spleen, thymus, lymph nodes, and gut-associated lymphoid tissue. These data indicate that the bNAb secretion from HSPC-derived cells in mice is functional and can affect viral infection and CD4+ cell maintenance. This study paves the way for potential applications to other diseases requiring long-lasting protein or antibody delivery.
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Affiliation(s)
- Anne-Sophie Kuhlmann
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA
| | - Kevin G Haworth
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA
| | - Isaac M Barber-Axthelm
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA
| | - Christina Ironside
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA
| | - Morgan A Giese
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA
| | - Christopher W Peterson
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA; Department of Medicine, University of Washington, Seattle, WA, 98195, USA
| | - Hans-Peter Kiem
- Stem Cell and Gene Therapy Program, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109-1024, USA; Department of Medicine, University of Washington, Seattle, WA, 98195, USA; Department of Pathology, University of Washington, Seattle, WA, 98195, USA.
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3
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Focosi D, Maggi F, Ceccherini-Nelli L, Pistello M. Cell therapies for treatment of human immunodeficiency virus infection. Rev Med Virol 2015; 25:156-74. [PMID: 25727480 DOI: 10.1002/rmv.1831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/30/2015] [Accepted: 02/05/2015] [Indexed: 12/15/2022]
Abstract
After the serendipitous discovery of HIV eradication in the "Berlin patient", interest has grown in curing HIV infection by replacing the patient's replication-competent blood cells with infection-resistant ones. At the same time, induced pluripotent stem cell technologies and genetic engineering have boosted cell therapy transfer into the clinic. Currently available cell therapy approaches to attempt to cure HIV infection include the following: (1) Transplantation of autologous or allogeneic cells spontaneously resistant or edited to resist HIV infection; (2) Transplantation of autologous T-lymphocytes spontaneously targeting or redirected against HIV; and (3) Transplantation of autologous cells engineered to work as anti-HIV antibody factories. We review here the preliminary results and potential for future applications of these approaches.
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Affiliation(s)
- Daniele Focosi
- Retrovirus Center and Virology Section, Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, Italy
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Abstract
The use of antibodies as a treatment for disease has it origins in experiments performed in the 1890s, and since these initial experiments, monoclonal antibodies (mAbs) have become one of the fastest growing therapeutic classes for the treatment of cancer, autoimmune disease, and infectious diseases. However, treatment with therapeutic mAbs often requires high doses given via long infusions or multiple injections, which, coupled with the prohibitively high cost associated with the production of clinical-grade proteins and the transient serum half-lives that necessitate multiple administrations to gain therapeutic benefits, makes large-scale treatment of patients, especially patients in the developing world, difficult. Due to their low-cost and rapid scalability, nucleic acid-based approaches to deliver antibody gene sequences for in situ mAb production have gained substantial traction. In this review, we discuss new approaches to produce therapeutic mAbs in situ to overcome the need for the passive infusion of purified protein.
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Affiliation(s)
- Todd J Suscovich
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
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5
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Brimijoin S, Shen X, Orson F, Kosten T. Prospects, promise and problems on the road to effective vaccines and related therapies for substance abuse. Expert Rev Vaccines 2013; 12:323-32. [PMID: 23496671 DOI: 10.1586/erv.13.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This review addresses potential new treatments for stimulant drugs of abuse, especially cocaine. Clinical trials of vaccines against cocaine and nicotine have been completed with the generally encouraging result that subjects showing high titers of antidrug antibody experience a reduction in drug reward, which may aid in cessation. New vaccine technologies, including gene transfer of highly optimized monoclonal antibodies, are likely to improve such outcomes further. In the special case of cocaine abuse, a metabolic enzyme is emerging as an alternative or added therapeutic intervention, which would also involve gene transfer. Such approaches still require extensive studies of safety and efficacy, but they may eventually contribute to a robust form of in vivo drug interception that greatly reduces the risks of addiction relapse.
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Affiliation(s)
- Stephen Brimijoin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, USA.
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Egerer L, Volk A, Kahle J, Kimpel J, Brauer F, Hermann FG, von Laer D. Secreted antiviral entry inhibitory (SAVE) peptides for gene therapy of HIV infection. Mol Ther 2011; 19:1236-44. [PMID: 21364540 DOI: 10.1038/mt.2011.30] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Gene therapeutic strategies for human immunodeficiency virus type 1 (HIV-1) infection could potentially overcome the limitations of standard antiretroviral drug therapy (ART). However, in none of the clinical gene therapy trials published to date, therapeutic levels of genetic protection have been achieved in the target cell population for HIV-1. To improve systemic antiviral efficacy, C peptides, which are efficient inhibitors of HIV-1 entry, were engineered for high-level secretion by genetically modified cells. The size restrictions for efficient peptide export through the secretory pathway were overcome by expressing the C peptides as concatemers, which were processed into monomers by furin protease cleavage. These secreted antiviral entry inhibitory (SAVE) peptides mediated a substantial protective bystander effect on neighboring nonmodified cells, thus suppressing virus replication even if only a small fraction of cells was genetically modified. Accordingly, these SAVE peptides may provide a strong benefit to AIDS patients in future, and, if applied by direct in vivo gene delivery, could present an effective alternative to antiretroviral drug regimen.
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Affiliation(s)
- Lisa Egerer
- Department of Hygiene, Microbiology and Social Medicine, Division of Virology, Innsbruck Medical University, Innsbruck, Austria.
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Inhibition of in vivo HIV infection in humanized mice by gene therapy of human hematopoietic stem cells with a lentiviral vector encoding a broadly neutralizing anti-HIV antibody. J Virol 2010; 84:6645-53. [PMID: 20410262 DOI: 10.1128/jvi.02339-09] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Due to the inherent immune evasion properties of the HIV envelope, broadly neutralizing HIV-specific antibodies capable of suppressing HIV infection are rarely produced by infected individuals. We examined the feasibility of utilizing genetic engineering to circumvent the restricted capacity of individuals to endogenously produce broadly neutralizing HIV-specific antibodies. We constructed a single lentiviral vector that encoded the heavy and light chains of 2G12, a broadly neutralizing anti-HIV human antibody, and that efficiently transduced and directed primary human B cells to secrete 2G12. To evaluate the capacity of this approach to provide protection from in vivo HIV infection, we used the humanized NOD/SCID/gamma(c)(null) mouse model, which becomes populated with human B cells, T cells, and macrophages after transplantation with human hematopoietic stem cells (hu-HSC) and develops in vivo infection after inoculation with HIV. The plasma of the irradiated NOD/SCID/gamma(c)(null) mice transplanted with hu-HSC transduced with the 2G12-encoding lentivirus contained 2G12 antibody, likely secreted by progeny human lymphoid and/or myeloid cells. After intraperitoneal inoculation with high-titer HIV-1(JR-CSF), mice engrafted with 2G12-transduced hu-HSC displayed marked inhibition of in vivo HIV infection as manifested by a profound 70-fold reduction in plasma HIV RNA levels and an almost 200-fold reduction in HIV-infected human cell numbers in mouse spleens, compared to control hu-HSC-transplanted NOD/SCID/gamma(c)(null) mice inoculated with equivalent high-titer HIV-1(JR-CSF). These results support the potential efficacy of this new gene therapy approach of using lentiviral vectors encoding a mixture of broadly neutralizing HIV antibodies for the treatment of HIV infection, particularly infection with multiple-drug-resistant isolates.
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8
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Broadly neutralizing monoclonal antibodies 2F5 and 4E10 directed against the human immunodeficiency virus type 1 gp41 membrane-proximal external region protect against mucosal challenge by simian-human immunodeficiency virus SHIVBa-L. J Virol 2009; 84:1302-13. [PMID: 19906907 DOI: 10.1128/jvi.01272-09] [Citation(s) in RCA: 273] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The membrane-proximal external region (MPER) of HIV-1, located at the C terminus of the gp41 ectodomain, is conserved and crucial for viral fusion. Three broadly neutralizing monoclonal antibodies (bnMAbs), 2F5, 4E10, and Z13e1, are directed against linear epitopes mapped to the MPER, making this conserved region an important potential vaccine target. However, no MPER antibodies have been definitively shown to provide protection against HIV challenge. Here, we show that both MAbs 2F5 and 4E10 can provide complete protection against mucosal simian-human immunodeficiency virus (SHIV) challenge in macaques. MAb 2F5 or 4E10 was administered intravenously at 50 mg/kg to groups of six male Indian rhesus macaques 1 day prior to and again 1 day following intrarectal challenge with SHIV(Ba-L). In both groups, five out of six animals showed complete protection and sterilizing immunity, while for one animal in each group a low level of viral replication following challenge could not be ruled out. The study confirms the protective potential of 2F5 and 4E10 and supports emphasis on HIV immunogen design based on the MPER region of gp41.
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Johnson PR, Schnepp BC, Zhang J, Connell MJ, Greene SM, Yuste E, Desrosiers RC, Clark KR. Vector-mediated gene transfer engenders long-lived neutralizing activity and protection against SIV infection in monkeys. Nat Med 2009; 15:901-6. [PMID: 19448633 PMCID: PMC2723177 DOI: 10.1038/nm.1967] [Citation(s) in RCA: 251] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 04/11/2009] [Indexed: 12/24/2022]
Abstract
The holy grail for HIV vaccine development is an immunogen that elicits persisting antibodies with broad neutralizing activity against field strains of the virus. Unfortunately, very little progress has been made in finding or designing such immunogens. Using the SIV model, we have taken a markedly different approach: delivery of an adeno-associated virus (AAV) gene transfer vector to muscle for the expression of antibodies or antibody-like immunoadhesins having predetermined anti-SIV specificity. With this approach, anti-SIV molecules are endogenously synthesized in myofibers and passively distributed to the circulatory system. Using such an approach in monkeys, we have now generated long-lasting neutralizing activity in serum and observed complete protection against intravenous challenge with virulent SIV. In essence, this strategy bypasses the adaptive immune system and holds significant promise as a novel approach to an effective HIV vaccine.
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Affiliation(s)
- Philip R Johnson
- The Children's Hospital of Philadelphia and the University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA.
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Abstract
This chapter describes the major gene therapeutic approaches for viral infections. The vast majority of published approaches target severe chronic viral infections such as hepatitis B or C and HIV infection. Two basic gene therapy strategies are introduced here. The first involves the expression of a protein or an RNA that inhibits viral replication by targeting crucial steps of the viral life cycle or by interfering with a cellular factor required for virus replication. The major limitation of this approach is that primary levels of gene modification have generally not been sufficient to reduce the availability of target cells permissive for virus replication to a level that significantly decreases overall viral load. Thus, investigators have banked on the expectation that gene-protected cells have a sufficient selective advantage to accumulate and gain prevalence over time, a prediction that so far could not be confirmed in clinical trials. In vivo levels of gene modification can be improved, however, by introducing an additional selectable marker. In addition, a secreted antiviral gene product that exerts a bystander effect could significantly reduce overall virus replication despite relatively low levels of gene modification. In addition to these direct antiviral approaches, several strategies have been developed that employ or aim to enhance host immune responses. The innate immune response has been enhanced, for example, by the in vivo expression of interferons. Alternatively, T cells can be grafted with recombinant receptors to boost adaptive virus-specific immunity. These approaches are especially promising for chronic virus infection, where natural immune responses are evidently not sufficient to effectively control virus replication.
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11
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von Laer D, Hasselmann S, Hasselmann K. Gene therapy for HIV infection: what does it need to make it work? J Gene Med 2006; 8:658-67. [PMID: 16598816 DOI: 10.1002/jgm.908] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The efficacy of antiviral drug therapy for HIV infection is limited by toxicity and viral resistance. Thus, alternative therapies need to be explored. Several gene therapeutic strategies for HIV infection have been developed, but in clinical testing therapeutically effective levels of the transgene product were not achieved. This review focuses on the determinants of therapeutic efficacy and discusses the potential and also the limits of current gene therapy approaches for HIV infection.
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Affiliation(s)
- Dorothee von Laer
- Georg-Speyer-Haus, Paul-Ehrlich-Strasse 42, Frankfurt a.M., Germany.
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Pincus SH, Fang H, Wilkinson RA, Olson WC, Marcotte TK. A modified SCID mouse model of HIV infection with utility for testing anti-HIV therapies. AIDS Res Hum Retroviruses 2003; 19:901-8. [PMID: 14585222 DOI: 10.1089/088922203322493076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Using human tumor cells we have developed a mouse model of active HIV infection that may be used for testing antiviral agents, although it does not reflect the pathogenesis of human infection. Irradiated SCID/NOD mice are injected with a tumor of human CD4+ lymphoma cells susceptible to infection and at a separate site, tumor cells persistently infected with either primary or T cell line-adapted strains of HIV. The spread of infection from the infected to the susceptible tumor is monitored as plasma p24 and the presence of HIV-infected cells in the spleen. We have used this model to examine the relative efficacy of neutralizing anti-HIV antibodies to halt the spread of infection. We have found that the tetrameric CD4-antibody fusion protein, CD4-IgG2, is highly effective compared to an anti-V3 loop antibody. This animal model, while not replicating the human disease, allows for the simultaneous testing of efficacy, toxicity, and pharmacokinetics of potential new antiviral therapies. The model can easily be powered to enable comparisons between different therapeutic agents and dosing regimens.
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Affiliation(s)
- Seth H Pincus
- Department of Microbiology, Montana State University, Bozeman, MT 59717, USA.
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Baumeister MA, Chattergoon MA, Weiner DB. Prospects for an HIV vaccine: conventional approaches and DNA immunization. Biotechnol Genet Eng Rev 2003; 19:205-42. [PMID: 12520879 DOI: 10.1080/02648725.2002.10648030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Mark A Baumeister
- University of Pennsylvania School of Medicine, Department of Pathology and Laboratory Medicine, 505 Stellar-Chance Laboratories, 422 Curie Blvd., Philadelphia, PA 19104, USA
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Pincus SH, Fang H, Wilkinson RA, Marcotte TK, Robinson JE, Olson WC. In vivo efficacy of anti-glycoprotein 41, but not anti-glycoprotein 120, immunotoxins in a mouse model of HIV infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:2236-41. [PMID: 12574398 DOI: 10.4049/jimmunol.170.4.2236] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Immunotoxins (ITs) targeting the HIV envelope protein are among the most efficacious antiviral therapies when tested in vitro. Yet a first-generation IT targeted to gp120, CD4-PE40 (chimeric immunotoxin using CD4 and the translocation and enzymatic domains of Pseudomonas exotoxin A), showed limited promise in initial clinical testing, highlighting the need for improved ITs. We have used a new mouse model of HIV infection to test the comparative efficacy of anti-HIV ITs targeted to gp120 or to gp41. Irradiated SCID/nonobese diabetic mice are injected with a tumor of human CD4(+) cells susceptible to infection and at a separate site persistently HIV-infected cells. The spread of infection from infected to susceptible tumor is monitored by plasma p24 and the presence of HIV-infected cells in the spleen. Anti-gp41 ITs in combination with tetrameric CD4-human Ig fusion protein have pronounced anti-HIV effects. Little if any anti-HIV efficacy was found with either CD4-PE40 or an Ab-targeted anti-gp120 IT. These data support continued exploration of the utility of ITs for HIV infection, particularly the use of anti-gp41 ITs in combination with soluble CD4 derivatives.
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MESH Headings
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/pharmacokinetics
- Antibodies, Monoclonal/therapeutic use
- Antibodies, Viral/administration & dosage
- Antibodies, Viral/therapeutic use
- CD4 Immunoadhesins/administration & dosage
- CD4 Immunoadhesins/therapeutic use
- Disease Models, Animal
- Drug Therapy, Combination
- HIV Envelope Protein gp120/immunology
- HIV Envelope Protein gp41/immunology
- HIV Infections/immunology
- HIV Infections/prevention & control
- HIV Infections/virology
- HIV-1/immunology
- HeLa Cells
- Humans
- Immunotoxins/administration & dosage
- Immunotoxins/pharmacokinetics
- Immunotoxins/therapeutic use
- Injections, Intraperitoneal
- Mice
- Mice, Inbred NOD
- Mice, SCID
- Ricin/administration & dosage
- Ricin/pharmacokinetics
- Ricin/therapeutic use
- Tumor Cells, Cultured
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Affiliation(s)
- Seth H Pincus
- Department of Microbiology and Animal Resources Center, Montana State University, Bozeman, MT 59717, USA.
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