scholarly journals Activity of a Novel Combined Antiretroviral Therapy of Gemcitabine and Decitabine in a Mouse Model for HIV-1

2012 ◽  
Vol 56 (4) ◽  
pp. 1942-1948 ◽  
Author(s):  
Christine L. Clouser ◽  
Colleen M. Holtz ◽  
Mary Mullett ◽  
Daune L. Crankshaw ◽  
Jacquie E. Briggs ◽  
...  

ABSTRACTThe emergence of drug resistance threatens to limit the use of current anti-HIV-1 drugs and highlights the need to expand the number of treatment options available for HIV-1-infected individuals. Our previous studies demonstrated that two clinically approved drugs, decitabine and gemcitabine, potently inhibited HIV-1 replication in cell culture through a mechanism that is distinct from the mechanisms for the drugs currently used to treat HIV-1 infection. We further demonstrated that gemcitabine inhibited replication of a related retrovirus, murine leukemia virus (MuLV),in vivousing the MuLV-based LP-BM5/murine AIDS (MAIDS) mouse model at doses that were not toxic. Since decitabine and gemcitabine inhibited MuLV and HIV-1 replication with similar potency in cell culture, the current study examined the efficacy and toxicity of the drug combination using the MAIDS model. The data demonstrate that the drug combination inhibited disease progression, as detected by histopathology, viral loads, and spleen weights, at doses lower than those that would be required if the drugs were used individually. The combination of decitabine and gemcitabine exerted antiviral activity at doses that were not toxic. These findings indicate that the combination of decitabine and gemcitabine shows potent antiretroviral activity at nontoxic doses and should be further investigated for clinical relevance.

2000 ◽  
Vol 74 (20) ◽  
pp. 9525-9531 ◽  
Author(s):  
Louis M. Mansky

ABSTRACT Several studies have indicated that the genetic diversity of human T-cell leukemia virus type 1 (HTLV-1), a virus associated with adult T-cell leukemia, is significantly lower than that of other retroviruses, including that of human immunodeficiency virus type 1 (HIV-1). To test whether HTLV-1 variation is lower than other retroviruses, a tractable vector system has been developed to measure reverse transcription accuracy in one round of HTLV-1 replication. This system consists of a HTLV-1 vector that contains a cassette with the neomycin phosphotransferase (neo) gene, a bacterial origin of DNA replication, and the lacZα peptide gene region (the mutational target). The vector was replicated bytrans-complementation with helper plasmids. The in vivo mutation rate for HTLV-1 was determined to be 7 × 10−6 mutations per target base pair per replication cycle. The majority of the mutations identified were base substitution mutations, namely, G-to-A and C-to-T transitions, frameshift mutations, and deletion mutations. Mutation of the methionine residue in the conserved YMDD motif of the HTLV-1 reverse transcriptase to either alanine or valine (i.e., M188A or M188V) led to a factor of two increase in the rate of mutation, indicating the role of this motif in enzyme accuracy. The HTLV-1 in vivo mutation rate is comparable to that of bovine leukemia virus (BLV), another member of the HTLV/BLV genus of retroviruses, and is about fourfold lower than that of HIV-1. These observations indicate that while the mutation rate of HTLV-1 is significantly lower than HIV-1, this lower rate alone would not explain the low diversity in HTLV-1 isolates, supporting the hypothesis that HTLV-1 replicates primarily as a provirus during cellular DNA replication rather than as a virus via reverse transcription.


Author(s):  
Courtney L. Finch ◽  
Julie Dyall ◽  
Shuang Xu ◽  
Elizabeth A. Nelson ◽  
Elena Postnikova ◽  
...  

Outbreaks of Ebola ebolavirus (EBOV) have been associated with high morbidity and mortality. Milestones have been reached recently in the management of EBOV disease (EVD) with licensure of an EBOV vaccine and two monoclonal antibody therapies. However, neither vaccines nor therapies are available for other disease-causing filoviruses. In preparation for such outbreaks, and for more facile and cost-effective management of EVD, we seek a cocktail containing orally available and room temperature stable drugs with strong activity against multiple filoviruses. We previously showed that (bepridil + sertraline) and (sertraline + toremifene) synergistically suppress EBOV in cell cultures. Here we describe steps towards testing these combinations in a mouse model of EVD. We identified a vehicle suitable for oral delivery of the component drugs and determined that, thus formulated the drugs are equally active against EBOV as preparations in DMSO, and they maintain activity upon storage in solution for up to seven days. Pharmacokinetic (PK) studies indicated that the drugs in the oral delivery vehicle are well tolerated in mice at the highest doses tested. Collectively the data support advancement of these combinations to tests for synergy in a mouse model of EVD. Moreover, mathematical modeling based on human oral PK projects that the combinations would be more active in humans than their component single drugs.


2004 ◽  
Vol 78 (3) ◽  
pp. 1219-1229 ◽  
Author(s):  
Xian-Yang Zhang ◽  
Vincent F. La Russa ◽  
Jakob Reiser

ABSTRACT Bone-marrow-derived mesenchymal stem cells (MSCs) have attracted considerable attention as tools for the systemic delivery of therapeutic proteins in vivo, and the ability to efficiently transfer genes of interest into such cells would create a number of therapeutic opportunities. We have designed and tested a series of human immunodeficiency virus type 1 (HIV-1)-based vectors and vectors based on the oncogenic murine stem cell virus to deliver and express transgenes in human MSCs. These vectors were pseudotyped with either the vesicular stomatitis virus G (VSV-G) glycoprotein (GP) or the feline endogenous virus RD114 envelope GP. Transduction efficiencies and transgene expression levels in MSCs were analyzed by quantitative flow cytometry and quantitative real-time PCR. While transduction efficiencies with virus particles pseudotyped with the VSV-G GP were found to be high, RD114 pseudotypes revealed transduction efficiencies that were 1 to 2 orders of magnitude below those observed with VSV-G pseudotypes. However, chimeric RD114 GPs, with the transmembrane and extracellular domains fused to the cytoplasmic domain derived from the amphotropic Moloney murine leukemia virus 4070A GP, revealed about 15-fold higher titers relative to the unmodified RD114 GP. The transduction efficiencies in human MSCs of HIV-1-based vectors pseudotyped with the chimeric RD114 GP were similar to those obtained with HIV-1 vectors pseudotyped with the VSV-G GP. Our results also indicate that RD114 pseudotypes were less toxic than VSV-G pseudotypes in human MSC progenitor assays. Taken together, these results suggest that lentivirus pseudotypes bearing alternative Env GPs provide efficient tools for ex vivo modification of human MSCs.


2014 ◽  
Vol 30 (S1) ◽  
pp. A248-A248
Author(s):  
Kristy Offerman ◽  
Olivia Carulei ◽  
Armin Deffur ◽  
Nicola Douglass ◽  
Anna-Lise Williamson

2019 ◽  
Vol 93 (8) ◽  
Author(s):  
Wenzhong Wei ◽  
Joshua Wiggins ◽  
Duoyi Hu ◽  
Vladimir Vrbanac ◽  
Dane Bowder ◽  
...  

ABSTRACT Lactobacillus bacteria are potential delivery vehicles for biopharmaceutical molecules because they are well-recognized as safe microorganisms that naturally inhabit the human body. The goal of this study was to employ these lactobacilli to combat human immunodeficiency virus type 1 (HIV-1) infection and transmission. By using a chromosomal integration method, we engineered Lactobacillus acidophilus ATCC 4356 to display human CD4, the HIV-1 receptor, on the cell surface. Since human CD4 can bind to any infectious HIV-1 particles, the engineered lactobacilli can potentially capture HIV-1 of different subtypes and prevent infection. Our data demonstrate that the CD4-carrying bacteria are able to adsorb HIV-1 particles and reduce infection significantly in vitro and also block intrarectal HIV-1 infection in a humanized mouse model in preliminary tests in vivo. Our results support the potential of this approach to decrease the efficiency of HIV-1 sexual transmission. IMPORTANCE In the absence of an effective vaccine, alternative approaches to block HIV-1 infection and transmission with commensal bacteria expressing antiviral proteins are being considered. This report provides a proof-of-concept by using Lactobacillus bacteria stably expressing the HIV-1 receptor CD4 to capture and neutralize HIV-1 in vitro and in a humanized mouse model. The stable expression of antiviral proteins, such as CD4, following genomic integration of the corresponding genes into this Lactobacillus strain may contribute to the prevention of HIV-1 sexual transmission.


mBio ◽  
2020 ◽  
Vol 11 (4) ◽  
Author(s):  
Uddhav Timilsina ◽  
Supawadee Umthong ◽  
Brian Lynch ◽  
Aimee Stablewski ◽  
Spyridon Stavrou

ABSTRACT The serine incorporator (SERINC) proteins are multipass transmembrane proteins that affect sphingolipid and phosphatidylserine synthesis. Human SERINC5 and SERINC3 were recently shown to possess antiretroviral activity for a number of retroviruses, including human immunodeficiency virus (HIV), murine leukemia virus (MLV), and equine infectious anemia virus (EIAV). In the case of MLV, the glycosylated Gag (glyco-Gag) protein was shown to counteract SERINC5-mediated restriction in in vitro experiments and the viral envelope was found to determine virion sensitivity or resistance to SERINC5. However, nothing is known about the in vivo function of SERINC5. Antiretroviral function of a host factor in vitro is not always associated with antiretroviral function in vivo. Using SERINC5−/− mice that we had generated, we showed that mouse SERINC5 (mSERINC5) restriction of MLV infection in vivo is influenced not only by glyco-Gag but also by the retroviral envelope. Finally, we also examined the in vivo function of the other SERINC gene with known antiretroviral functions, SERINC3. By using SERINC3−/− mice, we found that the murine homologue, mSERINC3, had no antiretroviral role either in vivo or in vitro. To our knowledge, this report provides the first data showing that SERINC5 restricts retrovirus infection in vivo and that restriction of retrovirus infectivity in vivo is dependent on the presence of both glyco-Gag and the viral envelope. IMPORTANCE This study examined for the first time the in vivo function of the serine incorporator (SERINC) proteins during retrovirus infection. SERINC3 and SERINC5 (SERINC3/5) restrict a number of retroviruses, including human immunodeficiency virus 1 (HIV-1) and murine leukemia virus (MLV), by blocking their entry into cells. Nevertheless, HIV-1 and MLV encode factors, Nef and glycosylated Gag, respectively, that counteract SERINC3/5 in vitro. We recently developed SERINC3 and SERINC5 knockout mice to examine the in vivo function of these genes. We found that SERINC5 restriction is dependent on the absence of glycosylated Gag and the expression of a specific viral envelope glycoprotein. On the other hand, SERINC3 had no antiviral function. Our findings have implications for the development of therapeutics that target SERINC5 during retrovirus infection.


2004 ◽  
Vol 48 (5) ◽  
pp. 1837-1847 ◽  
Author(s):  
Bradley J. Catalone ◽  
Tina M. Kish-Catalone ◽  
Lynn R. Budgeon ◽  
Elizabeth B. Neely ◽  
Maelee Ferguson ◽  
...  

ABSTRACT Clinical trials evaluating the efficacy of nonoxynol-9 (N-9) as a topical microbicide concluded that N-9 offers no in vivo protection against human immunodeficiency virus type 1 (HIV-1) infection, despite demonstrated in vitro inactivation of HIV-1 by N-9. These trials emphasize the need for better model systems to determine candidate microbicide effectiveness and safety in a preclinical setting. To that end, time-dependent in vitro cytotoxicity, as well as in vivo toxicity and inflammation, associated with N-9 exposure were characterized with the goal of validating a mouse model of microbicide toxicity. In vitro studies using submerged cell cultures indicated that human cervical epithelial cells were inherently more sensitive to N-9-mediated damage than human vaginal epithelial cells. These results correlated with in vivo findings obtained by using Swiss Webster mice in which intravaginal inoculation of 1% N-9 or Conceptrol gel (containing 4% N-9) resulted in selective and acute disruption of the cervical columnar epithelial cells 2 h postapplication accompanied by intense inflammatory infiltrates within the lamina propria. Although damage to the cervical epithelium was apparent out to 8 h postapplication, these tissues resembled control tissue by 24 h postapplication. In contrast, minimal damage and infiltration were associated with both short- and long-term exposure of the vaginal mucosa to either N-9 or Conceptrol. These analyses were extended to examine the relative toxicity of polyethylene hexamethylene biguanide (PEHMB), a polybiguanide compound under evaluation as a candidate topical microbicide. In similar studies, in vivo exposure to 1% PEHMB caused minimal damage and inflammation of the genital mucosa, a finding consistent with the demonstration that PEHMB was >350-fold less cytotoxic than N-9 in vitro. Collectively, these studies highlight the murine model of toxicity as a valuable tool for the preclinical assessment of toxicity and inflammation associated with exposure to candidate topical microbicides.


2022 ◽  
Author(s):  
Claudia Tonelli ◽  
Astrid Deschênes ◽  
Melissa A. Yao ◽  
Youngkyu Park ◽  
David A. Tuveson

Pancreatic ductal adenocarcinoma (PDA) is a deadly disease with few treatment options. There is an urgent need to better understand the molecular mechanisms that drive disease progression, with the ultimate aim of identifying early detection markers and clinically actionable targets. To investigate the transcriptional and morphological changes associated with pancreatic cancer progression, we analyzed the KrasLSLG12D/+; Trp53LSLR172H/+; Pdx1-Cre (KPC) mouse model. We have identified an intermediate cellular event during pancreatic carcinogenesis in the KPC mouse model of PDA that is represented by a subpopulation of tumor cells that express KrasG12D, p53R172H and one allele of wild-type Trp53. In vivo, these cells represent a histological spectrum of pancreatic intraepithelial neoplasia (PanIN) and acinar-to-ductal metaplasia (ADM) and rarely proliferate. Following loss of wild-type p53, these precursor lesions undergo malignant de-differentiation and acquire invasive features. We have established matched organoid cultures of pre-invasive and invasive cells from murine PDA. Expression profiling of the organoids led to the identification of markers of the pre-invasive cancer cells in vivo and mechanisms of disease aggressiveness.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2352-2352
Author(s):  
Joseph S. Anderson ◽  
Jon Walker ◽  
Louisa Wirthlin ◽  
John Javien ◽  
Jan A. Nolta ◽  
...  

Abstract In vivo mouse models for safety and efficacy studies of anti-HIV gene therapeutics have been lacking in their ability to evaluate normal systemic hematopoiesis with the development of a functional immune system. These deficiencies in modeling these normal and essential physiologies can now be generated in the recently developed NOD/SCIDγc−/− mouse model. Human CD34+ progenitor cells after intrahepatic injection will undergo multi-organ engraftment generating a functional thymus along with the production of T cells, B cells, and macrophages. Upon injection with various strains of HIV-1, engrafted mice display a disseminated infection due to viral replication in human T cells and macrophages. Infected mice acquire characteristics of increased viremia over time with human CD4+ T cell depletion. Anti-HIV immune responses can also be generated in mice with high viremia. Here we demonstrate the successful engraftment of NOD/SCIDγc−/− mice after injection with human CD34+ progenitor cells isolated from umbilical cord blood. Human cell engraftment was observed in both primary and secondary lymphoid organs including the bone marrow (B cells and macrophages), thymus (T cells), spleen (T cells and B cells), lymph nodes (T cells and B cells), and peripheral blood (T cells and B cells). Human CD34+ cells were found in the liver concluding either organ retention from the initial injection or circulation in the peripheral blood. After displaying a high level of engraftment (>50%), we are now able to proceed with evaluating a number of anti- HIV gene therapeutic constructs for pre-clinical testing. These lentiviral vector constructs include a CCR5 shRNA which has been previously shown to knock down complete expression of CCR5, a human/rhesus macaque chimeric isoform of TRIM5α capable of potently inhibiting HIV-1 infection at the pre-integration step, and combination constructs containing multiple anti-HIV genes. The NOD/SCIDγc−/− mouse model will allow us to evaluate both the safety of these various anti-HIV lentiviral constructs in generating normal functioning transgenic immune system cells and also the efficacy of these anti- HIV genes in inhibiting HIV-1 infection in vivo. With the ability to facilitate multilineage human cell engraftment with the susceptibility for HIV infection, this in vivo model allows for the evaluation of anti-HIV gene therapeutic constructs in a stem cell-based setting. Lentiviral vector transgenic cells can now be tested for their capacity for normal immune system reconstitution.


2012 ◽  
Vol 93 (4) ◽  
pp. 900-905 ◽  
Author(s):  
Willie M. Greggs ◽  
Christine L. Clouser ◽  
Steven E. Patterson ◽  
Louis M. Mansky

Feline leukemia virus (FeLV) is a gammaretrovirus that is a significant cause of neoplastic-related disorders affecting cats worldwide. Treatment options for FeLV are limited, associated with serious side effects, and can be cost-prohibitive. The development of drugs used to treat a related retrovirus, human immunodeficiency virus type 1 (HIV-1), has been rapid, leading to the approval of five drug classes. Although structural differences affect the susceptibility of gammaretroviruses to anti-HIV drugs, the similarities in mechanism of replication suggest that some anti-HIV-1 drugs may also inhibit FeLV. This study demonstrates the anti-FeLV activity of four drugs approved by the US FDA (Food and Drug Administration) at non-toxic concentrations. Of these, tenofovir and raltegravir are anti-HIV-1 drugs, while decitabine and gemcitabine are approved to treat myelodysplastic syndromes and pancreatic cancer, respectively, but also have anti-HIV-1 activity in cell culture. Our results indicate that these drugs may be useful for FeLV treatment and should be investigated for mechanism of action and suitability for veterinary use.


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