scholarly journals Long-Lasting Enfuvirtide Carrier Pentasaccharide Conjugates with Potent Anti-Human Immunodeficiency Virus Type 1 Activity

2009 ◽  
Vol 54 (1) ◽  
pp. 134-142 ◽  
Author(s):  
Thierry Huet ◽  
Olivier Kerbarh ◽  
Dominique Schols ◽  
Pascal Clayette ◽  
Cécile Gauchet ◽  
...  

ABSTRACT Enfuvirtide (also known as Fuzeon, T-20, or DP-178) is an antiretroviral fusion inhibitor which prevents human immunodeficiency virus type 1 (HIV-1) from entering host cells. This linear 36-mer synthetic peptide is indicated, in combination with other antiretroviral agents, for the treatment of HIV-1-infected individuals and AIDS patients with multidrug-resistant HIV infections. Although enfuvirtide is an efficient anti-HIV-1 drug, its clinical use is limited by a short plasma half-life, i.e., approximately 2 h, which requires twice-daily subcutaneous injections, often resulting in skin sensitivity reaction side effects at the injection sites. Ultimately, 80% of patients stop enfuvirtide treatment within 6 months because of these side effects. We report on the development of long-lasting enfuvirtide conjugates by the use of the site-specific conjugation of enfuvirtide to an antithrombin-binding carrier pentasaccharide (CP) through polyethylene glycol (PEG) linkers of various lengths. These conjugates showed consistent and broad anti-HIV-1 activity in the nanomolar range. The coupling of the CP to enfuvirtide only moderately affected the in vitro anti-HIV-1 activity in the presence of antithrombin. Most importantly, one of these conjugates, enfuvirtide-PEG12-CP (EP40111), exhibited a prolonged elimination half-life of more than 10 h in rat plasma compared to the half-life of native enfuvirtide, which was 2.8 h. On the basis of the pharmacokinetic properties of antithrombin-binding pentasaccharides, the anticipated half-life of EP40111 in humans would putatively be about 120 h, which would allow subcutaneous injection once a week instead of twice daily. In conclusion, EP40111 is a promising compound with strong potency as a novel long-lasting anti-HIV-1 drug.

2005 ◽  
Vol 49 (8) ◽  
pp. 3474-3482 ◽  
Author(s):  
Katsunori Takashima ◽  
Hiroshi Miyake ◽  
Naoyuki Kanzaki ◽  
Yoshihiko Tagawa ◽  
Xin Wang ◽  
...  

ABSTRACT TAK-220 is a member of a novel class of chemokine receptor antagonists and is highly specific to CCR5, as determined by receptor binding and calcium mobilization assays. The compound selectively inhibited coreceptor-mediated entry of human immunodeficiency virus type 1 (HIV-1) into host cells and HIV-1 infection mediated by CCR5. TAK-220 inhibited the replication of six CCR5-using (R5) HIV-1 clinical isolates in peripheral blood mononuclear cells (PBMCs) with a mean 90% effective concentration of 13 nM. The anti-HIV-1 activity of TAK-220 was not affected by addition of high concentrations of human serum. It equally inhibited R5 HIV-1 replication in PBMCs obtained from eight different donors, irrespective of the levels of viral production. Furthermore, the anti-HIV-1 activity of TAK-220 was found to be subtype independent. TAK-220 did not induce CCR5 internalization but blocked the binding of two monoclonal antibodies that recognize the second extracellular loop of CCR5 in CCR5-expressing cells. These results suggest that TAK-220 selectively inhibits R5 HIV-1 replication by interfering with coreceptor-mediated entry of the virus into host cells. At a dose of 5 mg/kg of body weight, TAK-220 showed oral bioavailabilities of 9.5 and 28.9% in rats and monkeys, respectively. Thus, TAK-220 is a promising candidate for the treatment of HIV-1 infection.


1998 ◽  
Vol 9 (5) ◽  
pp. 412-421 ◽  
Author(s):  
C Chamorro ◽  
M-J Camarasa ◽  
M-J Pérez-Pérez ◽  
E de Clercq ◽  
J Balzarini ◽  
...  

Novel derivatives of the potent human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) inhibitor TSAO-T have been designed, synthesized and tested for their in vitro antiretro-viral activity against HIV. These TSAO-T derivatives have been designed as potential bidentate inhibitors of HIV-1 RT, which combine in their structure the functionality of a non-nucleoside RT inhibitor (TSAO-T) and a bivalent ion-chelating moiety (a β-diketone moiety) linked through an appropriate spacer to the N-3 of thymine of TSAO-T . Some of the new compounds have an anti-HIV-1 activity comparable to that of the parent compound TSAO-T, but display a markedly increased antiviral selectivity. There was a clear relationship between antiviral activity and the length of the spacer group that links the TSAO molecule with the chelating moiety. A shorter spacer invariably resulted in increased antiviral potency. None of the TSAO-T derivatives were endowed with anti-HIV-2 activity.


2008 ◽  
Vol 82 (14) ◽  
pp. 7022-7033 ◽  
Author(s):  
Terrence M. Dobrowsky ◽  
Yan Zhou ◽  
Sean X. Sun ◽  
Robert F. Siliciano ◽  
Denis Wirtz

ABSTRACT The fusion of human immunodeficiency virus type 1 (HIV-1) to host cells is a dynamic process governed by the interaction between glycoproteins on the viral envelope and the major receptor, CD4, and coreceptor on the surface of the cell. How these receptors organize at the virion-cell interface to promote a fusion-competent site is not well understood. Using single-molecule force spectroscopy, we map the tensile strengths, lifetimes, and energy barriers of individual intermolecular bonds between CCR5-tropic HIV-1 gp120 and its receptors CD4 and CCR5 or CXCR4 as a function of the interaction time with the cell. According to the Bell model, at short times of contact between cell and virion, the gp120-CD4 bond is able to withstand forces up to 35 pN and has an initial lifetime of 0.27 s and an intermolecular length of interaction of 0.34 nm. The initial bond also has an energy barrier of 6.7 kB T (where kB is Boltzmann's constant and T is absolute temperature). However, within 0.3 s, individual gp120-CD4 bonds undergo rapid destabilization accompanied by a shortened lifetime and a lowered tensile strength. This destabilization is significantly enhanced by the coreceptor CCR5, not by CXCR4 or fusion inhibitors, which suggests that it is directly related to a conformational change in the gp120-CD4 bond. These measurements highlight the instability and low tensile strength of gp120-receptor bonds, uncover a synergistic role for CCR5 in the progression of the gp120-CD4 bond, and suggest that the cell-virus adhesion complex is functionally arranged about a long-lived gp120-coreceptor bond.


2002 ◽  
Vol 76 (22) ◽  
pp. 11584-11595 ◽  
Author(s):  
Mathias Viard ◽  
Isabella Parolini ◽  
Massimo Sargiacomo ◽  
Katia Fecchi ◽  
Carlo Ramoni ◽  
...  

ABSTRACT In this study we examined the effects of target membrane cholesterol depletion and cytoskeletal changes on human immunodeficiency virus type 1 (HIV-1) Env-mediated membrane fusion by dye redistribution assays. We found that treatment of peripheral blood lymphocytes (PBL) with methyl-β-cyclodextrin (MβCD) or cytochalasin reduced their susceptibility to membrane fusion with cells expressing HIV-1 Env that utilize CXCR4 or CCR5. However, treatment of human osteosarcoma (HOS) cells expressing high levels of CD4 and coreceptors with these agents did not affect their susceptibility to HIV-1 Env-mediated membrane fusion. Removal of cholesterol inhibited stromal cell-derived factor-1α- and macrophage inflammatory protein 1β-induced chemotaxis of both PBL and HOS cells expressing CD4 and coreceptors. The fusion activity as well as the chemotactic activity of PBL was recovered by adding back cholesterol to these cells. Confocal laser scanning microscopy analysis indicated that treatment of lymphocytes with MβCD reduced the colocalization of CD4 or of CXCR4 with actin presumably in microvilli. These findings indicate that, although cholesterol is not required for HIV-1 Env-mediated membrane fusion per se, its depletion from cells with relatively low coreceptor densities reduces the capacity of HIV-1 Env to engage coreceptor clusters required to trigger fusion. Furthermore, our results suggest that coreceptor clustering may occur in microvilli that are supported by actin polymerization.


2007 ◽  
Vol 51 (9) ◽  
pp. 3264-3272 ◽  
Author(s):  
Jörn Lötsch ◽  
Sebastian Harder ◽  
Martin Stürmer ◽  
Hans-Wilhelm Doerr ◽  
Gerd Geisslinger ◽  
...  

ABSTRACT The objective of this study was to identify parameters among saquinavir pharmacokinetics, patients' demographics or comedications, to be addressed for improved personalized therapy. The presence of human immunodeficiency virus type 1 (HIV-1) RNA at therapy week 48 (principal target parameter), CD4 cell count at week 48, infections and side effects during 48 weeks, indicators of liver toxicity and lipid abnormalities at week 48, and a 12-h saquinavir plasma concentration-versus-time profile were assessed in 56 patients receiving saquinavir-ritonavir (1,000 and 100 mg, respectively) twice daily (44 therapy-naïve and 12 antiretrovirally pretreated patients) for association with saquinavir plasma concentrations, demographics, baseline values of target parameters, and coadministered antiretrovirals. Antiretroviral failure was observed in 8 of the 56 patients in whom HIV-1 RNA was detectable at week 48. This therapeutic failure was not associated with individual saquinavir pharmacokinetics. More likely, therapeutic failure was related to incidences interfering with antiretroviral therapy, causing therapy interruptions or incompliance. Weak associations were, however, seen between high maximum saquinavir plasma concentrations and both CD4 counts of ≥200 cells μl−1 at week 48 (P = 0.014) and constitutional side effects during 48 weeks (P = 0.002). However, patients with high CD4 counts and constitutional side effects were not identical (P = 0.53). Saquinavir therapeutic drug monitoring in patients infected with protease inhibitor-susceptible HIV-1 taking saquinavir-ritonavir (1,000 and 100 mg, respectively) is not demanded for improving the antiretroviral effect. It may be contemplated in cases with constitutional side effects or low CD4 counts with weak immune responses.


2016 ◽  
Vol 71 (5-6) ◽  
pp. 105-109 ◽  
Author(s):  
Zhiping Che ◽  
Yuee Tian ◽  
Zhenjie Hu ◽  
Yingwu Chen ◽  
Shengming Liu ◽  
...  

Abstract Fifteen N-arylsulfonyl-3-propionylindoles (3a–o) were prepared and preliminarily evaluated as in vitro inhibitors of human immunodeficiency virus type-1 (HIV-1). Three compounds 3c, 3g and 3i exhibited potent anti-HIV-1 activity with effective concentration (EC50) values of 0.8, 4.0 and 1.2 μg/mL, and therapeutic index (TI) values of 11.7, 16.6 and 84.1, respectively. N-(m-Nitro)phenylsulfonyl-3-propionyl-6-methylindole (3i) exhibited the most promising and best activity against HIV-1 replication. The cytotoxicity of these compounds was assessed as well.


2008 ◽  
Vol 82 (13) ◽  
pp. 6349-6358 ◽  
Author(s):  
Yuxian He ◽  
Jianwei Cheng ◽  
Jingjing Li ◽  
Zhi Qi ◽  
Hong Lu ◽  
...  

ABSTRACT Human immunodeficiency virus type 1 (HIV-1) entry into the host cell involves a cascade of events and currently represents one of most attractive targets in the search for new antiviral drugs. The fusion-active gp41 core structure is a stable six-helix bundle (6-HB) folded by its trimeric N-terminal heptad repeat (NHR) and C-terminal heptad repeat (CHR). Peptides derived from the CHR region of HIV-1 gp41 are potent fusion inhibitors that target the NHR to block viral and cellular membrane fusion in a dominant negative fashion. However, all CHR peptides reported to date are derived primarily from residues 628 to 673 of gp41; little attention has been paid to the upstream sequence of the pocket binding domain (PBD) in the CHR. Here, we have identified a motif (621QIWNNMT627) located at the upstream region of the gp41 CHR, immediately adjacent to the PBD (628WMEWEREI635). Biophysical characterization demonstrated that this motif is critical for the stabilization of the gp41 6-HB core. The peptide CP621-652, containing the 621QIWNNMT627 motif, was able to interact with T21, a counterpart peptide derived from the NHR, to form a typical 6-HB structure with a high thermostability (thermal unfolding transition [T m ] value of 82°C). In contrast, the 6-HB formed by the peptides N36 and C34, which has been considered to be a core structure of the fusion-active gp41, had a T m of 64°C. Different from T-20 (brand name Fuseon), which is the first and only HIV-1 fusion inhibitor approved for clinical use, CP621-652 could efficiently block 6-HB formation in a dose-dependent manner. Significantly, CP621-652 had potent inhibitory activity against HIV-1-mediated cell-cell fusion and infection, especially against T-20- and C34-resistant virus. Therefore, our works provide important information for understanding the core structure of the fusion-active gp41 and for designing novel anti-HIV peptides.


1999 ◽  
Vol 73 (2) ◽  
pp. 887-896 ◽  
Author(s):  
Ulrich Schubert ◽  
Stephan Bour ◽  
Ronald L. Willey ◽  
Klaus Strebel

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) Vpu and Env proteins are expressed from a bicistronic mRNA. To address the biological significance of the coordinated expression ofvpu and env, we compared the relative effects on particle release of HIV-1 isolates containing an intactvpu gene or carrying point mutations in its initiation codon or internal deletions, respectively. We found that the primary AD8 isolate, which is unable to express vpu due to a mutation in its translation initiation codon, was able to replicate in primary macrophages and peripheral blood mononuclear cells with efficiency similar to that of an isogenic variant expressing Vpu. Interestingly, AD8 lacking a vpu initiation codon produced higher levels of Env protein than its Vpu-expressing isogenic variant. In contrast, disabling Vpu without removing the vpuinitiation codon did not alter Env expression but significantly reduced virus production. AD8 Env when provided in trans was capable of enhancing release not only of AD8 particles but also of viruses of the T-cell-tropic NL4-3 isolate. We conclude that AD8 Env encodes a Vpu-like activity similar to that previously reported for HIV-2 Env proteins and is thus able to augment virus secretion. When expressed at elevated levels, i.e., following mutation of thevpu initiation codon, AD8 Env was able to compensate for the lack of Vpu and thereby ensure efficient virus release. Thus, the ability to regulate virus release is redundant in AD8 and can be controlled by either Vpu or Env. Since Vpu controls several independent functions, including CD4 degradation, our results suggest that some HIV-1 isolates may have evolved a mechanism to regulate Vpu activity without compromising their ability to efficiently replicate in the host cells.


2006 ◽  
Vol 80 (15) ◽  
pp. 7645-7657 ◽  
Author(s):  
Keyang Chen ◽  
Jialing Huang ◽  
Chune Zhang ◽  
Sophia Huang ◽  
Giuseppe Nunnari ◽  
...  

ABSTRACT The interferon (IFN) system, including various IFNs and IFN-inducible gene products, is well known for its potent innate immunity against wide-range viruses. Recently, a family of cytidine deaminases, functioning as another innate immunity against retroviral infection, has been identified. However, its regulation remains largely unknown. In this report, we demonstrate that through a regular IFN-α/β signal transduction pathway, IFN-α can significantly enhance the expression of apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like 3G (APOBEC3G) in human primary resting but not activated CD4 T cells and the amounts of APOBEC3G associated with a low molecular mass. Interestingly, short-time treatments of newly infected resting CD4 T cells with IFN-α will significantly inactivate human immunodeficiency virus type 1 (HIV-1) at its early stage. This inhibition can be counteracted by APOBEC3G-specific short interfering RNA, indicating that IFN-α-induced APOBEC3G plays a key role in mediating this anti-HIV-1 process. Our data suggest that APOBEC3G is also a member of the IFN system, at least in resting CD4 T cells. Given that the IFN-α/APOBEC3G pathway has potent anti-HIV-1 capability in resting CD4 T cells, augmentation of this innate immunity barrier could prevent residual HIV-1 replication in its native reservoir in the post-highly active antiretroviral therapy era.


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