Fusion Inhibitor

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Shibo Jiang - One of the best experts on this subject based on the ideXlab platform.

  • A Peptide-Based HIV-1 Fusion Inhibitor with Two Tail-Anchors and Palmitic Acid Exhibits Substantially Improved In Vitro and Ex Vivo Anti-HIV-1 Activity and Prolonged In Vivo Half-Life
    MDPI AG, 2019
    Co-Authors: Giselle Rasquinha, Qian Wang, Shibo Jiang
    Abstract:

    Enfuvirtide (T20) is the first U.S. FDA-approved HIV Fusion Inhibitor-based anti-HIV drug. Its clinical application is limited because of its low potency and short half-life. We previously reported that peptide HP23-E6-IDL, containing both N- and C-terminal anchor-tails, exhibited stronger potency and a better resistance profile than T20. Here we designed an analogous peptide, YIK, by introducing a mutation, T639I, and then a lipopeptide, YIK-C16, by adding palmitic acid (C16) at the C-terminus of YIK. We found that YIK-C16 was 4.4- and 3.6-fold more potent than HP23-E6-IDL and YIK against HIV-1IIIB infection and 13.3- and 10.5-fold more effective than HP23-E6-IDL and YIK against HIV-1Bal infection, respectively. Consistently, the ex vivo anti-HIV-1IIIB activity, as determined by the highest dilution-fold of the serum causing 50% inhibition of HIV-1 infection, of YIK-C16 in the sera of pretreated mice was remarkably higher than that of YIK or HP23-E6-IDL. The serum half-life (t1/2 = 5.9 h) of YIK-C16 was also significantly longer than that of YIK (t1/2 = 1.3 h) and HP23-E6-IDL (t1/2 = 1.0 h). These results suggest that the lipopeptide YIK-C16 shows promise for further development as a new anti-HIV drug with improved anti-HIV-1 activity and a prolonged half-life

  • intranasally administered peptidic viral Fusion Inhibitor protected hdpp4 transgenic mice from mers cov infection
    The Lancet, 2015
    Co-Authors: Shuai Xia, Shibo Jiang, Xinrong Tao, Tania Garron, Chiente K Tseng
    Abstract:

    Abstract Background Middle East respiratory syndrome coronavirus (MERS-CoV), a new coronavirus that emerged in 2012, causes severe and fatal acute respiratory illness in man. Its high mortality (roughly 38%) has raised public fear worldwide, calling for the development of effective and safe therapeutics to combat MERS-CoV infection. On the basis of our previous work in development of peptide Fusion Inhibitors against HIV and SARS-CoV, and the crystal structure of the six-helix-bundle core of the MERS-CoV spike protein, we identified a peptide derived from the MERS-CoV S protein S2 subunit HR2 domain (HR2P) with a potent Inhibitory activity against S-protein-mediated cell–cell Fusion. Here, we tested an HR2P analogue with improved pharmaceutical properties, HR2P-M2, for its Inhibitory activity against MERS-CoV infection in vitro and in vivo (appendix). Methods We assessed the anti-MERS-CoV activities of HR2P-M2 in vitro with pseudotyped MERS-CoVs in cell culture and in vivo with live MERS-CoVs in hDPP4-transgenic mice. The activities of HR2P-M2 to form six-helix bundles with HR1 peptides and to block Fusion core formation between HR1 and HR2 peptides were studied using methods such as circular dichroism, N-PAGE, and FN-PAGE. Findings HR2P-M2 was highly effective in blockade of cell–cell Fusion mediated by MERS-CoV S proteins and inhibition of infection by MERS pseudoviruses expressing MERS-CoV S protein with or without mutation in the HR1 region, with IC50 (the concentration causing 50% inhibition) less than 0·7 μM. HR2P-M2 bound to the HR1 peptide to form stable six-helix bundles and blocked Fusion core formation between the HR1 and HR2 peptides. Intranasal administration of HR2P-M2 before viral challenge fully protected hDPP4-transgenic mice (n=5) from MERS-CoV infection, whereas all the untreated mice (n=5) died 8 days after viral challenge. Interpretation Our findings suggest that the HR2P-M2 peptide merits further development as an effective and safe anti-MERS-CoV drug, alone or in combination with other antiviral drugs, to treat MERS-CoV-infected patients and to prevent the disease in high-risk populations, including health-care workers and family members of patients. Funding This work was supported by grants from the National Science Fund of China (81173098 and 81361120378 to SJ, 81373456 to LL), the National 973 Program of China (2012CB519001 to SJ), and the US National Biocontainment Laboratories Operations Support (5UC7AI094660-05 to C-TKT). The funders had no role in interpretation of the findings and writing of this abstract.

  • nonneutralizing antibodies induced by the hiv 1 gp41 nhr domain gain neutralizing activity in the presence of the hiv Fusion Inhibitor enfuvirtide a potential therapeutic vaccine strategy
    Journal of Virology, 2015
    Co-Authors: Qian Wang, Shibo Jiang, Xiaojie Zhu
    Abstract:

    A key barrier against developing preventive and therapeutic human immunodeficiency virus (HIV) vaccines is the inability of viral envelope glycoproteins to elicit broad and potent neutralizing antibodies. However, in the presence of Fusion Inhibitor enfuvirtide, we show that the nonneutralizing antibodies induced by the HIV type 1 (HIV-1) gp41 N-terminal heptad repeat (NHR) domain (N63) exhibit potent and broad neutralizing activity against laboratory-adapted HIV-1 strains, including the drug-resistant variants, and primary HIV-1 isolates with different subtypes, suggesting the potential of developing gp41-targeted HIV therapeutic vaccines.

  • structure based discovery of middle east respiratory syndrome coronavirus Fusion Inhibitor
    Nature Communications, 2014
    Co-Authors: Qi Liu, Qian Wang, Yun Zhu, Lili Qin, Jasper F W Chan, Kwokhung Chan, Kwokyung Yuen, Rongguang Zhang, Shibo Jiang
    Abstract:

    A novel human coronavirus, Middle East respiratory syndrome coronavirus (MERS-CoV), has caused outbreaks of a SARS-like illness with high case fatality rate. The reports of its person-to-person transmission through close contacts have raised a global concern about its pandemic potential. Here we characterize the six-helix bundle Fusion core structure of MERS-CoV spike protein S2 subunit by X-ray crystallography and biophysical analysis. We find that two peptides, HR1P and HR2P, spanning residues 998-1039 in HR1 and 1251-1286 in HR2 domains, respectively, can form a stable six-helix bundle Fusion core structure, suggesting that MERS-CoV enters into the host cell mainly through membrane Fusion mechanism. HR2P can effectively inhibit MERS-CoV replication and its spike protein-mediated cell-cell Fusion. Introduction of hydrophilic residues into HR2P results in significant improvement of its stability, solubility and antiviral activity. Therefore, the HR2P analogues have good potential to be further developed into effective viral Fusion Inhibitors for treating MERS-CoV infection.

  • A novel chimeric protein-based HIV-1 Fusion Inhibitor targeting gp41 glycoprotein with high potency and stability.
    Journal of Biological Chemistry, 2011
    Co-Authors: Chungen Pan, Lifeng Cai, Shibo Jiang
    Abstract:

    T20 (enfuvirtide, Fuzeon) is the first generation HIV-1 Fusion Inhibitor approved for salvage therapy of HIV-1-infected patients refractory to current antiretroviral drugs. However, its application is limited by the high cost of peptide synthesis, rapid proteolysis, and poor efficacy against emerging drug-resistant strains. Here we reported the design of a novel chimera protein-based Fusion Inhibitor targeting gp41, TLT35, that uses a flexible 35-mer linker to couple T20 and T1144, the first and next generation HIV-1 Fusion Inhibitors, respectively. TLT35, which was expressed in Escherichia coli with good yield, showed low nm activity against HIV-1-mediated cell-cell Fusion and infection by laboratory-adapted HIV-1 strains (X4 or R5), including T20-resistant variants and primary HIV-1 isolates of clades A to G and group O (R5 or X4R5). TLT35 was stable in human sera and in peripheral blood mononuclear cell culture and was more resistant to proteolysis than either T20 or T1144 alone. Circular dichroism spectra showed that TLT35 folded into a thermally stable conformation with high α-helical content and T(m) value in aqueous solution. It formed a highly stable complex with gp41 N-terminal heptad repeat peptide and blocked formation of the gp41 six-helix-bundle core. These merits combined with an anticipated low production cost for expression of TLT35 in E. coli make this novel protein-based Fusion Inhibitor a promising candidate for further development as an anti-HIV-1 microbicide or therapeutic for the prevention and treatment of HIV-1 infection.

Huihui Chong - One of the best experts on this subject based on the ideXlab platform.

  • structural and functional characterization of hiv 1 cell Fusion Inhibitor t20
    AIDS, 2019
    Co-Authors: Huihui Chong, Xiaohui Ding, Yuanmei Zhu, Sheng Cui, Xiujuan Zhang, Xinquan Wang
    Abstract:

    Objective The peptide drug T20 (enfuvirtide), derived from the C-terminal heptad repeat region of HIV-1 gp41, is the only membrane Fusion Inhibitor available for treatment of viral infection; however, its mechanism of action remains elusive and its structural basis is lacking. Design We focused on determining the crystal structure of T20 in complex with N39, a target mimic peptide derived from the N-terminal heptad repeat region of gp41. On the basis of the structural information, the mechanisms of action of T20 and its resistance were further characterized. Methods A panel of peptides was synthesized. The T20/N39 complex was assembled for crystallization studies. Circular dichroism spectroscopy, isothermal titration calorimetry (ITC), native polyacrylamide gel electrophoresis (N-PAGE), and mutational analysis were applied to analyze the structural and functional properties. Results A crystal structure of six-helical bundle (6-HB) structure formed by T20 and N39 was determined with a resolution limit of 2.3 A, which revealed the critical intrahelical and interhelical interactions underlying the mechanism of action of T20 and its resistance mutations. Although the structural properties in the C-terminal tryptophan-rich motif (TRM) of T20 and the Fusion peptide proximal region (FPPR) of N39 could not be finely defined by the structure, the data from biophysical and mutational analyses verified the essential roles of the TRM and FPPR motifs for the binding and Inhibitory activities of T20. Conclusion For the first time, our studies provide a structural basis of T20, which help our understanding on the mechanisms of HIV-1 Fusion and its inhibition.

  • Monotherapy with a low-dose lipopeptide HIV Fusion Inhibitor maintains long-term viral suppression in rhesus macaques
    2019
    Co-Authors: Huihui Chong, Jing Xue, Zhe Cong, Yuanmei Zhu, Ting Chen, Qiang Wei, Chuan Qin
    Abstract:

    Combination antiretroviral therapy (cART) dramatically improves survival of HIV-infected patients, but lifelong treatment can ultimately result in cumulative toxicities and drug resistance, thus necessitating the development of new drugs with significantly improved pharmaceutical profiles. We recently found that the Fusion Inhibitor T-20 (enfuvirtide)-based lipopeptides possess dramatically increased anti-HIV activity. Herein, a group of novel lipopeptides were designed with different lengths of fatty acids, identifying a stearic acid-modified lipopeptide (LP-80) with the most potent anti-HIV activity. It inhibited a large panel of divergent HIV subtypes with a mean IC50 in the extremely low picomolar range, being > 5,300-fold more active than T-20 and the neutralizing antibody VRC01. It also sustained the potent activity against T-20-resistant mutants and exhibited very high therapeutic selectivity index. Pharmacokinetics of LP-80 in rats and monkeys verified its potent and long-acting anti-HIV activity. In the monkey, subcutaneous administration of 3 mg/kg LP-80 yielded serum concentrations of 1,147 ng/ml after injection 72 h and 9 ng/ml after injection 168 h (7 days), equivalent to 42,062- and 330-fold higher than the measured IC50 value. In SHIV infected rhesus macaques, a single low-dose LP-80 (3 mg/kg) sharply reduced viral loads to below the limitation of detection, and twice-weekly monotherapy could maintain long-term viral suppression.

  • molecular mechanism of hiv 1 resistance to sifuvirtide a clinical trial approved membrane Fusion Inhibitor
    Journal of Biological Chemistry, 2018
    Co-Authors: Xiaohui Ding, Huihui Chong, Yuanmei Zhu, Zixuan Liu, Huanmian Wei, Sheng Cui
    Abstract:

    Host cell infection with HIV-1 requires Fusion of viral and cell membranes. Sifuvirtide (SFT) is a peptide-based HIV-1 Fusion Inhibitor approved for phase III clinical trials in China. Here, we focused on characterizing HIV-1 variants highly resistant to SFT to gain insight into the molecular resistance mechanism. Three primary substitutions (V38A, A47I, and Q52R) located at the Inhibitor-binding site of HIV-1's envelope protein (Env) and one secondary substitution (N126K) located at the C-terminal heptad repeat region of the viral protein gp41, which is part of the envelope, conferred high SFT resistance and cross-resistance to the anti-HIV-1 drug T20 and the template peptide C34. Interestingly, SFT's resistance profile could be dramatically improved with an M-T hook structure-modified SFT (MTSFT) and with short-peptide Inhibitors that mainly target the gp41 pocket (2P23 and its lipid derivative LP-19). We found that the V38A and Q52R substitutions reduce the binding stabilities of SFT, C34, and MTSFT, but they had no effect on the binding of 2P23 and LP-19; in sharp contrast, the A47I substitution enhanced Fusion Inhibitor binding. Furthermore, the primary resistance substitutions impaired Env-mediated membrane Fusion and cell entry and changed the conformation of the gp41 core structure. Importantly, whereas the V38A and Q52R substitutions disrupted the N-terminal helix of gp41, a single A47I substitution greatly enhanced its thermostability. Taken together, our results provide crucial structural insights into the mechanism of HIV-1 resistance to gp41-dependent Fusion Inhibitors, which may inform the development of additional anti-HIV drugs.

  • exceptional potency and structural basis of a t1249 derived lipopeptide Fusion Inhibitor against hiv 1 hiv 2 and simian immunodeficiency virus
    Journal of Biological Chemistry, 2018
    Co-Authors: Xiujuan Zhang, Huihui Chong, Xiaohui Ding, Xinquan Wang, Jinsheng He, Yuxian He
    Abstract:

    : Enfuvirtide (T20) is the only viral Fusion Inhibitor approved for clinical use, but it has relatively weak anti-HIV activity and easily induces drug resistance. In succession to T20, T1249 has been designed as a 39-mer peptide composed of amino acid sequences derived from HIV-1, HIV-2, and simian immunodeficiency virus (SIV); however, its development has been suspended due to formulation difficulties. We recently developed a T20-based lipopeptide (LP-40) showing greatly improved pharmaceutical properties. Here, we generated a T1249-based lipopeptide, termed LP-46, by replacing its C-terminal tryptophan-rich sequence with fatty acid. As compared with T20, T1249, and LP-40, the truncated LP-46 (31-mer) had dramatically increased activities in inhibiting a large panel of HIV-1 subtypes, with IC50 values approaching low picomolar concentrations. Also, LP-46 was an exceptionally potent Inhibitor against HIV-2, SIV, and T20-resistant variants, and it displayed obvious synergistic effects with LP-40. Furthermore, we showed that LP-46 had increased helical stability and binding affinity with the target site. The crystal structure of LP-46 in complex with a target surrogate revealed its critical binding motifs underlying the mechanism of action. Interestingly, it was found that the introduced pocket-binding domain in LP-46 did not interact with the gp41 pocket as expected; instead, it adopted a mode similar to that of LP-40. Therefore, our studies have provided an exceptionally potent and broad Fusion Inhibitor for developing new anti-HIV drugs, which can also serve as a tool to exploit the mechanisms of viral Fusion and inhibition.

  • enfuvirtide t20 based lipopeptide is a potent hiv 1 cell Fusion Inhibitor implications for viral entry and inhibition
    Journal of Virology, 2017
    Co-Authors: Xiaohui Ding, Huihui Chong, Yuanmei Zhu, Huamian Wei, Xiujuan Zhang, Xinquan Wang
    Abstract:

    The peptide drug enfuvirtide (T20) is the only viral Fusion Inhibitor used in combination therapy for HIV-1 infection, but it has relatively low antiviral activity and easily induces drug resistance. Emerging studies demonstrate that lipopeptide-based Fusion Inhibitors, such as LP-11 and LP-19, which mainly target the gp41 pocket site, have greatly improved antiviral potency and in vivo stability. In this study, we focused on developing a T20-based lipopeptide Inhibitor that lacks pocket-binding sequence and targets a different site. First, the C-terminal tryptophan-rich motif (TRM) of T20 was verified to be essential for its target binding and inhibition; then, a novel lipopeptide, termed LP-40, was created by replacing the TRM with a fatty acid group. LP-40 showed markedly enhanced binding affinity for the target site and dramatically increased Inhibitory activity on HIV-1 membrane Fusion, entry, and infection. Unlike LP-11 and LP-19, which required a flexible linker between the peptide sequence and the lipid moiety, addition of a linker to LP-40 sharply reduced its potency, implying different binding modes with the extended N-terminal helices of gp41. Also, interestingly, LP-40 showed more potent activity than LP-11 in inhibiting HIV-1 Env-mediated cell-cell Fusion while it was less active than LP-11 in inhibiting pseudovirus entry, and the two Inhibitors displayed synergistic antiviral effects. The crystal structure of LP-40 in complex with a target peptide revealed their key binding residues and motifs. Combined, our studies have not only provided a potent HIV-1 Fusion Inhibitor, but also revealed new insights into the mechanisms of viral inhibition.IMPORTANCE T20 is the only membrane Fusion Inhibitor available for treatment of viral infection; however, T20 requires high doses and has a low genetic barrier for resistance, and its Inhibitory mechanism and structural basis remain unclear. Here, we report the design of LP-40, a T20-based lipopeptide Inhibitor that has greatly improved anti-HIV activity and is a more potent Inhibitor of cell-cell Fusion than of cell-free virus infection. The binding modes of two classes of membrane-anchoring lipopeptides (LP-40 and LP-11) verify the current Fusion model in which an extended prehairpin structure bridges the viral and cellular membranes, and their complementary effects suggest a vital strategy for combination therapy of HIV-1 infection. Moreover, our understanding of the mechanism of action of T20 and its derivatives benefits from the crystal structure of LP-40.

Sheng Cui - One of the best experts on this subject based on the ideXlab platform.

  • structural and functional characterization of hiv 1 cell Fusion Inhibitor t20
    AIDS, 2019
    Co-Authors: Huihui Chong, Xiaohui Ding, Yuanmei Zhu, Sheng Cui, Xiujuan Zhang, Xinquan Wang
    Abstract:

    Objective The peptide drug T20 (enfuvirtide), derived from the C-terminal heptad repeat region of HIV-1 gp41, is the only membrane Fusion Inhibitor available for treatment of viral infection; however, its mechanism of action remains elusive and its structural basis is lacking. Design We focused on determining the crystal structure of T20 in complex with N39, a target mimic peptide derived from the N-terminal heptad repeat region of gp41. On the basis of the structural information, the mechanisms of action of T20 and its resistance were further characterized. Methods A panel of peptides was synthesized. The T20/N39 complex was assembled for crystallization studies. Circular dichroism spectroscopy, isothermal titration calorimetry (ITC), native polyacrylamide gel electrophoresis (N-PAGE), and mutational analysis were applied to analyze the structural and functional properties. Results A crystal structure of six-helical bundle (6-HB) structure formed by T20 and N39 was determined with a resolution limit of 2.3 A, which revealed the critical intrahelical and interhelical interactions underlying the mechanism of action of T20 and its resistance mutations. Although the structural properties in the C-terminal tryptophan-rich motif (TRM) of T20 and the Fusion peptide proximal region (FPPR) of N39 could not be finely defined by the structure, the data from biophysical and mutational analyses verified the essential roles of the TRM and FPPR motifs for the binding and Inhibitory activities of T20. Conclusion For the first time, our studies provide a structural basis of T20, which help our understanding on the mechanisms of HIV-1 Fusion and its inhibition.

  • molecular mechanism of hiv 1 resistance to sifuvirtide a clinical trial approved membrane Fusion Inhibitor
    Journal of Biological Chemistry, 2018
    Co-Authors: Xiaohui Ding, Huihui Chong, Yuanmei Zhu, Zixuan Liu, Huanmian Wei, Sheng Cui
    Abstract:

    Host cell infection with HIV-1 requires Fusion of viral and cell membranes. Sifuvirtide (SFT) is a peptide-based HIV-1 Fusion Inhibitor approved for phase III clinical trials in China. Here, we focused on characterizing HIV-1 variants highly resistant to SFT to gain insight into the molecular resistance mechanism. Three primary substitutions (V38A, A47I, and Q52R) located at the Inhibitor-binding site of HIV-1's envelope protein (Env) and one secondary substitution (N126K) located at the C-terminal heptad repeat region of the viral protein gp41, which is part of the envelope, conferred high SFT resistance and cross-resistance to the anti-HIV-1 drug T20 and the template peptide C34. Interestingly, SFT's resistance profile could be dramatically improved with an M-T hook structure-modified SFT (MTSFT) and with short-peptide Inhibitors that mainly target the gp41 pocket (2P23 and its lipid derivative LP-19). We found that the V38A and Q52R substitutions reduce the binding stabilities of SFT, C34, and MTSFT, but they had no effect on the binding of 2P23 and LP-19; in sharp contrast, the A47I substitution enhanced Fusion Inhibitor binding. Furthermore, the primary resistance substitutions impaired Env-mediated membrane Fusion and cell entry and changed the conformation of the gp41 core structure. Importantly, whereas the V38A and Q52R substitutions disrupted the N-terminal helix of gp41, a single A47I substitution greatly enhanced its thermostability. Taken together, our results provide crucial structural insights into the mechanism of HIV-1 resistance to gp41-dependent Fusion Inhibitors, which may inform the development of additional anti-HIV drugs.

  • discovery of critical residues for viral entry and inhibition through structural insight of hiv 1 Fusion Inhibitor cp621 652
    Journal of Biological Chemistry, 2012
    Co-Authors: Huihui Chong, Zonglin Qiu, Xue Yao, Bo Qin, Ruiyun Han, Sandro Waltersperger, Meitian Wang, Sheng Cui
    Abstract:

    The core structure of HIV-1 gp41 is a stable six-helix bundle (6-HB) folded by its trimeric N- and C-terminal heptad repeats (NHR and CHR). We previously identified that the (621)QIWNNMT(627) motif located at the upstream region of gp41 CHR plays critical roles for the stabilization of the 6-HB core and peptide CP621-652 containing this motif is a potent HIV-1 Fusion Inhibitor, however, the molecular determinants underlying the stability and anti-HIV activity remained elusive. In this study, we determined the high-resolution crystal structure of CP621-652 complexed by T21. We find that the (621)QIWNNMT(627) motif does not maintain the α-helical conformation. Instead, residues Met(626) and Thr(627) form a unique hook-like structure (denoted as M-T hook), in which Thr(627) redirects the peptide chain to position Met(626) above the left side of the hydrophobic pocket on the NHR trimer. The side chain of Met(626) caps the hydrophobic pocket, stabilizing the interaction between the pocket and the pocket-binding domain. Our mutagenesis studies demonstrate that mutations of the M-T hook residues could completely abolish HIV-1 Env-mediated cell Fusion and virus entry, and significantly destabilize the interaction of NHR and CHR peptides and reduce the anti-HIV activity of CP621-652. Our results identify an unusual structural feature that stabilizes the six-helix bundle, providing novel insights into the mechanisms of HIV-1 Fusion and inhibition.

  • Structural basis of potent and broad HIV-1 Fusion Inhibitor CP32M
    Journal of Biological Chemistry, 2012
    Co-Authors: Xue Yao, Huihui Chong, Zonglin Qiu, Chao Zhang, Bo Qin, Ruiyun Han, Sandro Waltersperger, Meitian Wang, Sheng Cui
    Abstract:

    CP32M is a newly designed peptide Fusion Inhibitor possessing potent anti-HIV activity, especially against T20-resistant HIV-1 strains. In this study, we show that CP32M can efficiently inhibit a large panel of diverse HIV-1 variants, including subtype B′, CRF07_BC, and CRF01_AE recombinants and naturally occurring or induced T20-resistant viruses. To elucidate its mechanism of action, we determined the crystal structure of CP32M complexed with its target sequence. Differing from its parental peptide, CP621-652, the 621VEWNEMT627 motif of CP32M folds into two α-helix turns at the N terminus of the pocket-binding domain, forming a novel layer in the six-helix bundle structure. Prominently, the residue Asn-624 of the 621VEWNEMT627 motif is engaged in the polar interaction with a hydrophilic ridge that borders the hydrophobic pocket on the N-terminal coiled coil. The original Inhibitor design of CP32M provides several intra- and salt bridge/hydrogen bond interactions favoring the stability of the helical conformation of CP32M and its interactions with N-terminal heptad repeat (NHR) targets. We identified a novel salt bridge between Arg-557 on the NHR and Glu-648 of CP32M that is critical for the binding of CP32M and resistance against the Inhibitor. Therefore, our data present important information for developing novel HIV-1 Fusion Inhibitors for clinical use.

  • biophysical property and broad anti hiv activity of albuvirtide a 3 maleimimidopropionic acid modified peptide Fusion Inhibitor
    PLOS ONE, 2012
    Co-Authors: Huihui Chong, Lifeng Cai, Xue Yao, Chao Zhang, Sheng Cui, Youchun Wang
    Abstract:

    Albuvirtide (ABT) is a 3-maleimimidopropionic acid (MPA)-modified peptide HIV Fusion Inhibitor that can irreversibly conjugate to serum albumin. Previous studies demonstrated its in vivo long half-life and potent anti-HIV activity. Here, we focused to characterize its biophysical properties and evaluate its antiviral spectrum. In contrast to T20 (Enfuvirtide, Fuzeon), ABT was able to form a stable α-helical conformation with the target sequence and block the Fusion-active six-helix bundle (6-HB) formation in a dominant-negative manner. It efficiently inhibited HIV-1 Env-mediated cell membrane Fusion and virus entry. A large panel of 42 HIV-1 pseudoviruses with different genotypes were constructed and used for the antiviral evaluation. The results showed that ABT had potent Inhibitory activity against the subtypes A, B and C that predominate the worldwide AIDS epidemics, and subtype B′, CRF07_BC and CRF01_AE recombinants that are currently circulating in China. Furthermore, ABT was also highly effective against HIV-1 variants resistant to T20. Taken together, our data indicate that the chemically modified peptide ABT can serve as an ideal HIV-1 Fusion Inhibitor.

Qian Wang - One of the best experts on this subject based on the ideXlab platform.

  • a pan coronavirus Fusion Inhibitor targeting the hr1 domain of human coronavirus spike
    Science Advances, 2019
    Co-Authors: Shuai Xia, Anurodh S Agrawal, Chiente K Tseng, Lanying Du, Abdullah Algaissi, Lei Yan, Wei Xu, Qian Wang, Wenjie Tan
    Abstract:

    Continuously emerging highly pathogenic human coronaviruses (HCoVs) remain a major threat to human health, as illustrated in past SARS-CoV and MERS-CoV outbreaks. The development of a drug with broad-spectrum HCoV Inhibitory activity would address this urgent unmet medical need. Although previous studies have suggested that the HR1 of HCoV spike (S) protein is an important target site for inhibition against specific HCoVs, whether this conserved region could serve as a target for the development of broad-spectrum pan-CoV Inhibitor remains controversial. Here, we found that peptide OC43-HR2P, derived from the HR2 domain of HCoV-OC43, exhibited broad Fusion Inhibitory activity against multiple HCoVs. EK1, the optimized form of OC43-HR2P, showed substantially improved pan-CoV Fusion Inhibitory activity and pharmaceutical properties. Crystal structures indicated that EK1 can form a stable six-helix bundle structure with both short α-HCoV and long β-HCoV HR1s, further supporting the role of HR1 region as a viable pan-CoV target site.

  • A Peptide-Based HIV-1 Fusion Inhibitor with Two Tail-Anchors and Palmitic Acid Exhibits Substantially Improved In Vitro and Ex Vivo Anti-HIV-1 Activity and Prolonged In Vivo Half-Life
    MDPI AG, 2019
    Co-Authors: Giselle Rasquinha, Qian Wang, Shibo Jiang
    Abstract:

    Enfuvirtide (T20) is the first U.S. FDA-approved HIV Fusion Inhibitor-based anti-HIV drug. Its clinical application is limited because of its low potency and short half-life. We previously reported that peptide HP23-E6-IDL, containing both N- and C-terminal anchor-tails, exhibited stronger potency and a better resistance profile than T20. Here we designed an analogous peptide, YIK, by introducing a mutation, T639I, and then a lipopeptide, YIK-C16, by adding palmitic acid (C16) at the C-terminus of YIK. We found that YIK-C16 was 4.4- and 3.6-fold more potent than HP23-E6-IDL and YIK against HIV-1IIIB infection and 13.3- and 10.5-fold more effective than HP23-E6-IDL and YIK against HIV-1Bal infection, respectively. Consistently, the ex vivo anti-HIV-1IIIB activity, as determined by the highest dilution-fold of the serum causing 50% inhibition of HIV-1 infection, of YIK-C16 in the sera of pretreated mice was remarkably higher than that of YIK or HP23-E6-IDL. The serum half-life (t1/2 = 5.9 h) of YIK-C16 was also significantly longer than that of YIK (t1/2 = 1.3 h) and HP23-E6-IDL (t1/2 = 1.0 h). These results suggest that the lipopeptide YIK-C16 shows promise for further development as a new anti-HIV drug with improved anti-HIV-1 activity and a prolonged half-life

  • Improved Pharmacological and Structural Properties of HIV Fusion Inhibitor AP3 over Enfuvirtide: Highlighting Advantages of Artificial Peptide Strategy.
    Scientific Reports, 2015
    Co-Authors: Xiaojie Zhu, Qian Wang, Yun Zhu, Zhiwu Sun, Qi Liu, Chao Wang
    Abstract:

    Enfuvirtide (T20), is the first HIV Fusion Inhibitor approved for treatment of HIV/AIDS patients who fail to respond to the current antiretroviral drugs. However, its clinical application is limited because of short half-life, drug resistance and cross-reactivity with the preexisting antibodies in HIV-infected patients. Using an artificial peptide strategy, we designed a peptide with non-native protein sequence, AP3, which exhibited potent antiviral activity against a broad spectrum of HIV-1 strains, including those resistant to T20, and had remarkably longer in vivo half-life than T20. While the preexisting antibodies in HIV-infected patients significantly suppressed T20’s antiviral activity, these antibodies neither recognized AP3, nor attenuated its anti-HIV-1 activity. Structurally different from T20, AP3 could fold into single-helix and interact with gp41 NHR. The two residues, Met and Thr, at the N-terminus of AP3 form a hook-like structure to stabilize interaction between AP3 and NHR helices. Therefore, AP3 has potential for further development as a new HIV Fusion Inhibitor with improved antiviral efficacy, resistance profile and pharmacological properties over enfuvirtide. Meanwhile, this study highlighted the advantages of artificially designed peptides, and confirmed that this strategy could be used in developing artificial peptide-based viral Fusion Inhibitors against HIV and other enveloped viruses.

  • nonneutralizing antibodies induced by the hiv 1 gp41 nhr domain gain neutralizing activity in the presence of the hiv Fusion Inhibitor enfuvirtide a potential therapeutic vaccine strategy
    Journal of Virology, 2015
    Co-Authors: Qian Wang, Shibo Jiang, Xiaojie Zhu
    Abstract:

    A key barrier against developing preventive and therapeutic human immunodeficiency virus (HIV) vaccines is the inability of viral envelope glycoproteins to elicit broad and potent neutralizing antibodies. However, in the presence of Fusion Inhibitor enfuvirtide, we show that the nonneutralizing antibodies induced by the HIV type 1 (HIV-1) gp41 N-terminal heptad repeat (NHR) domain (N63) exhibit potent and broad neutralizing activity against laboratory-adapted HIV-1 strains, including the drug-resistant variants, and primary HIV-1 isolates with different subtypes, suggesting the potential of developing gp41-targeted HIV therapeutic vaccines.

  • conjugation of a nonspecific antiviral sapogenin with a specific hiv Fusion Inhibitor a promising strategy for discovering new antiviral therapeutics
    Journal of Medicinal Chemistry, 2014
    Co-Authors: Chao Wang, Qian Wang, Xifeng Jiang, Lu Lu, Heya Na, Xiangpeng Li, Xiaoyu Xu, Fei Yu, Tianhong Zhang, Jinglai Li
    Abstract:

    Triterpene saponins are a major group of active components in natural products with nonspecific antiviral activities, while T20 peptide (enfuvirtide), which contains a helix zone-binding domain (HBD), is a gp41-specific HIV-1 Fusion Inhibitor. In this paper, we report the design, synthesis, and structure–activity relationship (SAR) of a group of hybrid molecules in which bioactive triterpene sapogenins were covalently attached to the HBD-containing peptides via click chemistry. We found that either the triterpenes or peptide part alone showed weak activity against HIV-1 Env-mediated cell–cell Fusion, while the hybrids generated a strong cooperative effect. Among them, P26–BApc exhibited anti-HIV-1 activity against both T20-sensitive and -resistant HIV-1 strains and improved pharmacokinetic properties. These results suggest that this scaffold design is a promising strategy for developing new HIV-1 Fusion Inhibitors and possibly novel antiviral therapeutics against other viruses with class I Fusion proteins.

Xiaohui Ding - One of the best experts on this subject based on the ideXlab platform.

  • structural and functional characterization of hiv 1 cell Fusion Inhibitor t20
    AIDS, 2019
    Co-Authors: Huihui Chong, Xiaohui Ding, Yuanmei Zhu, Sheng Cui, Xiujuan Zhang, Xinquan Wang
    Abstract:

    Objective The peptide drug T20 (enfuvirtide), derived from the C-terminal heptad repeat region of HIV-1 gp41, is the only membrane Fusion Inhibitor available for treatment of viral infection; however, its mechanism of action remains elusive and its structural basis is lacking. Design We focused on determining the crystal structure of T20 in complex with N39, a target mimic peptide derived from the N-terminal heptad repeat region of gp41. On the basis of the structural information, the mechanisms of action of T20 and its resistance were further characterized. Methods A panel of peptides was synthesized. The T20/N39 complex was assembled for crystallization studies. Circular dichroism spectroscopy, isothermal titration calorimetry (ITC), native polyacrylamide gel electrophoresis (N-PAGE), and mutational analysis were applied to analyze the structural and functional properties. Results A crystal structure of six-helical bundle (6-HB) structure formed by T20 and N39 was determined with a resolution limit of 2.3 A, which revealed the critical intrahelical and interhelical interactions underlying the mechanism of action of T20 and its resistance mutations. Although the structural properties in the C-terminal tryptophan-rich motif (TRM) of T20 and the Fusion peptide proximal region (FPPR) of N39 could not be finely defined by the structure, the data from biophysical and mutational analyses verified the essential roles of the TRM and FPPR motifs for the binding and Inhibitory activities of T20. Conclusion For the first time, our studies provide a structural basis of T20, which help our understanding on the mechanisms of HIV-1 Fusion and its inhibition.

  • molecular mechanism of hiv 1 resistance to sifuvirtide a clinical trial approved membrane Fusion Inhibitor
    Journal of Biological Chemistry, 2018
    Co-Authors: Xiaohui Ding, Huihui Chong, Yuanmei Zhu, Zixuan Liu, Huanmian Wei, Sheng Cui
    Abstract:

    Host cell infection with HIV-1 requires Fusion of viral and cell membranes. Sifuvirtide (SFT) is a peptide-based HIV-1 Fusion Inhibitor approved for phase III clinical trials in China. Here, we focused on characterizing HIV-1 variants highly resistant to SFT to gain insight into the molecular resistance mechanism. Three primary substitutions (V38A, A47I, and Q52R) located at the Inhibitor-binding site of HIV-1's envelope protein (Env) and one secondary substitution (N126K) located at the C-terminal heptad repeat region of the viral protein gp41, which is part of the envelope, conferred high SFT resistance and cross-resistance to the anti-HIV-1 drug T20 and the template peptide C34. Interestingly, SFT's resistance profile could be dramatically improved with an M-T hook structure-modified SFT (MTSFT) and with short-peptide Inhibitors that mainly target the gp41 pocket (2P23 and its lipid derivative LP-19). We found that the V38A and Q52R substitutions reduce the binding stabilities of SFT, C34, and MTSFT, but they had no effect on the binding of 2P23 and LP-19; in sharp contrast, the A47I substitution enhanced Fusion Inhibitor binding. Furthermore, the primary resistance substitutions impaired Env-mediated membrane Fusion and cell entry and changed the conformation of the gp41 core structure. Importantly, whereas the V38A and Q52R substitutions disrupted the N-terminal helix of gp41, a single A47I substitution greatly enhanced its thermostability. Taken together, our results provide crucial structural insights into the mechanism of HIV-1 resistance to gp41-dependent Fusion Inhibitors, which may inform the development of additional anti-HIV drugs.

  • exceptional potency and structural basis of a t1249 derived lipopeptide Fusion Inhibitor against hiv 1 hiv 2 and simian immunodeficiency virus
    Journal of Biological Chemistry, 2018
    Co-Authors: Xiujuan Zhang, Huihui Chong, Xiaohui Ding, Xinquan Wang, Jinsheng He, Yuxian He
    Abstract:

    : Enfuvirtide (T20) is the only viral Fusion Inhibitor approved for clinical use, but it has relatively weak anti-HIV activity and easily induces drug resistance. In succession to T20, T1249 has been designed as a 39-mer peptide composed of amino acid sequences derived from HIV-1, HIV-2, and simian immunodeficiency virus (SIV); however, its development has been suspended due to formulation difficulties. We recently developed a T20-based lipopeptide (LP-40) showing greatly improved pharmaceutical properties. Here, we generated a T1249-based lipopeptide, termed LP-46, by replacing its C-terminal tryptophan-rich sequence with fatty acid. As compared with T20, T1249, and LP-40, the truncated LP-46 (31-mer) had dramatically increased activities in inhibiting a large panel of HIV-1 subtypes, with IC50 values approaching low picomolar concentrations. Also, LP-46 was an exceptionally potent Inhibitor against HIV-2, SIV, and T20-resistant variants, and it displayed obvious synergistic effects with LP-40. Furthermore, we showed that LP-46 had increased helical stability and binding affinity with the target site. The crystal structure of LP-46 in complex with a target surrogate revealed its critical binding motifs underlying the mechanism of action. Interestingly, it was found that the introduced pocket-binding domain in LP-46 did not interact with the gp41 pocket as expected; instead, it adopted a mode similar to that of LP-40. Therefore, our studies have provided an exceptionally potent and broad Fusion Inhibitor for developing new anti-HIV drugs, which can also serve as a tool to exploit the mechanisms of viral Fusion and inhibition.

  • enfuvirtide t20 based lipopeptide is a potent hiv 1 cell Fusion Inhibitor implications for viral entry and inhibition
    Journal of Virology, 2017
    Co-Authors: Xiaohui Ding, Huihui Chong, Yuanmei Zhu, Huamian Wei, Xiujuan Zhang, Xinquan Wang
    Abstract:

    The peptide drug enfuvirtide (T20) is the only viral Fusion Inhibitor used in combination therapy for HIV-1 infection, but it has relatively low antiviral activity and easily induces drug resistance. Emerging studies demonstrate that lipopeptide-based Fusion Inhibitors, such as LP-11 and LP-19, which mainly target the gp41 pocket site, have greatly improved antiviral potency and in vivo stability. In this study, we focused on developing a T20-based lipopeptide Inhibitor that lacks pocket-binding sequence and targets a different site. First, the C-terminal tryptophan-rich motif (TRM) of T20 was verified to be essential for its target binding and inhibition; then, a novel lipopeptide, termed LP-40, was created by replacing the TRM with a fatty acid group. LP-40 showed markedly enhanced binding affinity for the target site and dramatically increased Inhibitory activity on HIV-1 membrane Fusion, entry, and infection. Unlike LP-11 and LP-19, which required a flexible linker between the peptide sequence and the lipid moiety, addition of a linker to LP-40 sharply reduced its potency, implying different binding modes with the extended N-terminal helices of gp41. Also, interestingly, LP-40 showed more potent activity than LP-11 in inhibiting HIV-1 Env-mediated cell-cell Fusion while it was less active than LP-11 in inhibiting pseudovirus entry, and the two Inhibitors displayed synergistic antiviral effects. The crystal structure of LP-40 in complex with a target peptide revealed their key binding residues and motifs. Combined, our studies have not only provided a potent HIV-1 Fusion Inhibitor, but also revealed new insights into the mechanisms of viral inhibition.IMPORTANCE T20 is the only membrane Fusion Inhibitor available for treatment of viral infection; however, T20 requires high doses and has a low genetic barrier for resistance, and its Inhibitory mechanism and structural basis remain unclear. Here, we report the design of LP-40, a T20-based lipopeptide Inhibitor that has greatly improved anti-HIV activity and is a more potent Inhibitor of cell-cell Fusion than of cell-free virus infection. The binding modes of two classes of membrane-anchoring lipopeptides (LP-40 and LP-11) verify the current Fusion model in which an extended prehairpin structure bridges the viral and cellular membranes, and their complementary effects suggest a vital strategy for combination therapy of HIV-1 infection. Moreover, our understanding of the mechanism of action of T20 and its derivatives benefits from the crystal structure of LP-40.

  • a lipopeptide hiv 1 2 Fusion Inhibitor with highly potent in vitro ex vivo and in vivo antiviral activity
    Journal of Virology, 2017
    Co-Authors: Huihui Chong, Jing Xue, Shengwen Xiong, Zhe Cong, Xiaohui Ding, Yuanmei Zhu, Zixuan Liu, Ting Chen, Yifan Feng, Yan Guo
    Abstract:

    Peptides derived from the C-terminal heptad repeat (CHR) region of the human immunodeficiency virus type 1 (HIV-1) fusogenic protein gp41 are potent viral entry Inhibitors, and currently, enfuvirtide (T-20) is the only one approved for clinical use; however, emerging drug resistance largely limits its efficacy. In this study, we generated a novel lipopeptide Inhibitor, named LP-19, by integrating multiple design strategies, including an N-terminal M-T hook structure, an HIV-2 sequence, intrahelical salt bridges, and a membrane-anchoring lipid tail. LP-19 showed stable binding affinity and highly potent, broad, and long-lasting antiviral activity. In in vitro studies, LP-19 efficiently inhibited HIV-1-, HIV-2-, and simian immunodeficiency virus (SIV)-mediated cell Fusion, viral entry, and infection, and it was highly active against diverse subtypes of primary HIV-1 isolates and Inhibitor-resistant mutants. Ex vivo studies demonstrated that LP-19 exhibited dramatically increased anti-HIV activity and an extended half-life in rhesus macaques. In short-term monotherapy, LP-19 reduced viral loads to undetectable levels in acutely and chronically simian-human immunodeficiency virus (SHIV)-infected monkeys. Therefore, this study offers an ideal HIV-1/2 Fusion Inhibitor for clinical development and emphasizes the importance of the viral Fusion step as a drug target.IMPORTANCE The peptide drug T-20 is the only viral Fusion Inhibitor in the clinic, which is used for combination therapy of HIV-1 infection; however, it requires a high dosage and easily induces drug resistance, calling for a new drug with significantly improved pharmaceutical profiles. Here, we have developed a short-lipopeptide-based Fusion Inhibitor, termed LP-19, which mainly targets the conserved gp41 pocket site and shows highly potent Inhibitory activity against HIV-1, HIV-2, and even SIV isolates. LP-19 exhibits dramatically increased antiviral activity and an extended half-life in rhesus macaques, and it has potent therapeutic efficacy in SHIV-infected monkeys, highlighting its high potential as a new viral Fusion Inhibitor for clinical use.

Related terms

Fusion Inhibitor - 15 days free trial to Access Experts & Abstracts