1
|
Targeting CXCR4 and CD47 Receptors: An Overview of New and Old Molecules for a Biological Personalized Anticancer Therapy. Int J Mol Sci 2022; 23:ijms232012499. [PMID: 36293358 PMCID: PMC9604048 DOI: 10.3390/ijms232012499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/14/2022] [Accepted: 10/14/2022] [Indexed: 11/26/2022] Open
Abstract
Biological therapy, with its multifaceted applications, has revolutionized the treatment of tumors, mainly due to its ability to exclusively target cancer cells and reduce the adverse effects on normal tissues. This review focuses on the therapies targeting the CXCR4 and CD47 receptors. We surveyed the results of early clinical trials testing compounds classified as nonpeptides, small peptides, CXCR4 antagonists or specific antibodies whose activity reduces or completely blocks the intracellular signaling pathways and cell proliferation. We then examined antibodies and fusion proteins against CD47, the receptor that acts as a “do not eat me” signal to phagocytes escaping immune surveillance. Despite these molecules being tested in early clinical trials, some drawbacks are emerging that impair their use in practice. Finally, we examined the ImmunoGenic Surrender mechanism that involves crosstalk and co-internalization of CXCR4 and CD47 upon engagement of CXCR4 by ligands or other molecules. The favorable effect of such compounds is dual as CD47 surface reduction impact on the immune response adds to the block of CXCR4 proliferative potential. These results suggest that a combination of different therapeutic approaches has more beneficial effects on patients’ survival and may pave the way for new accomplishments in personalized anticancer therapy.
Collapse
|
2
|
Antiviral Effects of Animal Toxins: Is There a Way to Drugs? Int J Mol Sci 2022; 23:ijms23073634. [PMID: 35408989 PMCID: PMC8998278 DOI: 10.3390/ijms23073634] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/23/2022] [Accepted: 03/24/2022] [Indexed: 12/18/2022] Open
Abstract
Viruses infect all types of organisms, causing viral diseases, which are very common in humans. Since viruses use the metabolic pathways of their host cells to replicate, they are difficult to eradicate without affecting the cells. The most effective measures against viral infections are vaccinations and antiviral drugs, which selectively inhibit the viral replication cycle. Both methods have disadvantages, which requires the development of new approaches to the treatment of viral diseases. In the study of animal venoms, it was found that, in addition to toxicity, venoms exhibit other types of biological activity, including an antiviral one, the first mention of which dates back to middle of the last century, but detailed studies of their antiviral activity have been conducted over the past 15 years. The COVID-19 pandemic has reinforced these studies and several compounds with antiviral activity have been identified in venoms. Some of them are very active and can be considered as the basis for antiviral drugs. This review discusses recent antiviral studies, the found compounds with high antiviral activity, and the possible mechanisms of their action. The prospects for using the animal venom components to create antiviral drugs, and the expected problems and possible solutions are also considered.
Collapse
|
3
|
Roy S, Sarkhel S, Bisht D, Hanumantharao SN, Rao S, Jaiswal A. Antimicrobial Mechanisms of Biomaterials: From Macro to Nano. Biomater Sci 2022; 10:4392-4423. [DOI: 10.1039/d2bm00472k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Overcoming the global concern of antibiotic resistance is one of the biggest challenge faced by scientists today and the key to tackle this issue of emerging infectious diseases is the...
Collapse
|
4
|
Kuroki A, Tay J, Lee GH, Yang YY. Broad-Spectrum Antiviral Peptides and Polymers. Adv Healthc Mater 2021; 10:e2101113. [PMID: 34599850 DOI: 10.1002/adhm.202101113] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 09/13/2021] [Indexed: 12/18/2022]
Abstract
As the human cost of the pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still being witnessed worldwide, the development of broad-spectrum antiviral agents against emerging and re-emerging viruses is seen as a necessity to hamper the spread of infections. Various targets during the viral life-cycle can be considered to inhibit viral infection, from viral attachment to viral fusion or replication. Macromolecules represent a particularly attractive class of therapeutics due to their multivalency and versatility. Although several antiviral macromolecules hold great promise in clinical applications, the emergence of resistance after prolonged exposure urges the need for improved solutions. In the present article, the recent advancement in the discovery of antiviral peptides and polymers with diverse structural features and antiviral mechanisms is reviewed. Future perspectives, such as, the development of virucidal peptides/polymers and their coatings against SARS-CoV-2 infection, standardization of antiviral testing protocols, and use of artificial intelligence or machine learning as a tool to accelerate the discovery of antiviral macromolecules, are discussed.
Collapse
Affiliation(s)
- Agnès Kuroki
- Yong Loo Lin School of Medicine National University of Singapore Singapore 117597 Singapore
- Institute of Bioengineering and Bioimaging 31 Biopolis Ways, The Nanos Singapore 138669 Singapore
| | - Joyce Tay
- Institute of Bioengineering and Bioimaging 31 Biopolis Ways, The Nanos Singapore 138669 Singapore
| | - Guan Huei Lee
- Yong Loo Lin School of Medicine National University of Singapore Singapore 117597 Singapore
| | - Yi Yan Yang
- Institute of Bioengineering and Bioimaging 31 Biopolis Ways, The Nanos Singapore 138669 Singapore
| |
Collapse
|
5
|
Li H, Ali Z, Liu X, Jiang L, Tang Y, Dai J. Expression of recombinant tachyplesin I in Pichia pastoris. Protein Expr Purif 2019; 157:50-56. [PMID: 30711625 DOI: 10.1016/j.pep.2019.01.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/20/2019] [Accepted: 01/30/2019] [Indexed: 11/19/2022]
Abstract
The development of antibiotic-resistant bacteria has become a major public health problem, prompting the search for alternative solutions. Tachyplesin I (TP-I) is an antimicrobial peptide, which exhibits potent and broad-spectrum activities against bacteria, fungi, viruses, and tumor cells. However, limited amounts of TP-I produced in horseshoe crab restrict its large-scale use. In order to solve this problem, a eukaryotic expression system of Pichia pastoris with high TP-I expression was constructed by gene engineering. To achieve high expression of TP-I, 74 amino acid-long peptide (4TP-1) was designed containing 4 copies of TP-I, and specific cleavage sites for pancreatic elastase (-Ala↓ or -Gly↓) and carboxypeptidase A (cleaves C terminal amino acid); these cleavage sites for enzymes were located between the four copies of TP-I. The gene sequence for the designed peptide was synthesized taking into consideration codon preferences for P. pastoris, and cloned into the highly efficient expression vector pGAPZα B. Host Pichia pastoris strain GS115 cells were transfected by the constructed expression vector pGAPZα B-4tp-I by electroporation. Tricine-SDS-PAGE electrophoresis was carried out to detect the expression of target peptides in the fermentation medium. This analysis showed a protein band of 3.3 kDa, identical to that of chemically synthesized TP-I, verifying that successful synthesis and secretion of TP-I by genetically engineered P. pastoris. The concentration of TP-I in the fermentation broth was 27.24-29.53 mg/L. High-resolution mass spectrometry analysis documented that the TP-I monomer had the same molecular weight, 2262.85, as the designed 17-amino acid sequence. The recombinant TP-I peptide displayed different levels of bactericidal activity against Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus. Thus, the present study demonstrated the feasibility of achieving high levels of expression of TP-I in P. pastoris.
Collapse
Affiliation(s)
- Hanmei Li
- Shenzhen Key Laboratory of Fermentation, Purification and Analysis, Shenzhen Polytechnic, Shenzhen, 518055, China
| | - Zeeshan Ali
- Shenzhen Key Laboratory of Fermentation, Purification and Analysis, Shenzhen Polytechnic, Shenzhen, 518055, China; School of Medicine, Southeast University, Nanjing, 210009, China
| | - Xiaolong Liu
- Shenzhen Key Laboratory of Fermentation, Purification and Analysis, Shenzhen Polytechnic, Shenzhen, 518055, China
| | - Li Jiang
- School of Medicine, Southeast University, Nanjing, 210009, China
| | - Yongjun Tang
- Shenzhen Key Laboratory of Fermentation, Purification and Analysis, Shenzhen Polytechnic, Shenzhen, 518055, China.
| | - Jianguo Dai
- Shenzhen Key Laboratory of Fermentation, Purification and Analysis, Shenzhen Polytechnic, Shenzhen, 518055, China.
| |
Collapse
|
6
|
Mandal SM, Roy A, Ghosh AK, Hazra TK, Basak A, Franco OL. Challenges and future prospects of antibiotic therapy: from peptides to phages utilization. Front Pharmacol 2014; 5:105. [PMID: 24860506 PMCID: PMC4027024 DOI: 10.3389/fphar.2014.00105] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/22/2014] [Indexed: 12/30/2022] Open
Abstract
Bacterial infections are raising serious concern across the globe. The effectiveness of conventional antibiotics is decreasing due to global emergence of multi-drug-resistant (MDR) bacterial pathogens. This process seems to be primarily caused by an indiscriminate and inappropriate use of antibiotics in non-infected patients and in the food industry. New classes of antibiotics with different actions against MDR pathogens need to be developed urgently. In this context, this review focuses on several ways and future directions to search for the next generation of safe and effective antibiotics compounds including antimicrobial peptides, phage therapy, phytochemicals, metalloantibiotics, lipopolysaccharide, and efflux pump inhibitors to control the infections caused by MDR pathogens.
Collapse
Affiliation(s)
- Santi M Mandal
- Central Research Facility, Department of Chemistry and Department of Biotechnology, Indian Institute of Technology Kharagpur Kharagpur, India
| | - Anupam Roy
- Central Research Facility, Department of Chemistry and Department of Biotechnology, Indian Institute of Technology Kharagpur Kharagpur, India
| | - Ananta K Ghosh
- Central Research Facility, Department of Chemistry and Department of Biotechnology, Indian Institute of Technology Kharagpur Kharagpur, India
| | - Tapas K Hazra
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Texas Medical Branch at Galveston Galveston, TX, USA
| | - Amit Basak
- Central Research Facility, Department of Chemistry and Department of Biotechnology, Indian Institute of Technology Kharagpur Kharagpur, India
| | - Octavio L Franco
- Centro de Análises Proteômicas e Bioquímicas, Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília Brasilia, Brazil
| |
Collapse
|
7
|
Oishi S, Fujii N. Peptide and peptidomimetic ligands for CXC chemokine receptor 4 (CXCR4). Org Biomol Chem 2012; 10:5720-31. [DOI: 10.1039/c2ob25107h] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
8
|
Singh IP, Chauthe SK. Small molecule HIV entry inhibitors: Part I. Chemokine receptor antagonists: 2004 – 2010. Expert Opin Ther Pat 2011; 21:227-69. [DOI: 10.1517/13543776.2011.542412] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
9
|
Therapeutic approaches using host defence peptides to tackle herpes virus infections. Viruses 2009; 1:939-64. [PMID: 21994576 PMCID: PMC3185547 DOI: 10.3390/v1030939] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 10/11/2009] [Accepted: 11/16/2009] [Indexed: 01/07/2023] Open
Abstract
One of the most common viral infections in humans is caused by herpes simplex virus (HSV). It can easily be treated with nucleoside analogues (e.g., acyclovir), but resistant strains are on the rise. Naturally occurring antimicrobial peptides have been demonstrated to possess antiviral activity against HSV. New evidence has also indicated that these host defence peptides are able to selectively stimulate the innate immune system to fight of infections. This review will focus on the anti-HSV activity of such peptides (both natural and synthetic), describe their mode of action and their clinical potential.
Collapse
|
10
|
Tilton JC, Doms RW. Entry inhibitors in the treatment of HIV-1 infection. Antiviral Res 2009; 85:91-100. [PMID: 19683546 DOI: 10.1016/j.antiviral.2009.07.022] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 07/21/2009] [Accepted: 07/30/2009] [Indexed: 11/15/2022]
Abstract
Infection of target cells by HIV is a complex, multi-stage process involving attachment to host cells and CD4 binding, coreceptor binding, and membrane fusion. Drugs that block HIV entry are collectively known as entry inhibitors, but comprise a complex group of drugs with multiple mechanisms of action depending on the stage of the entry process at which they act. Two entry inhibitors, maraviroc and enfuvirtide, have been approved for the treatment of HIV-1 infection, and a number of agents are in development. This review covers the entry inhibitors and their use in the management of HIV-1 infection. This article forms part of a special issue of Antiviral Research marking the 25th anniversary of antiretroviral drug discovery and development, Vol 85, issue 1, 2010.
Collapse
Affiliation(s)
- John C Tilton
- Department of Microbiology, University of Pennsylvania, 301C Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, United States.
| | | |
Collapse
|
11
|
Qian K, Morris-Natschke SL, Lee KH. HIV entry inhibitors and their potential in HIV therapy. Med Res Rev 2009; 29:369-93. [PMID: 18720513 DOI: 10.1002/med.20138] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This review discusses recent progress in the development of anti-HIV agents targeting the viral entry process. The three main classes (attachment inhibitors, co-receptor binding inhibitors, and fusion inhibitors) are further broken down by specific mechanism of action and structure. Many of these inhibitors are in advanced clinical trials, including the HIV maturation inhibitor bevirimat, from the authors' laboratories. In addition, the CCR5 inhibitor maraviroc has recently been FDA-approved. Possible roles for these agents in anti-HIV therapy, including treatment of virus resistant to current drugs, are also discussed.
Collapse
Affiliation(s)
- Keduo Qian
- Natural Products Research Laboratories, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | | | | |
Collapse
|
12
|
Abstract
Antimicrobial host defense peptides are produced by all complex organisms as well as some microbes and have diverse and complex antimicrobial activities. Collectively these peptides demonstrate a broad range of antiviral and antibacterial activities and modes of action, and it is important to distinguish between direct microbicidal and indirect activities against such pathogens. The structural requirements of peptides for antiviral and antibacterial activities are evaluated in light of the diverse set of primary and secondary structures described for host defense peptides. Peptides with antifungal and antiparasitic activities are discussed in less detail, although the broad-spectrum activities of such peptides indicate that they are important host defense molecules. Knowledge regarding the relationship between peptide structure and function as well as their mechanism of action is being applied in the design of antimicrobial peptide variants as potential novel therapeutic agents.
Collapse
Affiliation(s)
- Håvard Jenssen
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Lower Mall Research Station, 232-2259 Lower Mall, Vancouver, British Columbia V6T 1Z4, Canada
| | | | | |
Collapse
|
13
|
Ester Derivatives of Nucleoside Inhibitors of Reverse Transcriptase: 2. Molecular Systems for the Combined Therapy with 3′-Azido-3′-Deoxythymidine and 2′,3′-Didehydro-3′-Deoxythymidine. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2005. [DOI: 10.1007/s11171-005-0057-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
14
|
Zaitseva M, Peden K, Golding H. HIV coreceptors: role of structure, posttranslational modifications, and internalization in viral-cell fusion and as targets for entry inhibitors. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1614:51-61. [PMID: 12873765 DOI: 10.1016/s0005-2736(03)00162-7] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The human immunodeficiency virus (HIV) envelope glycoprotein forms trimers on the virion surface, with each monomer consisting of two subunits, gp120 and gp41. The gp120 envelope component binds to CD4 on target cells and undergoes conformational changes that allow gp120 to interact with certain G-protein-coupled receptors (GPCRs) on the same target membranes. The GPCRs that function as HIV coreceptors were found to be chemokine receptors. The primary coreceptors are CCR5 and CXCR4, but several other chemokine receptors were identified as "minor coreceptors", indicating their ability support entry of some HIV strains in tissue cultures. Formation of the tri-molecular complexes stabilizes virus binding and triggers a series of conformational changes in gp41 that facilitate membrane fusion and viral cell entry. Concerted efforts are underway to decipher the specific interactions between gp120/CD4, gp120/coreceptors, and their contributions to the subsequent membrane fusion process. It is hoped that some of the transient conformational intermediates in gp120 and gp41 would serve as targets for entry inhibitors. In addition, the CD4 and coreceptors are primary targets for several classes of inhibitors currently under testing. Our review summarizes the current knowledge on the interactions of HIV gp120 with its receptor and coreceptors, and the important properties of the chemokine receptors and their regulation in primary target cells. We also summarize the classes of coreceptor inhibitors under development.
Collapse
Affiliation(s)
- Marina Zaitseva
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, 8800 Rockville Pike, Bethesda, MD 20892, USA
| | | | | |
Collapse
|
15
|
Ma J, Kennedy-Stoskopf S, Jaynes JM, Thurmond LM, Tompkins WA. Inhibitory activity of synthetic peptide antibiotics on feline immunodeficiency virus infectivity in vitro. J Virol 2002; 76:9952-61. [PMID: 12208971 PMCID: PMC136481 DOI: 10.1128/jvi.76.19.9952-9961.2002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Natural peptide antibiotics are part of host innate immunity against a wide range of microbes, including some viruses. Synthetic peptides modeled after natural peptide antibiotics interfere with microbial membranes and are termed peptidyl membrane-interactive molecules (peptidyl-MIM [Demegen Inc, Pittsburgh, Pa.]). Sixteen peptidyl-MIM candidates were tested for activity against feline immunodeficiency virus (FIV) on infected CrFK cells. Three of them (D4E1, DC1, and D1D6) showed potent anti-FIV activity in chronically infected CrFK cells as measured by decreased reverse transcriptase (RT) activity, having 50% inhibitory concentrations of 0.46, 0.75, and 0.94 micro M, respectively, which were approximately 10 times lower than their direct cytotoxic concentrations. Treatment of chronically infected CrFK cells with 2 micro M D4E1 for 3 days completely reversed virus-induced cytopathic effect. Immunofluorescence revealed reduced p26 staining in these cells. Treatment of chronically infected CrFK cells with 2 micro M D4E1 suppressed virus production ( approximately 50%) for up to 7 days, The virions from the D4E1-treated culture had impaired infectivity, as measured by the 50% tissue culture infectious dose and nested PCR analysis of proviral DNA. However, these noninfectious virions were able to bind and internalize, suggesting a defect at some postentry step. After chronically infected CrFK cells were treated with D4E1 for 24 h, increased cell-associated mature p26 Gag and decreased extracellular virus-associated p26 Gag were observed by Western blot analysis, suggesting that virus assembly and/or release may be blocked by D4E1 treatment, whereas virus binding, penetration, RNA synthesis, and protein synthesis appear to be unaffected. Synthetic peptide antibiotics may be useful tools in the search for antiviral drugs having a wide therapeutic window for host cells.
Collapse
Affiliation(s)
- Jia Ma
- Department of Microbiology, Pathology and Parasitology, North Carolina State University, Raleigh, North Carolina, USA.
| | | | | | | | | |
Collapse
|
16
|
Abstract
Although chemokines were originally defined as host defense proteins it is now clear that their repertoire of functions extend well beyond this role. For example chemokines such as MGSA have growth regulatory properties while members of the CXC chemokine family can be mediators or inhibitors of angiogenesis and may be important targets for oncology. Recent work shows that the chemokine receptor CXCR4 and its cognate ligand SDF play important roles in the development of the immune, circulatory and central nervous systems. In addition, chemokine receptors play an important role in the pathogenesis of the AIDS virus, HIV-1. Taken together these findings expand the biological importance of chemokines from that of simple immune modulators to a much broader biological role than was at first appreciated and these and other properties of the chemokine receptor family are discussed in detail in this review.
Collapse
Affiliation(s)
- R Horuk
- Department of Immunology, Berlex Bioscience, 15049 San Pablo Avenue, Richmond, CA 94804, USA.
| |
Collapse
|
17
|
Abstract
The authors have discovered a highly selective CXCR4 antagonist, T22 ([Tyr5,12, Lys7]-polyphemusin II), and its shortened potent analogs, T140 and TC14012, which strongly inhibit the T-cell line-tropic HIV-1 (X4-HIV-1) infection through their specific binding to a chemokine receptor, CXCR4. CXCR4 is a major coreceptor (second receptor) for the entry of X4-HIV-1 into T-cells. These peptides have been found through the structure-activity relationship (SAR) study on tachyplesins and polyphemusins, which function as self-defense peptides of horseshoe crabs with immature immune systems. T140 and TC14012 showed the highest level of anti-HIV activity and antagonism of target cell entry by X4-HIV-1 among all the CXCR4 antagonists that have been reported to date. Additionally, bifunctional anti-HIV agents based on the specific CXCR4 antagonists (T140 analogs)-3'-azido-3'-deoxythymidine (AZT) conjugation have been synthesized and evaluated, since T140 analogs can possibly work as a carrier of AZT targeting T-cells due to their specific affinity for CXCR4 on T-cells. T22 have two disulfide bonds and a Trp residue in the molecule. In connection with this study, novel facile and side-reaction-free methodologies for disulfide bond formation have been established for the increase of the efficiency of SAR studies. Furthermore, the completely stereocontrolled synthetic process for a couple of (E)-alkene dipeptide isosteres starting from L-amino acid has been established in order to facilitate nonpeptidylation studies on peptide-lead candidates. In this review, the authors wish to summarize our recent research on the development of specific antagonists against the HIV second receptor CXCR4, involving studies on the establishment of efficient methodologies for the facile synthesis of peptides and peptide mimetics.
Collapse
Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
18
|
Conformational analysis on anti-HIV-1 peptide T22 ([Tyr5,12,Lys7]-polyphemusin II). CHINESE SCIENCE BULLETIN-CHINESE 2001. [DOI: 10.1007/bf02900651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
19
|
Li P, Chan HC, He B, So SC, Chung YW, Shang Q, Zhang YD, Zhang YL. An antimicrobial peptide gene found in the male reproductive system of rats. Science 2001; 291:1783-5. [PMID: 11230693 DOI: 10.1126/science.1056545] [Citation(s) in RCA: 179] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Little is known about the innate defense mechanisms of the male reproductive tract. We cloned a 385-base pair complementary DNA and its genomic DNA named Bin1b that is exclusively expressed in the caput region of the rat epididymis and that is responsible for sperm maturation, storage, and protection. Bin1b exhibits structural characteristics and antimicrobial activity similar to that of cationic antimicrobial peptides, beta-defensins. Bin1b is maximally expressed when the rats are sexually mature and can be up-regulated by inflammation. Bin1b appears to be a natural epididymis-specific antimicrobial peptide that plays a role in reproductive tract host defense and male fertility.
Collapse
Affiliation(s)
- P Li
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, 320, Yue-Yang Road, Shanghai 200031, China
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Abstract
A large variety of natural products have been described as anti-HIV agents, and for a portion thereof the target of interaction has been identified. Cyanovirin-N, a 11-kDa protein from Cyanobacterium (blue-green alga) irreversibly inactivates HIV and also aborts cell-to-cell fusion and transmission of HIV, due to its high-affinity interaction with gp120. Various sulfated polysaccharides extracted from seaweeds (i.e., Nothogenia fastigiata, Aghardhiella tenera) inhibit the virus adsorption process. Ingenol derivatives may inhibit virus adsorption at least in part through down-regulation of CD4 molecules on the host cells. Inhibition of virus adsorption by flavanoids such as (-)epicatechin and its 3-O-gallate has been attributed to an irreversible interaction with gp120 (although these compounds are also known as reverse transcriptase inhibitors). For the triterpene glycyrrhizin (extracted from the licorice root Glycyrrhiza radix) the mode of anti-HIV action may at least in part be attributed to interference with virus-cell binding. The mannose-specific plant lectins from Galanthus, Hippeastrum, Narcissus, Epipac tis helleborine, and Listera ovata, and the N-acetylgl ucosamine-specific lectin from Urtica dioica would primarily be targeted at the virus-cell fusion process. Various other natural products seem to qualify as HIV-cell fusion inhibitors: the siamycins [siamycin I (BMY-29304), siamycin II (RP 71955, BMY 29303), and NP-06 (FR901724)] which are tricyclic 21-amino-acid peptides isolated from Streptomyces spp that differ from one another only at position 4 or 17 (valine or isoleucine in each case); the betulinic acid derivative RPR 103611, and the peptides tachyplesin and polyphemusin which are highly abundant in hemocyte debris of the horseshoe crabs Tachypleus tridentatus and Limulus polyphemus, i.e., the 18-amino-acid peptide T22 from which T134 has been derived. Both T22 and T134 have been shown to block T-tropic X4 HIV-1 strains through a specific antagonism with the HIV corecept or CXCR4. A number of natural products have been reported to interact with the reverse transcriptase, i.e., baicalin, avarol, avarone, psychotrine, phloroglucinol derivatives, and, in particular, calanolides (from the tropical rainforest tree, Calophyllum lanigerum) and inophyllums (from the Malaysian tree, Calophyllum inophyllum). The natural marine substance illimaquinone would be targeted at the RNase H function of the reverse transcriptase. Curcumin (diferuloylmethane, from turmeric, the roots/rhizomes of Curcuma spp), dicaffeoylquinic and dicaffeoylt artaric acids, L-chicoric acid, and a number of fungal metabolites (equisetin, phomasetin, oteromycin, and integric acid) have all been proposed as HIV-1 integrase inhibitors. Yet, we have recently shown that L-c hicoric acid owes its anti-HIV activity to a specific interaction with the viral envelope gp120 rather than integrase. A number of compounds would be able to inhibit HIV-1 gene expression at the transcription level: the flavonoid chrysin (through inhibition of casein kinase II, the antibacter ial peptides melittin (from bee venom) and cecropin, and EM2487, a novel substance produced by Streptomyces. (ABSTRACT TRUNCATED)
Collapse
Affiliation(s)
- E De Clercq
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium.
| |
Collapse
|
21
|
Abstract
Antibiotic peptides are a key component of the innate immune systems of most multicellular organisms. Despite broad divergences in sequence and taxonomy, most antibiotic peptides share a common mechanism of action, i.e., membrane permeabilization of the pathogen. This review provides a general introduction to the subject, with emphasis on aspects such as structural types, post-translational modifications, mode of action or mechanisms of resistance. Some of these questions are treated in depth in other reviews in this issue. The review also discusses the role of antimicrobial peptides in nature, including several pathological conditions, as well as recent accounts of their application at the preclinical level.
Collapse
Affiliation(s)
- D Andreu
- Department of Organic Chemistry, Universitat de Barcelona, Spain.
| | | |
Collapse
|
22
|
Murakami T, Zhang TY, Koyanagi Y, Tanaka Y, Kim J, Suzuki Y, Minoguchi S, Tamamura H, Waki M, Matsumoto A, Fujii N, Shida H, Hoxie JA, Peiper SC, Yamamoto N. Inhibitory mechanism of the CXCR4 antagonist T22 against human immunodeficiency virus type 1 infection. J Virol 1999; 73:7489-96. [PMID: 10438838 PMCID: PMC104275 DOI: 10.1128/jvi.73.9.7489-7496.1999] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We recently reported that a cationic peptide, T22 ([Tyr(5,12), Lys(7)]-polyphemusin II), specifically inhibits human immunodeficiency virus type 1 (HIV-1) infection mediated by CXCR4 (T. Murakami et al., J. Exp. Med. 186:1389-1393, 1997). Here we demonstrate that T22 effectively inhibits replication of T-tropic HIV-1, including primary isolates, but not of non-T-tropic strains. By using a panel of chimeric viruses between T- and M-tropic HIV-1 strains, viral determinants for T22 susceptibility were mapped to the V3 loop region of gp120. T22 bound to CXCR4 and interfered with stromal-cell-derived factor-1alpha-CXCR4 interactions in a competitive manner. Blocking of anti-CXCR4 monoclonal antibodies by T22 suggested that the peptide interacts with the N terminus and two of the extracellular loops of CXCR4. Furthermore, the inhibition of cell-cell fusion in cells expressing CXCR4/CXCR2 chimeric receptors suggested that determinants for sensitivity of CXCR4 to T22 include the three extracellular loops of the coreceptor.
Collapse
Affiliation(s)
- T Murakami
- Department of Microbiology and Molecular Virology, Faculty of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8519, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
|
24
|
Xu Y, Tamamura H, Arakaki R, Nakashima H, Zhang X, Fujii N, Uchiyama T, Hattori T. Marked increase in anti-HIV activity, as well as inhibitory activity against HIV entry mediated by CXCR4, linked to enhancement of the binding ability of tachyplesin analogs to CXCR4. AIDS Res Hum Retroviruses 1999; 15:419-27. [PMID: 10195751 DOI: 10.1089/088922299311169] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
T22 ([Tyr5,12, Lys7]-polyphemusin II) is a strong anti-HIV compound. Six analogs of T22 and two natural forms were synthesized. Of them, all downsized peptides (14 residues; TW70, T131, T134, and T140) showed a higher selectivity index than did other, 17- or 18-residue peptides. In particular, T134 and T140 showed both lower cytotoxicity and higher antiviral activity than did T22 against HIV infection of MT-4 cells, an HTLV-I-bearing T cell line. To clarify the inhibitory mode of T22 and its analogs, we used a single-round replication assay (luciferase assay), in which different envelope-bearing pseudotypes were used to infect CXCR4- or CCR5-bearing U87 cells via CD4. All of the analogs inhibited T cell line-tropic strain HXB-2 (X4) and dual-tropic strain 89.6 (R5X4) HIV infections mediated by CXCR4, but had no effect on macrophage-tropic strain ADA (R5) or 89.6 HIV infections mediated by CCR5. The inhibition by T134 (IC50 of 2.70 nM) and T140 (IC50 of 0.432 nM) was also stronger than that by T22 (IC50 of 5.05 nM). The binding of anti-CXCR4 monoclonal antibody 12G5 to lymphoma-derived T cell line Sup-T1 was more efficiently blocked by T134 and T140 than by T22. Taken together, T22 and its analogs T134 and T140 exerted their inhibition by specific binding to CXCR4. The marked increase in the anti-HIV activity of T134 and T140 was ascribed to an enhancement in their ability to bind to CXCR4.
Collapse
Affiliation(s)
- Y Xu
- Laboratory of Virus Immunology, Research Center for Acquired Immunodeficiency Syndrome, Institute for Virus Research, Kyoto University, Japan
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Arakaki R, Tamamura H, Premanathan M, Kanbara K, Ramanan S, Mochizuki K, Baba M, Fujii N, Nakashima H. T134, a small-molecule CXCR4 inhibitor, has no cross-drug resistance with AMD3100, a CXCR4 antagonist with a different structure. J Virol 1999; 73:1719-23. [PMID: 9882387 PMCID: PMC104006 DOI: 10.1128/jvi.73.2.1719-1723.1999] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
T22, an analog of polyphemusin II (18 amino acid residues), was found to block T-tropic human immunodeficiency virus type 1 (HIV-1) entry into target cells as a CXCR4 inhibitor. We synthesized T134, a small analog (14 amino acid residues) of T22 with reduced positive charges. T134 exhibited highly potent activity and significantly less cytotoxicity in comparison to that of T22. T134 prevents the anti-CXCR4 monoclonal antibody from binding to peripheral blood mononuclear cells but has no effect on the binding of anti-CCR5 monoclonal antibodies. Since T134 inhibits the binding of stromal cell-derived factor-1 (SDF-1) to MT-4 cells, it seems that T134 prevents HIV-1 entry by binding to CXCR4. The bicyclam AMD3100 has also been shown to block HIV-1 entry via CXCR4 but not via CCR5. Both T134 and AMD3100 are CXCR4 antagonists and low-molecular-weight compounds but have different structures. Our results indicate that T134 is active against wild-type T-tropic HIV-1 strains and against AMD3100-resistant strains.
Collapse
Affiliation(s)
- R Arakaki
- Department of Microbiology and Immunology, Kagoshima University Dental School, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
Chemokines mediate their effects by binding to cell-surface receptors that belong to the seven-transmembrane-domain superfamily of proteins. Chemokine receptors have been subject to intense scrutiny following the recent discovery that several of them are co-receptors for HIV-1. Here, Richard Horuk reviews the latest developments in chemokine receptor research with a particular focus on their role as HIV-1 co-receptors.
Collapse
MESH Headings
- Amino Acid Sequence
- Amino Acid Substitution
- Animals
- CD4 Antigens/genetics
- CD4 Antigens/physiology
- CD4-Positive T-Lymphocytes/virology
- Chemokines/physiology
- Disease Progression
- Gene Expression Regulation
- HIV Envelope Protein gp120/metabolism
- HIV Infections/metabolism
- HIV Infections/therapy
- HIV Infections/virology
- HIV-1/classification
- HIV-1/physiology
- Macaca mulatta
- Macromolecular Substances
- Macrophages/virology
- Molecular Sequence Data
- Rabies virus
- Receptors, CCR2
- Receptors, CCR5/chemistry
- Receptors, CCR5/genetics
- Receptors, CCR5/physiology
- Receptors, CXCR4/chemistry
- Receptors, CXCR4/genetics
- Receptors, CXCR4/physiology
- Receptors, Chemokine/chemistry
- Receptors, Chemokine/genetics
- Receptors, Chemokine/physiology
- Receptors, Cytokine/chemistry
- Receptors, Cytokine/genetics
- Receptors, Cytokine/physiology
- Recombinant Fusion Proteins/metabolism
- Structure-Activity Relationship
- Vesicular stomatitis Indiana virus
Collapse
Affiliation(s)
- R Horuk
- Dept of Immunology, Berlex Biosciences, Richmond, CA 94804, USA
| |
Collapse
|
27
|
Tamamura H, Imai M, Ishihara T, Masuda M, Funakoshi H, Oyake H, Murakami T, Arakaki R, Nakashima H, Otaka A, Ibuka T, Waki M, Matsumoto A, Yamamoto N, Fujii N. Pharmacophore identification of a chemokine receptor (CXCR4) antagonist, T22 ([Tyr(5,12),Lys7]-polyphemusin II), which specifically blocks T cell-line-tropic HIV-1 infection. Bioorg Med Chem 1998; 6:1033-41. [PMID: 9730240 DOI: 10.1016/s0968-0896(98)00061-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We have previously found that T22 ([Tyr(5,12), Lys7]-polyphemusin II) has strong anti-human immunodeficiency virus (HIV) activity, and that T22 inhibits T cell-line-tropic HIV-1 infection mediated by CXCR4/fusin. T22 is an 18-residue peptide amide, which takes an antiparallel beta-sheet structure that is maintained by two disulfide bridges. Structure-activity relationship (SAR) studies on T22 have disclosed the contributions of each region of T22 to activity or cytotoxicity, and have provided the following useful information to develop new CXCR4 antagonists: The number of Arg residues in the N-terminal and C-terminal regions of T22 is closely related to anti-HIV activity. Addition of a variety of functional groups at the N-terminal end results in increases in activity. Disulfide rings, especially the major disulfide loop, are indispensable for anti-HIV activity and maintenance of the beta-sheet structure. Trp3 can be replaced by other aromatic residues (Tyr, Phe and L-2-naphthylalanine). Between two repeats of Tyr-Arg-Lys, which are a characteristic structure in T22, Tyr-Arg-Lys in the N-terminal portion is more closely associated with anti-HIV activity and maintenance of the beta-sheet structure. A positive charge in the side chain at the (i + 1) position of the beta-turn region is necessary for strong activity. Through these studies, we have found several compounds having higher selectivity indexes (50% cytotoxic concentration/50% effective concentration) than that of T22.
Collapse
Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Tamamura H, Waki M, Imai M, Otaka A, Ibuka T, Waki K, Miyamoto K, Matsumoto A, Murakami T, Nakashima H, Yamamoto N, Fujii N. Downsizing of an HIV-cell fusion inhibitor, T22 ([Tyr5,12, Lys7]-polyphemusin II), with the maintenance of anti-HIV activity and solution structure. Bioorg Med Chem 1998; 6:473-9. [PMID: 9597190 DOI: 10.1016/s0968-0896(97)10055-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
T22 ([Tyr5,12,Lys7]-polyphemusin II) has been shown to have strong anti-human immunodeficiency virus (HIV) activity comparable to that of 3'-azido-2',3'-dideoxythymidine (AZT). T22, an 18-residue peptide amide, takes an antiparallel beta-sheet structure that is maintained by two disulfide bridges. Herein we synthesized several shortened analogs of T22 in order to search for a more suitable lead compound. A 14-residue analog having one disulfide bridge, TW70 (des-[Cys8,13, Tyr9,12]-[D-Lys10, Pro11]-T22), was found to have highly potent activity comparable to that of T22, and to take an antiparallel beta-sheet structure similar to that of T22. This indicates that the molecular size of T22 can be reduced without loss of activity or significant change in the secondary structure, and that TW70 may represent a novel lead compound. Furthermore, modifying the N-terminal alpha-amino group of TW70 with a fluoresceinthiocarbamoyl group, and the epsilon-amino group of D-Lys8 at the turn portion with a 5-aminopentanoyl group remarkably increased the selectivity index (50% cytotoxic concentration/50% effective concentration).
Collapse
Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan. or
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Tamamura H, Arakaki R, Funakoshi H, Imai M, Otaka A, Ibuka T, Nakashima H, Murakami T, Waki M, Matsumoto A, Yamamoto N, Fujii N. Effective lowly cytotoxic analogs of an HIV-cell fusion inhibitor, T22 ([Tyr5,12, Lys7]-polyphemusin II). Bioorg Med Chem 1998; 6:231-8. [PMID: 9547946 DOI: 10.1016/s0968-0896(97)10037-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A tachyplesin peptide analog, T22 ([Tyr5,12, Lys7]-polyphemusin II), and its shortened congener, TW70 (des-[Cys8,13, Tyr9,12]-[D-Lys10, Pro11]-T22) have strong anti-human immunodeficiency virus (HIV) activity, comparable to that of 3'-azido-2', 3'-dideoxythymidine (AZT). T22 and TW70 are extremely basic peptides, containing 5 Arg residues and 3 Lys residues. The number of positive charges might be related in part to high collateral cytotoxicities of T22 and TW70. Here we have synthesized several analogs, in which the number of positive charges has been reduced through amino acid substitutions using Glu or L-citrulline. As a result, several effective compounds have been found which possess higher selectivity indexes (SIs, 50% cytotoxic concentration/50% effective concentration) than those of T22 and TW70. Higher SIs were attributed mainly to a decrease in cytotoxicity.
Collapse
Affiliation(s)
- H Tamamura
- Graduate School of Pharmaceutical Sciences, Kyoto University, Japan. /
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Murakami T, Nakajima T, Koyanagi Y, Tachibana K, Fujii N, Tamamura H, Yoshida N, Waki M, Matsumoto A, Yoshie O, Kishimoto T, Yamamoto N, Nagasawa T. A small molecule CXCR4 inhibitor that blocks T cell line-tropic HIV-1 infection. J Exp Med 1997; 186:1389-93. [PMID: 9334379 PMCID: PMC2199089 DOI: 10.1084/jem.186.8.1389] [Citation(s) in RCA: 302] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Several members of the chemokine receptor family have been shown to function in association with CD4 to permit human immunodeficiency virus type 1 (HIV-1) entry and infection. The CXC chemokine receptor CXCR4/fusin is a receptor for pre-B cell growth stimulating factor (PBSF)/stromal cell-derived factor 1 (SDF-1) and serves as a coreceptor for the entry of T cell line-tropic HIV-1 strains. Thus, the development of CXCR4 antagonists or agonists may be useful in the treatment of HIV-1 infection. T22 ([Tyr5,12,Lys7]-polyphemusin II) is a synthesized peptide that consists of 18 amino acid residues and an analogue of polyphemusin II isolated from the hemocyte debris of American horseshoe crabs (Limulus polyphemus). T22 was found to specifically inhibit the ability of T cell line-tropic HIV-1 to induce cell fusion and infect the cell lines transfected with CXCR4 and CD4 or peripheral blood mononuclear cells. In addition, T22 inhibited Ca2+ mobilization induced by pre-B cell growth stimulating factor (PBSF)/SDF-1 stimulation through CXCR4. Thus, T22 is a small molecule CXCR4 inhibitor that blocks T cell line-tropic HIV-1 entry into target cells.
Collapse
Affiliation(s)
- T Murakami
- Department of Microbiology, Tokyo Medical and Dental University School of Medicine, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Tamamura H, Ishihara T, Otaka A, Murakami T, Ibuka T, Waki M, Matsumoto A, Yamamoto N, Fujii N. Analysis of the interaction of an anti-HIV peptide, T22 ([Tyr5, 12, Lys7]-polyphemusin II), with gp120 and CD4 by surface plasmon resonance. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1298:37-44. [PMID: 8948487 DOI: 10.1016/s0167-4838(96)00113-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have previously found that T22 ([Tyr5, 12, Lys7]-polyphemusin II) exhibits strong anti-human immunodeficiency virus (HIV) activity comparable to that of 3'-azido-2', 3'-dideoxythymidine (AZT). The inhibition mechanism of T22 on HIV-replication has not been elucidated precisely yet, and hence the target molecules of T22 have not been identified. However, our recent research suggested that T22 exerts its effect by blocking virus-cell fusion at an early stage of HIV infection and that T22 might interact with an HIV envelope protein and/or a T-cell surface protein, both of which are critical for HIV infection. In this paper we demonstrated that T22 binds specifically to both gp120 (an envelope protein of HIV) and CD4 (a T-cell surface protein) and that both bindings can be inhibited by an anti-T22 antibody, using biosensor technology (BIAcoreTM) based on the principles of surface plasmon resonance. Linearization by the BIAcoreTM system (BIAlogue software) and nonlinear least squares analysis by curve fitting with exponential equations showed that both interactions have close dissociation constants (approximately 10(-7) M). The present study suggests that T22 inhibits the virus-cell fusion process through binding to both gp120 and CD4.
Collapse
Affiliation(s)
- H Tamamura
- Faculty of Pharmaceutical Sciences, Kyoto University, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Waki M, Waki K, Miyamoto K, Matsumoto A, Tamamura H, Fujii N, Murakami T, Nakashima H, Yamamoto N. Molecular Size of an Anti-HIV Peptide, T22, Can Be Reduced without Loss of the Activity. CHEM LETT 1996. [DOI: 10.1246/cl.1996.571] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|