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Lai X, Tang J, ElSayed MEH. Recent advances in proteolytic stability for peptide, protein, and antibody drug discovery. Expert Opin Drug Discov 2021; 16:1467-1482. [PMID: 34187273 DOI: 10.1080/17460441.2021.1942837] [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] [Indexed: 10/21/2022]
Abstract
Introduction: To discover and develop a peptide, protein, or antibody into a drug requires overcoming multiple challenges to obtain desired properties. Proteolytic stability is one of the challenges and deserves a focused investigation.Areas covered: This review concentrates on improving proteolytic stability by engineering the amino acids around the cleavage sites of a liable peptide, protein, or antibody. Peptidases are discussed on three levels including all peptidases in databases, mixtures based on organ and tissue types, and individual peptidases. The technique to identify cleavage sites is spotlighted on mass spectrometry-based approaches such as MALDI-TOF and LC-MS. For sequence engineering, the replacements that have been commonly applied with a higher chance of success are highlighted at the beginning, while the rarely used and more complicated replacements are discussed later. Although a one-size-fits-all approach does not exist to apply to different projects, this review provides a 3-step strategy for effectively and efficiently conducting the proteolytic stability experiments to achieve the eventual goal of improving the stability by engineering the molecule itself.Expert opinion: Improving the proteolytic stability is a spiraling up process sequenced by testing and engineering. There are many ways to engineer amino acids, but the choice must consider the cost and properties affected by the changes of the amino acids.
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Affiliation(s)
- Xianyin Lai
- Biotechnology Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA
| | - Jason Tang
- Biotechnology Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA
| | - Mohamed E H ElSayed
- Biotechnology Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA
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Desale K, Kuche K, Jain S. Cell-penetrating peptides (CPPs): an overview of applications for improving the potential of nanotherapeutics. Biomater Sci 2021; 9:1153-1188. [PMID: 33355322 DOI: 10.1039/d0bm01755h] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In the field of nanotherapeutics, gaining cellular entry into the cytoplasm of the target cell continues to be an ultimate challenge. There are many physicochemical factors such as charge, size and molecular weight of the molecules and delivery vehicles, which restrict their cellular entry. Hence, to dodge such situations, a class of short peptides called cell-penetrating peptides (CPPs) was brought into use. CPPs can effectively interact with the cell membrane and can assist in achieving the desired intracellular entry. Such strategy is majorly employed in the field of cancer therapy and diagnosis, but now it is also used for other purposes such as evaluation of atherosclerotic plaques, determination of thrombin levels and HIV therapy. Thus, the current review expounds on each of these mentioned aspects. Further, the review briefly summarizes the basic know-how of CPPs, their utility as therapeutic molecules, their use in cancer therapy, tumor imaging and their assistance to nanocarriers in improving their membrane penetrability. The review also discusses the challenges faced with CPPs pertaining to their stability and also mentions the strategies to overcome them. Thus, in a nutshell, this review will assist in understanding how CPPs can present novel possibilities for resolving the conventional issues faced with the present-day nanotherapeutics.
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Affiliation(s)
- Kalyani Desale
- Centre for Pharmaceutical Nanotechnology, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab-160062, India.
| | - Kaushik Kuche
- Centre for Pharmaceutical Nanotechnology, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab-160062, India.
| | - Sanyog Jain
- Centre for Pharmaceutical Nanotechnology, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab-160062, India.
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Soleymani-Goloujeh M, Nokhodchi A, Niazi M, Najafi-Hajivar S, Shahbazi-Mojarrad J, Zarghami N, Zakeri-Milani P, Mohammadi A, Karimi M, Valizadeh H. Effects of N-terminal and C-terminal modification on cytotoxicity and cellular uptake of amphiphilic cell penetrating peptides. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2017; 46:91-103. [DOI: 10.1080/21691401.2017.1414823] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Mehdi Soleymani-Goloujeh
- Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Ali Nokhodchi
- Pharmaceutics Research Laboratory, School of Life Sciences, University of Sussex, Falmer, Brighton, UK
| | - Mehri Niazi
- Student Research Committee, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeedeh Najafi-Hajivar
- Student Research Committee, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javid Shahbazi-Mojarrad
- Biotechnology Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nosratollah Zarghami
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Parvin Zakeri-Milani
- Liver and Gastrointestinal Diseases Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Mohammadi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Karimi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hadi Valizadeh
- Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
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Kristensen M, Birch D, Mørck Nielsen H. Applications and Challenges for Use of Cell-Penetrating Peptides as Delivery Vectors for Peptide and Protein Cargos. Int J Mol Sci 2016; 17:E185. [PMID: 26840305 PMCID: PMC4783919 DOI: 10.3390/ijms17020185] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 01/04/2016] [Accepted: 01/07/2016] [Indexed: 01/21/2023] Open
Abstract
The hydrophilic nature of peptides and proteins renders them impermeable to cell membranes. Thus, in order to successfully deliver peptide and protein-based therapeutics across the plasma membrane or epithelial and endothelial barriers, a permeation enhancing strategy must be employed. Cell-penetrating peptides (CPPs) constitute a promising tool and have shown applications for peptide and protein delivery into cells as well as across various epithelia and the blood-brain barrier (BBB). CPP-mediated delivery of peptides and proteins may be pursued via covalent conjugation of the CPP to the cargo peptide or protein or via physical complexation obtained by simple bulk-mixing of the CPP with its cargo. Both approaches have their pros and cons, and which is the better choice likely relates to the physicochemical properties of the CPP and its cargo as well as the route of administration, the specific barrier and the target cell. Besides the physical barrier, a metabolic barrier must be taken into consideration when applying peptide-based delivery vectors, such as the CPPs, and stability-enhancing strategies are commonly employed to prolong the CPP half-life. The mechanisms by which CPPs translocate cell membranes are believed to involve both endocytosis and direct translocation, but are still widely investigated and discussed. The fact that multiple factors influence the mechanisms responsible for cellular CPP internalization and the lack of sensitive methods for detection of the CPP, and in some cases the cargo, further complicates the design and conduction of conclusive mechanistic studies.
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Affiliation(s)
- Mie Kristensen
- Section for Biologics, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| | - Ditlev Birch
- Section for Biologics, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
| | - Hanne Mørck Nielsen
- Section for Biologics, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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Abstract
In the era of biomedicines and engineered carrier systems, cell penetrating peptides (CPPs) have been established as a promising tool for therapeutic application. Likewise, other therapeutic peptides, successful in vivo application of CPPs will strongly depend on peptide stability, the bottleneck for this type of biodegradable molecules. In this review, the authors describe the current knowledge of the in vivo degradation for known CPPs and the different strategies available to provide a higher resistance to metabolic degradation while preserving cell penetration efficiency. Peptide stability can be improved by different means, either modifying the structure to make it unrecognizable to proteases, or preventing access of proteolytic enzymes by applying conformation restriction or shielding strategies.
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Haghi M, Ong HX, Traini D, Young P. Across the pulmonary epithelial barrier: Integration of physicochemical properties and human cell models to study pulmonary drug formulations. Pharmacol Ther 2014; 144:235-52. [DOI: 10.1016/j.pharmthera.2014.05.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 04/30/2014] [Indexed: 11/16/2022]
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Reissmann S. Cell penetration: scope and limitations by the application of cell-penetrating peptides. J Pept Sci 2014; 20:760-84. [DOI: 10.1002/psc.2672] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 06/06/2014] [Accepted: 06/10/2014] [Indexed: 12/23/2022]
Affiliation(s)
- Siegmund Reissmann
- Friedrich Schiller University, Biological and Pharmaceutical Faculty; Institute of Biochemistry and Biophysics; Dornburger Strasse 25 07743 Jena Germany
- Jena Bioscience GmbH; Loebstedter Strasse 80 07749 Jena Germany
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Apte A, Koren E, Koshkaryev A, Torchilin VP. Doxorubicin in TAT peptide-modified multifunctional immunoliposomes demonstrates increased activity against both drug-sensitive and drug-resistant ovarian cancer models. Cancer Biol Ther 2013; 15:69-80. [PMID: 24145298 DOI: 10.4161/cbt.26609] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Multidrug resistance (MDR) is a hallmark of cancer cells and a crucial factor in chemotherapy failure, cancer reappearance, and patient deterioration. We have previously described the physicochemical characteristics and the in vitro anticancer properties of a multifunctional doxorubicin-loaded liposomal formulation. Lipodox(®), a commercially available PEGylated liposomal doxorubicin, was made multifunctional by surface-decorating with a cell-penetrating peptide, TATp, conjugated to PEG 1000-PE, to enhance liposomal cell uptake. A pH-sensitive polymer, PEG 2000-Hz-PE, with a pH-sensitive hydrazone (Hz) bond to shield the peptide in the body and expose it only at the acidic tumor cell surface, was used as well. In addition, an anti-nucleosome monoclonal antibody 2C5 attached to a long-chain polymer to target nucleosomes overexpressed on the tumor cell surface was also present. Here, we report the in vitro cell uptake and cytotoxicity of the modified multifunctional immunoliposomes as well as the in vivo studies on tumor xenografts developed subcutaneously in nude mice with MDR and drug-sensitive human ovarian cancer cells (SKOV-3). Our results show the ability of multifunctional immunoliposomes to overcome MDR by enhancing cytotoxicity in drug-resistant cells, compared with non-modified liposomes. Furthermore, in comparison with the non-modified liposomes, upon intravenous injection of these multifunctional immunoliposomes into mice with tumor xenografts, a significant reduction in tumor growth and enhanced therapeutic efficacy of the drug in both drug-resistant and drug-sensitive mice was obtained. The use of "smart" multifunctional delivery systems may provide the basis for an effective strategy to develop, improve, and overcome MDR cancers in the future.
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Affiliation(s)
- Anjali Apte
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
| | - Erez Koren
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
| | - Alexander Koshkaryev
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
| | - Vladimir P Torchilin
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
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Soudy R, Chen C, Kaur K. Novel peptide-doxorubucin conjugates for targeting breast cancer cells including the multidrug resistant cells. J Med Chem 2013; 56:7564-73. [PMID: 24028446 DOI: 10.1021/jm400647r] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The efficacy of chemotherapeutic doxorubucin (Dox) in cancer treatment is limited by two main factors, nonspecific toxicity and the emergence of tumor resistance. To overcome these hurdles, in this study peptide-Dox conjugates were prepared. A decapeptide 18-4a (NH₂-WxEAAYQkFL-CONH₂) [corrected] with high specificity for breast cancer cells and improved proteolytic stability was conjugated to Dox to give peptide-Dox ester (1) and amide (2) conjugates. Cell uptake studies showed that the conjugates were 6-10 times selective for breast cancerous cells (MCF-7 and MDA-MB-435) over noncancerous cells (HUVECs and MCF-10A). Conjugate 1 displayed similar toxicity as free Dox toward the breast cancerous cells and was about 40 times less toxic toward the noncancerous cells and 4-fold more toxic toward the Dox resistant MDA-MB-435-MDR cells than the free Dox. These data suggest that conjugate 1 can be used as a potential prodrug for improving the therapeutic index of Dox and potentially many other cytotoxic drugs.
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Affiliation(s)
- Rania Soudy
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta , Edmonton, Alberta, T6G 2E1, Canada
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Verdurmen WPR, Wallbrecher R, Schmidt S, Eilander J, Bovee-Geurts P, Fanghänel S, Bürck J, Wadhwani P, Ulrich AS, Brock R. Cell surface clustering of heparan sulfate proteoglycans by amphipathic cell-penetrating peptides does not contribute to uptake. J Control Release 2013; 170:83-91. [PMID: 23669260 DOI: 10.1016/j.jconrel.2013.05.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 04/27/2013] [Accepted: 05/02/2013] [Indexed: 10/26/2022]
Abstract
For arginine-rich cell-penetrating peptides (CPPs), an association with heparan sulfate (HS) chains is considered the first step in the stimulation of uptake for many cells. Much less is known about the role of HS chains in the cell-association and internalization of arginine-free amphipathic CPP such as transportan-10 (TP10). Here, we report that various TP10 analogs differ in their capacity to accumulate on HS-rich plasma membranes in an HS-dependent manner. No accumulation was observed on HS-poor plasma membranes or when HS was removed by enzymatic cleavage. The TP10 analog that strongly clustered on the cell surface, also showed a pronounced capacity to form clusters with HS chains in solution. However, aggregation occurred in a thermodynamically different way compared to the interaction of arginine-rich CPP with HS. To monitor the impact of the peptide on the aggregation of the glycocalyx by time-lapse microscopy, sialic acids were visualized by metabolic labeling using copper-free click chemistry to attach fluorophores to metabolically incorporated azido sugars. Strikingly, a highly enhanced HS-mediated accumulation on the plasma membrane of a particular TP10 analog did not correlate with a better uptake. These findings illustrate that the mode of interaction between cell-penetrating peptides and HS chains has important functional consequences regarding peptide internalization and that there is no direct coupling of interaction, accumulation and uptake.
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Affiliation(s)
- Wouter P R Verdurmen
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Post 286, PO Box 9101, 6500 HB Nijmegen, The Netherlands
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Infection by CXCR4-Tropic Human Immunodeficiency Virus Type 1 Is Inhibited by the Cationic Cell-Penetrating Peptide Derived from HIV-1 Tat. INTERNATIONAL JOURNAL OF PEPTIDES 2012; 2012:349427. [PMID: 22319541 PMCID: PMC3272803 DOI: 10.1155/2012/349427] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 10/15/2011] [Accepted: 10/25/2011] [Indexed: 01/29/2023]
Abstract
Cell-penetrating peptides (CPP), which are short peptides that are capable of crossing the plasma membrane of a living cell, are under development as delivery vehicles for therapeutic agents that cannot themselves enter the cell. One well-studied CPP is the 10-amino acid peptide derived from the human immunodeficiency virus type 1 (HIV-1) Tat protein. In experiments to test the hypothesis that multiple cationic amino acids within Tat peptide confer antiviral activity against HIV-1, introduction of Tat peptide resulted in concentration-dependent inhibition of HIV-1 IIIB infection. Using Tat peptide variants containing arginine substitutions for two nonionic residues and two lysine residues, HIV-1 inhibition experiments demonstrated a direct relationship between cationic charge and antiviral potency. These studies of Tat peptide as an antiviral agent raise new questions about the role of Tat in HIV-1 replication and provide a starting point for the development of CPPs as novel HIV-1 inhibitors.
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Lee JS, Tung CH. Enhanced cellular uptake and metabolic stability of lipo-oligoarginine peptides. Biopolymers 2011; 96:772-9. [PMID: 22252426 DOI: 10.1002/bip.21681] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 04/06/2011] [Accepted: 05/10/2011] [Indexed: 12/22/2022]
Abstract
Developing efficient cellular delivery vectors is crucial for designing novel therapeutic agents to enhance their plasma membrane permeability and metabolic stability in cells. Previously, we engineered cell penetrating peptide vectors named as "lipo-oligoarginine peptides" (LOAPs) by conjugating a proper combination of fatty acid and oligoarginine that translocated into cell easily without adverse effect on cell viability. In the present study, we report a systemic evaluation of cellular uptake and metabolic stability of LOAPs in Jurkat cells by introducing different combination of D-Arg residues in the peptide backbone. The cellular uptake and intracellular fate, cell viability, and metabolic stability and proteolytic degradation patterns of various LOAPs consisted of different combination of L- and D-Arg sequences were confirmed by flow cytometry, cytotoxicity assay, and analytical RP-HPLC with MALDI-TOF mass. All investigated LOAPs penetrated the cell efficiently with low cellular toxicity. The LOAPs having D-Arg residues at their N-termini seemed to have better metabolic stability than the LOAPs having C-terminal D-Arg residues. The metabolic degradation patterns were similar among all investigated LOAPs. The major hydrolytic site was between lauroyl group and β-Ala residue. Without the lipid chain, the oligoarginine peptide was pumped out ofcells easily. The results presented in this study suggest that structurally modified LOAPs could be used as a novel CPP design toward improved therapeutic application.
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Affiliation(s)
- Jae Sam Lee
- Department of Radiology, The Methodist Hospital Research Institute, Weill Cornell Medical College, Houston, TX 77030, USA
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Koren E, Apte A, Sawant RR, Grunwald J, Torchilin VP. Cell-penetrating TAT peptide in drug delivery systems: proteolytic stability requirements. Drug Deliv 2011; 18:377-84. [PMID: 21438724 DOI: 10.3109/10717544.2011.567310] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The stability and activity of the HIV cell-penetrating TAT peptide (TATp) on the surface of TATp-modified micelles and liposomes in relation to its proteolytic cleavage was investigated. TATp moieties were attached to the surface of these nanocarriers using TATp modified with a conjugate of phosphatidyl ethanolamine with a 'short' PEG (PEG-PE). Following pre-incubation with trypsin, elastase, or collagenase, the proteolytic stability of TATp on the surface of these modified carriers was studied by HPLC with fluorescence detection using fluorenylmethyl chloroformate (FMOC) labeling. All tested enzymes produced a dose-dependent cleavage of TATp as shown by the presence of TATp Arg-Arg fragments. Inhibition of TATp cleavage occurred when these TATp-micelles were modified by the addition of longer PEG-PE blocks, indicating an effective shielding of TATp from proteolysis by these blocks. TATp-modified carriers were also tested for their ability to accumulate in EL-4, HeLa, and B16-F10 cells. Trypsin treatment of TATp-modified liposomes and micelles resulted in decreased uptake and cell interaction, as measured by fluorescence microscopy and fluorescence-activated cell sorting techniques. Furthermore, a decrease in the cytotoxicity of TATp-modified liposomes loaded with doxorubicin (Doxil) was observed following trypsin treatment. In conclusion, steric shielding of TATp is essential to ensure its in vivo therapeutic function.
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Affiliation(s)
- Erez Koren
- Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, Massachusetts 02115, USA.
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Kilk K, Mahlapuu R, Soomets U, Langel Ü. Analysis of in vitro toxicity of five cell-penetrating peptides by metabolic profiling. Toxicology 2009; 265:87-95. [DOI: 10.1016/j.tox.2009.09.016] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Revised: 09/21/2009] [Accepted: 09/22/2009] [Indexed: 01/27/2023]
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Subcellular neuropharmacology: the importance of intracellular targeting. Trends Pharmacol Sci 2009; 30:203-11. [DOI: 10.1016/j.tips.2009.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Revised: 01/09/2009] [Accepted: 01/21/2009] [Indexed: 01/03/2023]
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