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Liu C, Jiang K, Tai L, Liu Y, Wei G, Lu W, Pan W. Facile Noninvasive Retinal Gene Delivery Enabled by Penetratin. ACS APPLIED MATERIALS & INTERFACES 2016; 8:19256-67. [PMID: 27400087 DOI: 10.1021/acsami.6b04551] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Gene delivery to the posterior segment of the eye is severely hindered by the impermeability of defensive barriers; therefore, in clinical settings, genomic medicines are mainly administered by intravitreal injection. We previously found that penetratin could transport the covalently conjugated fluorophore to the fundus oculi by topical instillation. In this study, gene delivery systems enabled by penetratin were designed based on electrostatic binding to target the retina via a noninvasive administration route and prepared with red fluorescent protein plasmid (pRFP) and/or poly(amidoamine) dendrimer of low molecular weight (G3 PAMAM). Formulation optimization, structure confirmation, and characterization were subsequently conducted. Penetratin alone showed limited ability to condense the plasmid but had powerful uptake and transfection by corneal and conjunctival cells. G3 PAMAM was nontoxic to the ocular cells, and when introduced into the penetratin-incorporated complex, the plasmid was condensed more compactly. Therefore, further improved cellular uptake and transfection were observed. After being instilled in the conjunctival sac of rats, the intact complexes penetrated rapidly from the ocular surface into the fundus and resided in the retina for more than 8 h, which resulted in efficient expression of RFP in the posterior segment. Intraocular distribution of the complexes suggested that the plasmids were absorbed into the eyes through a noncorneal pathway during which penetratin played a crucial role. This study provides a facile and friendly approach for intraocular gene delivery and is an important step toward the development of noninvasive gene therapy for posterior segment diseases.
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Afsari HS, Cardoso Dos Santos M, Lindén S, Chen T, Qiu X, van Bergen en Henegouwen PMP, Jennings TL, Susumu K, Medintz IL, Hildebrandt N, Miller LW. Time-gated FRET nanoassemblies for rapid and sensitive intra- and extracellular fluorescence imaging. SCIENCE ADVANCES 2016; 2:e1600265. [PMID: 27386579 PMCID: PMC4928903 DOI: 10.1126/sciadv.1600265] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 05/19/2016] [Indexed: 05/20/2023]
Abstract
Time-gated Förster resonance energy transfer (FRET) using the unique material combination of long-lifetime terbium complexes (Tb) and semiconductor quantum dots (QDs) provides many advantages for highly sensitive and multiplexed biosensing. Although time-gated detection can efficiently suppress sample autofluorescence and background fluorescence from directly excited FRET acceptors, Tb-to-QD FRET has rarely been exploited for biomolecular imaging. We demonstrate Tb-to-QD time-gated FRET nanoassemblies that can be applied for intra- and extracellular imaging. Immunostaining of different epitopes of the epidermal growth factor receptor (EGFR) with Tb- and QD-conjugated antibodies and nanobodies allowed for efficient Tb-to-QD FRET on A431 cell membranes. The broad usability of Tb-to-QD FRET was further demonstrated by intracellular Tb-to-QD FRET and Tb-to-QD-to-dye FRET using microinjection as well as cell-penetrating peptide-mediated endocytosis with HeLa cells. Effective brightness enhancement by FRET from several Tb to the same QD, the use of low nanomolar concentrations, and the quick and sensitive detection void of FRET acceptor background fluorescence are important advantages for advanced intra- and extracellular imaging of biomolecular interactions.
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OROSCO RYANK, SAVARIAR ELAMPRAKASHN, WEISSBROD PHILIPA, DIAZ-PEREZ JULIOA, BOUVET MICHAEL, TSIEN ROGERY, NGUYEN QUYENT. Molecular targeting of papillary thyroid carcinoma with fluorescently labeled ratiometric activatable cell penetrating peptides in a transgenic murine model. J Surg Oncol 2016; 113:138-43. [PMID: 26799257 PMCID: PMC4986916 DOI: 10.1002/jso.24129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 11/28/2015] [Indexed: 01/18/2023]
Abstract
BACKGROUND AND OBJECTIVES Molecularly targeted fluorescent molecules may help detect tumors that are unseen by traditional white-light surgical techniques. We sought to evaluate a fluorescent ratiometric activatable cell penetrating peptide (RACPP) for tumor detection in a transgenic model of PTC. METHODS Thirteen BRAFV600E mice with PTC were studied-seven injected intravenously with RACPP, four controls with saline. Total thyroidectomy was performed with microscopic white-light visualization. Fluorescent imaging of post-thyroidectomy fields was performed, and tissue with increased signal was removed and evaluated for PTC. Final samples were analyzed by a pathologist blinded to conditions. Vocal cord function was evaluated postoperatively with video laryngoscopy. RESULTS The average in situ ratiometric (Cy5/Cy7) thyroid tumor-to-background contrast ratio was 2.27 +/- 0.91. Fluorescence-guided clean-up following thyroidectomy identified additional tumor in 2 of 7 RACPP animals (smallest dimension 1.2 mm), and decreased the number of animals with residual tumor from 4 to 3. All retained tumor foci on final pathology were smaller than 0.76 mm. Intact vocal abduction was present in all of the RACPP animals. CONCLUSIONS RACPPs successfully targeted PTC in a transgenic thyroidectomy model, and allowed for residual tumor detection that reduced positive margins beyond what was possible with white-light surgery alone.
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Ndeboko B, Lemamy GJ, Nielsen PE, Cova L. Therapeutic Potential of Cell Penetrating Peptides (CPPs) and Cationic Polymers for Chronic Hepatitis B. Int J Mol Sci 2015; 16:28230-41. [PMID: 26633356 PMCID: PMC4691041 DOI: 10.3390/ijms161226094] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/17/2015] [Accepted: 11/20/2015] [Indexed: 02/06/2023] Open
Abstract
Chronic hepatitis B virus (HBV) infection remains a major health problem worldwide. Because current anti-HBV treatments are only virostatic, there is an urgent need for development of alternative antiviral approaches. In this context, cell-penetrating peptides (CPPs) and cationic polymers, such as chitosan (CS), appear of particular interest as nonviral vectors due to their capacity to facilitate cellular delivery of bioactive cargoes including peptide nucleic acids (PNAs) or DNA vaccines. We have investigated the ability of a PNA conjugated to different CPPs to inhibit the replication of duck hepatitis B virus (DHBV), a reference model for human HBV infection. The in vivo administration of PNA-CPP conjugates to neonatal ducklings showed that they reached the liver and inhibited DHBV replication. Interestingly, our results indicated also that a modified CPP (CatLip) alone, in the absence of its PNA cargo, was able to drastically inhibit late stages of DHBV replication. In the mouse model, conjugation of HBV DNA vaccine to modified CS (Man-CS-Phe) improved cellular and humoral responses to plasmid-encoded antigen. Moreover, other systems for gene delivery were investigated including CPP-modified CS and cationic nanoparticles. The results showed that these nonviral vectors considerably increased plasmid DNA uptake and expression. Collectively promising results obtained in preclinical studies suggest the usefulness of these safe delivery systems for the development of novel therapeutics against chronic hepatitis B.
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Kamei N, Aoyama Y, Khafagy ES, Henmi M, Takeda-Morishita M. Effect of different intestinal conditions on the intermolecular interaction between insulin and cell-penetrating peptide penetratin and on its contribution to stimulation of permeation through intestinal epithelium. Eur J Pharm Biopharm 2015; 94:42-51. [PMID: 25960330 DOI: 10.1016/j.ejpb.2015.04.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/28/2015] [Accepted: 04/30/2015] [Indexed: 11/17/2022]
Abstract
Our recent studies have shown that the coadministration of cell-penetrating peptides (CPPs) is a potential strategy for oral delivery of peptide- and protein-based biopharmaceuticals. The intermolecular interaction between drug and CPP is an essential factor in the effective delivery of these drugs, but the characteristics of the interaction under the conditions of the intestinal lumen remain unknown. In this study, therefore, we examined the characteristics of binding of the amphipathic CPP penetratin to insulin and the efficiency of its enhancement of epithelial insulin transport at different pH and in simulated intestinal fluids (SIFs). The binding between insulin and penetratin was pH dependent and particularly decreased at pH 5.0. In addition, we clarified that the sodium taurocholate (NaTC) present in two types of SIF (fasted-state SIF [FaSSIF] and fed-state SIF [FeSSIF]) affected binding efficiency. However, the permeation of insulin through a Caco-2 cell monolayer was significantly facilitated by coincubation with l- or d-penetratin at various pH values. Moreover, the permeation-stimulating effect of l-penetratin was observed in FaSSIF containing NaTC and lecithin, but not in 3mM NaTC solution, suggesting that the presence of lecithin was the key factor in maintaining the ability of penetratin to enhance the intestinal absorption of biopharmaceuticals. This report describes the essential considerations for in vivo use and clinical application of a CPP-based oral delivery strategy.
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Jittavisutthikul S, Thanongsaksrikul J, Thueng-In K, Chulanetra M, Srimanote P, Seesuay W, Malik AA, Chaicumpa W. Humanized-VHH transbodies that inhibit HCV protease and replication. Viruses 2015; 7:2030-56. [PMID: 25903832 PMCID: PMC4411689 DOI: 10.3390/v7042030] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/12/2015] [Accepted: 04/14/2015] [Indexed: 12/28/2022] Open
Abstract
There is a need for safe and broadly effective anti-HCV agents that can cope with genetic multiplicity and mutations of the virus. In this study, humanized-camel VHHs to genotype 3a HCV serine protease were produced and were linked molecularly to a cell penetrating peptide, penetratin (PEN). Human hepatic (Huh7) cells transfected with the JFH-1 RNA of HCV genotype 2a and treated with the cell penetrable nanobodies (transbodies) had a marked reduction of the HCV RNA intracellularly and in their culture fluids, less HCV foci inside the cells and less amounts of HCV core antigen in culture supernatants compared with the infected cells cultured in the medium alone. The PEN-VHH-treated-transfected cells also had up-regulation of the genes coding for the host innate immune response (TRIF, TRAF3, IRF3, IL-28B and IFN-β), indicating that the cell penetrable nanobodies rescued the host innate immune response from the HCV mediated-suppression. Computerized intermolecular docking revealed that the VHHs bound to residues of the protease catalytic triad, oxyanion loop and/or the NS3 N-terminal portion important for non-covalent binding of the NS4A protease cofactor protein. The so-produced transbodies have high potential for testing further as a candidate for safe, broadly effective and virus mutation tolerable anti-HCV agents.
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Sehnert B, Burkhardt H, Dübel S, Voll RE. The "sneaking-ligand" approach: cell-type specific inhibition of the classical NF-κB pathway. Methods Mol Biol 2015; 1280:559-78. [PMID: 25736772 DOI: 10.1007/978-1-4939-2422-6_33] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The intracellular delivery of molecules across the plasma membrane represents a major obstacle. The conjugation of cell-permeable peptides (CPPs) to proteins promotes the uptake and internalization. However, uptake of CPPs is receptor independent and not cell-type specific. Recently, we established the "sneaking-ligand" approach which is based on multimodular recombinant fusion proteins that consist of three modules connected with serine-glycine linkers. Module one is responsible for receptor-mediated endocytosis; module two supports translocation into the cytoplasm so that the effector module three can interact with its binding partner in the cytoplasm. For NF-κB inhibition, we described an NF-κB inhibitor that targets selectively the activated endothelium via an oligopeptide motif. Upon E-selectin-mediated endocytosis, the Pseudomonas exotoxin A domain II (ETAII) translocates the NEMO-binding peptide to the cytoplasm interfering with IκB kinase complex assembly. Inflammatory autoimmune diseases are triggered, but also resolved by a variety of cell types. Therefore, the inhibition of NF-κB should be restricted to those cells that are crucially involved in the pathogenesis of inflammatory diseases. A general blockade of NF-κB may result in severe immunosuppression and possibly in organ dysfunction or damage. The "sneaking-ligand" approach could minimize the risks of therapeutic interventions and identify disease-relevant cell types. Here we describe the recombinant expression and purification of the E-selectin-specific "sneaking-ligand construct" (SLC1) and its ability to inhibit cytokine-induced NF-κB activation in vitro.
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Hauff SJ, Raju SC, Orosco RK, Gross AM, Diaz-Perez JA, Savariar E, Nashi N, Hasselman J, Whitney M, Myers JN, Lippman SM, Tsien RY, Ideker T, Nguyen QT. Matrix-metalloproteinases in head and neck carcinoma-cancer genome atlas analysis and fluorescence imaging in mice. Otolaryngol Head Neck Surg 2014; 151:612-8. [PMID: 25091190 PMCID: PMC4469264 DOI: 10.1177/0194599814545083] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 07/07/2014] [Indexed: 12/22/2022]
Abstract
OBJECTIVE (1) Obtain matrix-metalloproteinase (MMP) expression profiles for head and neck squamous cell carcinoma (HNSCC) specimens from the Cancer Genomic Atlas (TCGA). (2) Demonstrate HNSCC imaging using MMP-cleavable, fluorescently labeled ratiometric activatable cell-penetrating peptide (RACPP). STUDY DESIGN Retrospective human cohort study; prospective animal study. SETTING Translational research laboratory. SUBJECTS AND METHODS Patient clinical data and mRNA expression levels of MMP genes were downloaded from TCGA data portal. RACPP provides complementary ratiometric fluorescent contrast (increased Cy5 and decreased Cy7 intensities) when cleaved by MMP2/9. HNSCC-tumor bearing mice were imaged in vivo after RACPP injection. Histology was evaluated by a pathologist blinded to experimental conditions. Zymography confirmed MMP-2/9 activity in xenografts. RACPP was applied to homogenized human HNSCC specimens, and ratiometric fluorescent signal was measured on a microplate reader for ex vivo analysis. RESULTS Expression of multiple MMPs including MMP2/9 is greater in patient HNSCC tumors than matched control tissue. In patients with human papilloma virus positive (HPV+) tumors, higher MMP2 and MMP14 expression correlates with worse 5-year survival. Orthotopic tongue HNSCC xenografts showed excellent ratiometric fluorescent labeling with MMP2/9-cleavable RACPP (sensitivity = 95.4%, specificity = 95.0%). Fluorescence ratios were greater in areas of higher tumor burden (P < .03), which is useful for intraoperative margin assessment. Ex vivo, human HNSCC specimens showed greater cleavage of RACPP when compared to control tissue (P = .009). CONCLUSIONS Human HNSCC tumors show increased mRNA expression of multiple MMPs including MMP2/9. We used RACPP, a ratiometric fluorescence assay of MMP2/9 activity, to show improved occult tumor identification and margin clearance. Ex vivo assays using RACPP in biopsy specimens may identify patients who will benefit from intraoperative RACPP use.
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Evuarherhe O, Barker GRI, Savalli G, Warburton EC, Brown MW. Early memory formation disrupted by atypical PKC inhibitor ZIP in the medial prefrontal cortex but not hippocampus. Hippocampus 2014; 24:934-42. [PMID: 24729442 PMCID: PMC4285083 DOI: 10.1002/hipo.22281] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2014] [Indexed: 12/12/2022]
Abstract
Atypical isoforms of protein kinase C (aPKCs; particularly protein kinase M zeta: PKMζ) have been hypothesized to be necessary and sufficient for the maintenance of long-term potentiation (LTP) and long term memory by maintaining postsynaptic AMPA receptors via the GluA2 subunit. A myristoylated PKMζ pseudosubstrate peptide (ZIP) blocks PKMζ activity. We examined the actions of ZIP in medial prefrontal cortex (mPFC) and hippocampus in associative recognition memory in rats during early memory formation and memory maintenance. ZIP infusion in either hippocampus or mPFC impaired memory maintenance. However, early memory formation was impaired by ZIP in mPFC but not hippocampus; and blocking GluA2-dependent removal of AMPA receptors did not affect this impairment caused by ZIP in the mPFC. The findings indicate: (i) a difference in the actions of ZIP in hippocampus and medial prefrontal cortex, and (ii) a GluA2-independent target of ZIP (possibly PKCλ) in the mPFC during early memory formation.
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Rivalin R, Lepinoux-Chambaud C, Eyer J, Savagner F. The NFL-TBS.40-63 anti-glioblastoma peptide disrupts microtubule and mitochondrial networks in the T98G glioma cell line. PLoS One 2014; 9:e98473. [PMID: 24896268 PMCID: PMC4045719 DOI: 10.1371/journal.pone.0098473] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 05/02/2014] [Indexed: 11/18/2022] Open
Abstract
Despite aggressive therapies, including combinations of surgery, radiotherapy and chemotherapy, glioblastoma remains a highly aggressive brain cancer with the worst prognosis of any central nervous system disease. We have previously identified a neurofilament-derived cell-penetrating peptide, NFL-TBS.40-63, that specifically enters by endocytosis in glioblastoma cells, where it induces microtubule destruction and inhibits cell proliferation. Here, we explore the impact of NFL-TBS.40-63 peptide on the mitochondrial network and its functions by using global cell respiration, quantitative PCR analysis of the main actors directing mitochondrial biogenesis, western blot analysis of the oxidative phosphorylation (OXPHOS) subunits and confocal microscopy. We show that the internalized peptide disturbs mitochondrial and microtubule networks, interferes with mitochondrial dynamics and induces a rapid depletion of global cell respiration. This effect may be related to reduced expression of the NRF-1 transcription factor and of specific miRNAs, which may impact mitochondrial biogenesis, in regard to default mitochondrial mobility.
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Kerkis I, Hayashi MAF, Prieto da Silva ARB, Pereira A, De Sá Júnior PL, Zaharenko AJ, Rádis-Baptista G, Kerkis A, Yamane T. State of the art in the studies on crotamine, a cell penetrating peptide from South American rattlesnake. BIOMED RESEARCH INTERNATIONAL 2014; 2014:675985. [PMID: 24551848 PMCID: PMC3914522 DOI: 10.1155/2014/675985] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 08/05/2013] [Accepted: 08/08/2013] [Indexed: 12/03/2022]
Abstract
Animal venoms comprise a naturally selected cocktail of bioactive peptides/proteins and other molecules, each of which playing a defined role thanks to the highly specific interactions with diverse molecular targets found in the prey. Research focused on isolation, structural, and functional characterizations of novel natural biologics (bioactive peptides/proteins from natural sources) has a long way to go through from the basic science to clinical applications. Herein, we overview the structural and functional characteristics of the myoneurotoxin crotamine, firstly isolated from the South American rattlesnake venom. Crotamine is the first venom peptide classified as a natural cell penetrating and antimicrobial peptide (CPP and AMP) with a more pronounced antifungal activity. In contrast to other known natural CPPs and AMPs, crotamine demonstrates a wide spectrum of biological activities with potential biotechnological and therapeutic values. More recent studies have demonstrated the selective in vitro anticancer activity of crotamine. In vivo, using a murine melanoma model, it was shown that crotamine delays tumor implantation, inhibits tumor cells proliferation, and also increases the survival of mice engrafted with subcutaneous melanoma. The structural and functional properties and also the possible biotechnological applications of minimized molecules derived from crotamine are also discussed.
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Ran R, Zhang L, Tang J, Yin YJ, Qin Y, Liu YY, Zhang ZR, He Q. Enhanced tumor accumulation and cellular uptake of liposomes modified with ether-bond linked cholesterol derivatives. DIE PHARMAZIE 2013; 68:668-674. [PMID: 24020121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Novel liposomal formulations based on cholesterol modification had been designed previously by our lab, but we found them with a poor stability and short half-life, especially in blood circulation. The results might be attributed to the hydrolysis of ester linked cholesterol derivatives by esterase in plasma. Thus, in this study, we newly synthesized ether-linked cholesterol derivatives and compared them to other preparations. A comparison with the substrate cholesterol-PEG2000-maleimide showed that ether-linked cholesterol-PEG2000-maleimide could relatively maintain integrity in serum, with only a small mottle emerging on TLC (thin-layer chromatography) plates through the experiment. Then a cell-penetrating peptide TAT was attached to the distal end of CHO-PEG2000 to prepare liposomes and to further evaluate the two cholesterol derivatives. Optimized liposomes (65:35, lipid/cholesterol, molar ratio) composed of 3% CHO-PEG2000 and 3% CHO-PEG2000-TAT showed good stability in 50%FBS (fetal bovine serum). In vitro experiments showed that as incubation time prolonged, ether-linked-TAT LIP showed a 3.67-fold higher uptake amount than ester-linked-TAT LIP. In vivo, ether-linked-TAT LIP accumulated better in tumors and had a 40% higher cellular uptake amount. Altogether, we could conclude that our newly ether-linked cholesterol derivatives possessed better stability especially in blood circulation which led to increased tumor cellular uptake in vitro and in vivo. Our study may offer a better way in cholesterol modification to prepare functionalized liposomes.
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Liu X, Zhu H, Jin Q, Zhou W, Colvin VL, Ji J. Small and stable phosphorylcholine zwitterionic quantum dots for weak nonspecific phagocytosis and effective Tat peptide functionalization. Adv Healthc Mater 2013. [PMID: 23184894 DOI: 10.1002/adhm.201200210] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Facile surface modification of quantum dots (QDs) to make them water-soluble, small, stable, antibiofouling, and functional is crucial for their biological applications. This study demonstrates a simple ligand-exchange reaction to convert hydrophobic CdSe/ZnS QDs into water-soluble QDs using amphiphilic, zwitterionic 11-mercaptoundecylphosphorylcholine (HS-PC). The phosphorylcholine (PC)-modified QDs (QD-PC) possess several advantages, such as small hydrodynamic diameter, good resistance to pH variations and high salinity, excellent stability in 100% human plasma, and low protein adsorption. Importantly, the PC modification endows the QDs with very low, nonspecific interaction with cells, and strongly minimizes nonspecific phagocytosis of QDs by macrophages. In addition, cell penetrating Tat peptide functionalized QDs can be easily produced by mixing Tat with HS-PC with various ratios, which is proved to effectively enhance QD ability to enter cells and accumulate around perinuclear region. Compared to traditional mercaptoundecanoic acid (MUA) modification, PC modification not only makes the cell penetrating QDs more stable and brighter, but also provides the Tat- and PC-conjugated QDs with much lower nonspecific phagocytic uptake than the Tat- and MUA-conjugated ones. This research will provide insights into designing suitable ligands for surface modification of QDs and improving biofunctional QD performance in biological applications.
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Savariar EN, Felsen CN, Nashi N, Jiang T, Ellies LG, Steinbach P, Tsien RY, Nguyen QT. Real-time in vivo molecular detection of primary tumors and metastases with ratiometric activatable cell-penetrating peptides. Cancer Res 2013; 73:855-64. [PMID: 23188503 PMCID: PMC3799878 DOI: 10.1158/0008-5472.can-12-2969] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Management of metastatic disease is integral to cancer treatment. Evaluation of metastases often requires surgical removal of all anatomically susceptible lymph nodes for ex vivo pathologic examination. We report a family of novel ratiometric activatable cell-penetrating peptides, which contain Cy5 as far red fluorescent donor and Cy7 as near-infrared fluorescent acceptor. Cy5 is quenched in favor of Cy7 re-emission until the intervening linker is cut by tumor-associated matrix metalloproteinases-2 and 9 (MMP2,9) or elastases. Such cleavage increases the Cy5:Cy7 emission ratio 40-fold and triggers tissue retention of the Cy5-containing fragment. This ratiometric increase provides an accelerated and quantifiable metric to identify primary tumors and metastases to liver and lymph nodes with increased sensitivity and specificity. This technique represents a significant advance over existing nonratiometric protease sensors and sentinel lymph node detection methods, which give no information about cancer invasion.
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Lee CC, Sun Y, Huang H. How type II diabetes-related islet amyloid polypeptide damages lipid bilayers. Biophys J 2012; 102:1059-68. [PMID: 22404928 PMCID: PMC3296043 DOI: 10.1016/j.bpj.2012.01.039] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 01/18/2012] [Accepted: 01/23/2012] [Indexed: 10/28/2022] Open
Abstract
A leading hypothesis for the decimation of insulin-producing β-cells in type 2 diabetes attributes the cause to islet amyloid polypeptide (IAPP) for its deleterious effects on the cell membranes. This idea has produced extensive investigations on human IAPP (hIAPP) and its interactions with lipid bilayers. However, it is still difficult to correlate the peptide-lipid interactions with its effects on islet cells in culture. The hIAPP fibrils have been shown to interact with lipids and damage lipid bilayers, but appear to have no effect on islet cells in culture. Thus, a modified amyloid hypothesis assumes that the toxicity is caused by hIAPP oligomers, which are not preamyloid fibrils or protofibrils. However, so far such oligomers have not been isolated or identified. The hIAPP monomers also bind to lipid bilayers, but the mode of interaction is not clear. Here, we performed two types of experiments that, to our knowledge, have not been done before. We used x-ray diffraction, in conjunction with circular dichroism measurement, to reveal the location of the peptide bound to a lipid bilayer. We also investigated the effects of hIAPP on giant unilamellar vesicles at various peptide concentrations. We obtained the following qualitative results. Monomeric hIAPP binds within the headgroup region and expands the membrane area of a lipid bilayer. At low concentrations, such binding causes no leakage or damage to the lipid bilayer. At high concentrations, the bound peptides transform to β-aggregates. The aggregates exit the headgroup region and bind to the surface of lipid bilayers. The damage by the surface bound β-aggregates depends on the aggregation size. The initial aggregation extracts lipid molecules, which probably causes ion permeation, but no molecular leakage. However, the initial β-aggregates serve as the seed for larger fibrils, in the manner of the Jarrett-Lansbury seeded-polymerization model, that eventually disintegrate lipid bilayers by electrostatic and hydrophobic interactions.
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Child HW, Del Pino PA, De La Fuente JM, Hursthouse AS, Stirling D, Mullen M, McPhee GM, Nixon C, Jayawarna V, Berry CC. Working together: the combined application of a magnetic field and penetratin for the delivery of magnetic nanoparticles to cells in 3D. ACS NANO 2011; 5:7910-9. [PMID: 21894941 DOI: 10.1021/nn202163v] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nanoparticles (NPs) are currently being developed as vehicles for in vivo drug delivery. Two of the biggest barriers facing this therapy are the site-specific targeting and consequent cellular uptake of drug-loaded NPs(1). In vitro studies in 2D cell cultures have shown that an external magnetic field (MF) and functionalization with cell-penetrating peptides (CPPs) have the capacity to overcome these barriers. This study aimed to investigate if the potential of these techniques, which has been reported in 2D, can be successfully applied to cells growing in a 3D environment. As such, this study provides a more realistic assessment of how these techniques might perform in future clinical settings. The effect of a MF and/or penetratin attachment on the uptake of 100 and 200 nm fluorescent iron oxide magnetic NPs (mNPs) into a fibroblast-seeded 3D collagen gel was quantified by inductively coupled plasma mass spectrometry. The most suitable mNP species was further investigated by fluorescence microscopy, histology, confocal microscopy, and TEM. Results show that gel mNP uptake occurred on average twice as fast in the presence of a MF and up to three times faster with penetratin attachment. In addition, a MF increased the distance of mNP travel through the gel, while penetratin increased mNP cell localization. This work is one of the first to demonstrate that MFs and CPPs can be effectively translated for use in 3D systems and, if applied together, will make excellent partners to achieve therapeutic drug delivery in vivo.
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Zou F, Schäfer N, Palesch D, Brücken R, Beck A, Sienczyk M, Kalbacher H, Sun Z, Boehm BO, Burster T. Regulation of cathepsin G reduces the activation of proinsulin-reactive T cells from type 1 diabetes patients. PLoS One 2011; 6:e22815. [PMID: 21850236 PMCID: PMC3151250 DOI: 10.1371/journal.pone.0022815] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 07/01/2011] [Indexed: 11/18/2022] Open
Abstract
Autoantigenic peptides resulting from self-proteins such as proinsulin are important players in the development of type 1 diabetes mellitus (T1D). Self-proteins can be processed by cathepsins (Cats) within endocytic compartments and loaded to major histocompatibility complex (MHC) class II molecules for CD4+ T cell inspection. However, the processing and presentation of proinsulin by antigen-presenting cells (APC) in humans is only partially understood. Here we demonstrate that the processing of proinsulin by B cell or myeloid dendritic cell (mDC1)-derived lysosomal cathepsins resulted in several proinsulin-derived intermediates. These intermediates were similar to those obtained using purified CatG and, to a lesser extent, CatD, S, and V in vitro. Some of these intermediates polarized T cell activation in peripheral blood mononuclear cells (PBMC) from T1D patients indicative for naturally processed T cell epitopes. Furthermore, CatG activity was found to be elevated in PBMC from T1D patients and abrogation of CatG activity resulted in functional inhibition of proinsulin-reactive T cells. Our data suggested the notion that CatG plays a critical role in proinsulin processing and is important in the activation process of diabetogenic T cells.
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93
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Bolhassani A, Safaiyan S, Rafati S. Improvement of different vaccine delivery systems for cancer therapy. Mol Cancer 2011; 10:3. [PMID: 21211062 PMCID: PMC3024302 DOI: 10.1186/1476-4598-10-3] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 01/07/2011] [Indexed: 12/18/2022] Open
Abstract
Cancer vaccines are the promising tools in the hands of the clinical oncologist. Many tumor-associated antigens are excellent targets for immune therapy and vaccine design. Optimally designed cancer vaccines should combine the best tumor antigens with the most effective immunotherapy agents and/or delivery strategies to achieve positive clinical results. Various vaccine delivery systems such as different routes of immunization and physical/chemical delivery methods have been used in cancer therapy with the goal to induce immunity against tumor-associated antigens. Two basic delivery approaches including physical delivery to achieve higher levels of antigen production and formulation with microparticles to target antigen-presenting cells (APCs) have demonstrated to be effective in animal models. New developments in vaccine delivery systems will improve the efficiency of clinical trials in the near future. Among them, nanoparticles (NPs) such as dendrimers, polymeric NPs, metallic NPs, magnetic NPs and quantum dots have emerged as effective vaccine adjuvants for infectious diseases and cancer therapy. Furthermore, cell-penetrating peptides (CPP) have been known as attractive carrier having applications in drug delivery, gene transfer and DNA vaccination. This review will focus on the utilization of different vaccine delivery systems for prevention or treatment of cancer. We will discuss their clinical applications and the future prospects for cancer vaccine development.
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94
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Peng J, Zu L, Fang W, Huang L, Wang Y, He D. Selective cleavage of protonated penetratin and its substitutes under low-energy collision-induced dissociation condition. JOURNAL OF MASS SPECTROMETRY : JMS 2010; 45:627-634. [PMID: 20527031 DOI: 10.1002/jms.1748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
An understanding of the dissociation of penetratin is important for improving its metabolic stability and cargo-delivery efficiency. In this study, we describe the selective cleavage of the K15-K16 amide bond of penetratin under the low-energy collision-induced dissociation condition in mass spectrometry. A variety of penetratin substitutes have been studied in which key basic amino acids have been substituted within the sequence. The calculated structure indicates that an alpha-helix structure prevents the fragmentation of the central peptide domain and the side chain of lysine is involved in the proton translocation process.
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95
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Nakase I, Futaki S. [Development of membrane-permeable peptide vectors and their internalization mechanisms]. SEIKAGAKU. THE JOURNAL OF JAPANESE BIOCHEMICAL SOCIETY 2009; 81:992-995. [PMID: 19999581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
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96
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Yesylevskyy S, Marrink SJ, Mark AE. Alternative mechanisms for the interaction of the cell-penetrating peptides penetratin and the TAT peptide with lipid bilayers. Biophys J 2009; 97:40-9. [PMID: 19580742 PMCID: PMC2711361 DOI: 10.1016/j.bpj.2009.03.059] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 03/25/2009] [Accepted: 03/30/2009] [Indexed: 11/21/2022] Open
Abstract
Cell-penetrating peptides (CPPs) have recently attracted much interest due to their apparent ability to penetrate cell membranes in an energy-independent manner. Here molecular-dynamics simulation techniques were used to study the interaction of two CPPs: penetratin and the TAT peptide with 1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) phospolipid bilayers shed light on alternative mechanisms by which these peptides might cross biological membranes. In contrast to previous simulation studies of charged peptides interacting with lipid bilayers, no spontaneous formation of transmembrane pores was observed. Instead, the simulations suggest that the peptides may enter the cell by micropinocytosis, whereby the peptides induce curvature in the membrane, ultimately leading to the formation of small vesicles within the cell that encapsulate the peptides. Specifically, multiple peptides were observed to induce large deformations in the lipid bilayer that persisted throughout the timescale of the simulations (hundreds of nanoseconds). Pore formation could be induced in simulations in which an external potential was used to pull a single penetratin or TAT peptide into the membrane. With the use of umbrella-sampling techniques, the free energy of inserting a single penetratin peptide into a DPPC bilayer was estimated to be approximately 75 kJmol(-1), which suggests that the spontaneous penetration of single peptides would require a timescale of at least seconds to minutes. This work also illustrates the extent to which the results of such simulations can depend on the initial conditions, the extent of equilibration, the size of the system, and the conditions under which the simulations are performed. The implications of this with respect to the current systems and to simulations of membrane-peptide interactions in general are discussed.
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97
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Jankowski MP, McIlwrath SL, Jing X, Cornuet PK, Salerno KM, Koerber HR, Albers KM. Sox11 transcription factor modulates peripheral nerve regeneration in adult mice. Brain Res 2009; 1256:43-54. [PMID: 19133245 PMCID: PMC2666926 DOI: 10.1016/j.brainres.2008.12.032] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Revised: 11/20/2008] [Accepted: 12/07/2008] [Indexed: 12/17/2022]
Abstract
The ability of adult peripheral sensory neurons to undergo functional and anatomical recovery following nerve injury is due in part to successful activation of transcriptional regulatory pathways. Previous in vitro evidence had suggested that the transcription factor Sox11, a HMG-domain containing protein that is highly expressed in developing sensory neurons, is an important component of this regenerative transcriptional control program. To further test the role of Sox11 in an in vivo system, we developed a new approach to specifically target small interfering RNAs (siRNAs) conjugated to the membrane permeable molecule Penetratin to injured sensory afferents. Injection of Sox11 siRNAs into the mouse saphenous nerve caused a transient knockdown of Sox11 mRNA that transiently inhibited in vivo regeneration. Electron microscopic level analysis of Sox11 RNAi-injected nerves showed that regeneration of myelinated and unmyelinated axons was inhibited. Nearly all neurons in ganglia of crushed nerves that were Sox11 immunopositive showed colabeling for the stress and injury-associated activating transcription factor 3 (ATF3). In addition, treatment with Sox11 siRNAs in vitro and in vivo caused a transcriptional and translational level reduction in ATF3 expression. These anatomical and expression data support an intrinsic role for Sox11 in events that underlie successful regeneration following peripheral nerve injury.
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98
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Sarantseva SV, Bol'shakova OI, Timoshenko SI, Kolobov AA, Vitek MP, Shvartsman AL. [Protein transduction domain peptide mediates delivery to the brain via the blood-brain barrier in Drosophila]. BIOMEDITSINSKAIA KHIMIIA 2009; 55:41-49. [PMID: 19351032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Protein transduction domain (PTD)-peptides greatly facilitate the delivery of high molecular weight macromolecules across the blood-brain barrier (BBB). This BBB-transport function is highly desirable and helps to enable the development of new therapeutics for treatment of brain disorders. However, the drug discovery process is limited by the generation of a simple and reliable BBB model that is amenable to testing of large number of samples and simultaneously, reproduces the physiological and functional characteristics of the human BBB. To address these challenges, we have studied whether the PTD-peptide penetratin, derived from a Drosophila Antennapedia homeodomain protein, is capable of crossing the BBB in Drosophila while carrying a cargo into the fly brain. An initial in vivo experiment in Drosophila showed that abdominal injection of biotin-tagged penetratin permeated the BBB. The same effect was observed for biotin-tagged penetratin fused with apoE mimetic peptide with demonstrated anti-inflammatory and neuroprotective activities.
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99
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Su Y, Mani R, Hong M. Asymmetric insertion of membrane proteins in lipid bilayers by solid-state NMR paramagnetic relaxation enhancement: a cell-penetrating Peptide example. J Am Chem Soc 2008; 130:8856-64. [PMID: 18597439 PMCID: PMC4083468 DOI: 10.1021/ja802383t] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A novel solid-state NMR technique for identifying the asymmetric insertion depths of membrane proteins in lipid bilayers is introduced. By applying Mn (2+) ions on the outer but not the inner leaflet of lipid bilayers, the sidedness of protein residues in the lipid bilayer can be determined through paramagnetic relaxation enhancement (PRE) effects. Protein-free lipid membranes with one-side Mn (2+)-bound surfaces exhibit significant residual (31)P and lipid headgroup (13)C intensities, in contrast to two-side Mn (2+)-bound membranes, where lipid headgroup signals are mostly suppressed. Applying this method to a cell-penetrating peptide, penetratin, we found that at low peptide concentrations, penetratin is distributed in both leaflets of the bilayer, in contrast to the prediction of the electroporation model, which predicts that penetratin binds to only the outer lipid leaflet at low peptide concentrations to cause an electric field that drives subsequent peptide translocation. The invalidation of the electroporation model suggests an alternative mechanism for intracellular import of penetratin, which may involve guanidinium-phosphate complexation between the peptide and the lipids.
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100
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Lamazière A, Wolf C, Lambert O, Chassaing G, Trugnan G, Ayala-Sanmartin J. The homeodomain derived peptide Penetratin induces curvature of fluid membrane domains. PLoS One 2008; 3:e1938. [PMID: 18398464 PMCID: PMC2276244 DOI: 10.1371/journal.pone.0001938] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Accepted: 02/27/2008] [Indexed: 11/23/2022] Open
Abstract
Background Protein membrane transduction domains that are able to cross the plasma membrane are present in several transcription factors, such as the homeodomain proteins and the viral proteins such as Tat of HIV-1. Their discovery resulted in both new concepts on the cell communication during development, and the conception of cell penetrating peptide vectors for internalisation of active molecules into cells. A promising cell penetrating peptide is Penetratin, which crosses the cell membranes by a receptor and metabolic energy-independent mechanism. Recent works have claimed that Penetratin and similar peptides are internalized by endocytosis, but other endocytosis-independent mechanisms have been proposed. Endosomes or plasma membranes crossing mechanisms are not well understood. Previously, we have shown that basic peptides induce membrane invaginations suggesting a new mechanism for uptake, “physical endocytosis”. Methodology/Principal Findings Herein, we investigate the role of membrane lipid phases on Penetratin induced membrane deformations (liquid ordered such as in “raft” microdomains versus disordered fluid “non-raft” domains) in membrane models. Experimental data show that zwitterionic lipid headgroups take part in the interaction with Penetratin suggesting that the external leaflet lipids of cells plasma membrane are competent for peptide interaction in the absence of net negative charges. NMR and X-ray diffraction data show that the membrane perturbations (tubulation and vesiculation) are associated with an increase in membrane negative curvature. These effects on curvature were observed in the liquid disordered but not in the liquid ordered (raft-like) membrane domains. Conclusions/Significance The better understanding of the internalisation mechanisms of protein transduction domains will help both the understanding of the mechanisms of cell communication and the development of potential therapeutic molecular vectors. Here we showed that the membrane targets for these molecules are preferentially the fluid membrane domains and that the mechanism involves the induction of membrane negative curvature. Consequences on cellular uptake are discussed.
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