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1.
Biomaterials ; 312: 122740, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39096839

ABSTRACT

Metastasis stands as the primary contributor to mortality associated with tumors. Chemotherapy and immunotherapy are frequently utilized in the management of metastatic solid tumors. Nevertheless, these therapeutic modalities are linked to serious adverse effects and limited effectiveness in preventing metastasis. Here, we report a novel therapeutic strategy named starvation-immunotherapy, wherein an immune checkpoint inhibitor is combined with an ultra-long-acting L-asparaginase that is a fusion protein comprising L-asparaginase (ASNase) and an elastin-like polypeptide (ELP), termed ASNase-ELP. ASNase-ELP's thermosensitivity enables it to generate an in-situ depot following an intratumoral injection, yielding increased dose tolerance, improved pharmacokinetics, sustained release, optimized biodistribution, and augmented tumor retention compared to free ASNase. As a result, in murine models of oral cancer, melanoma, and cervical cancer, the antitumor efficacy of ASNase-ELP by selectively and sustainably depleting L-asparagine essential for tumor cell survival was substantially superior to that of ASNase or Cisplatin, a first-line anti-solid tumor medicine, without any observable adverse effects. Furthermore, the combination of ASNase-ELP and an immune checkpoint inhibitor was more effective than either therapy alone in impeding melanoma metastasis. Overall, the synergistic strategy of starvation-immunotherapy holds excellent promise in reshaping the therapeutic landscape of refractory metastatic tumors and offering a new alternative for next-generation oncology treatments.


Subject(s)
Asparaginase , Immune Checkpoint Inhibitors , Immunotherapy , Animals , Asparaginase/therapeutic use , Asparaginase/pharmacology , Asparaginase/chemistry , Immunotherapy/methods , Female , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Mice , Humans , Cell Line, Tumor , Drug Synergism , Elastin/chemistry , Elastin/metabolism , Neoplasm Metastasis , Mice, Inbred C57BL , Mice, Inbred BALB C , Neoplasms/drug therapy , Neoplasms/pathology , Tissue Distribution
2.
Rapid Commun Mass Spectrom ; 38(21): e9905, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39223901

ABSTRACT

RATIONALE: Elastin-like polypeptides (ELPs) are elastic and thermoresponsive biopolymers composed of VPGXG repeats (X can be any amino acid except proline), used in biomedical applications, for example, tissue engineering and drug delivery. As different variants of ELP are mostly produced fermentatively, there is a need for the development of analysis methods that allow for absolute protein quantification in both complex matrices and purified samples and MW determination of the final products. METHODS: ELPs were intracellularly expressed in Escherichia coli quantified after cell lysis and enzymatic digestion using a proline-specific protease ProAlanase (Promega) at acidic conditions. Resulting peptides were separated by liquid chromatography, and mass spectrometry analysis was conducted by electrospray ionization high-resolution mass spectrometry using an Orbitrap mass spectrometer. The addition of a stable isotopically labeled internal standard enabled quantification in complex matrices. Prior to intact mass analysis, ELPs were purified from fermentation broth by inverse temperature cycling. Intact protein analysis was performed using reversed-phase liquid chromatography, and mass spectrometry analysis was conducted by electrospray ionization high-resolution mass spectrometry using a time-of-flight mass spectrometer. RESULTS: Absolute quantification of ELPs was achieved by utilizing ELP-specific properties, that is, proline-rich, soluble at low pH and low temperature. The repetitive nature of ELPs allows for sensitivity increase and use of higher dilution factors to minimize the matrix effects. Despite the lack of amino acids with charged side chains (Arg, His, Lys, Asp, and Glu) in ELP, we demonstrated successful intact protein analysis using reversed-phase LC coupled to electrospray ionization TOF MS. Moreover, truncated protein forms could be chromatographically separated and characterized as well as N-terminal modifications. CONCLUSIONS: Both methods combined enabled quantitative and qualitative characterization of fermentatively produced ELPs.


Subject(s)
Elastin , Escherichia coli , Peptides , Elastin/chemistry , Escherichia coli/chemistry , Peptides/chemistry , Peptides/analysis , Hydrogen-Ion Concentration , Spectrometry, Mass, Electrospray Ionization/methods , Cold Temperature , Chromatography, Liquid/methods , Chromatography, Reverse-Phase/methods , Elastin-Like Polypeptides
3.
Biomacromolecules ; 25(9): 6127-6134, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39105695

ABSTRACT

We present a straightforward strategy for constructing giant, multicompartmentalized vesicles using recombinant fusion proteins. Our method leverages the self-assembly of globule-zipper-elastin-like polypeptide fusion protein complexes in aqueous conditions, eliminating the need for organic solvents and chemical conjugation. By employing the thin-film rehydration method, we have successfully encapsulated a diverse range of bioactive macromolecules and engineered organelle-like compartments─ranging from soluble proteins and coacervate droplets to vesicles─within these protein-assembled giant vesicles. This approach also facilitates the integration of water-soluble block copolymers, enhancing the structural stability and functional versatility of the vesicles. Our results suggest that these multicompartment giant protein vesicles not only mimic the complex architecture of living cells but also support biochemically distinct reactions regulated by functionally folded proteins, providing a robust model for studying cellular processes and designing microreactor systems. This work highlights the transformative potential of self-assembling recombinant fusion proteins in artificial cell design.


Subject(s)
Recombinant Fusion Proteins , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Elastin/chemistry , Elastin/genetics , Peptides/chemistry
4.
Biomacromolecules ; 25(9): 5729-5744, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39185801

ABSTRACT

Nucleic acid (NA)-based therapies are revolutionizing biomedical research through their ability to control cellular functions at the genetic level. This work demonstrates a versatile elastin-like polypeptide (ELP) carrier system using a layer-by-layer (LbL) formulation approach that delivers NA cargos ranging in size from siRNA to plasmids. The components of the system can be reconfigured to modulate the biochemical and biophysical characteristics of the carrier for engaging the unique features of the biological target. We show the physical characterization and biological performance of LbL ELP nucleic acid nanoparticles (LENNs) in murine and human bladder tumor cell lines. Targeting bladder tumors is difficult owing to the constant influx of urine into the bladder, leading to low contact times (typically <2 h) for therapeutic agents delivered via intravesical instillation. LENN complexes bind to bladder tumor cells within 30 min and become rapidly internalized to release their NA cargo within 60 min. Our data show that a readily adaptable NA-delivery system has been created that is flexible in its targeting ability, cargo size, and disassembly kinetics. This approach provides an alternative path to either lipid nanoparticle formulations that suffer from inefficiency and physicochemical instability or viral vectors that are plagued by manufacturing and immune rejection challenges. This agile ELP-based nanocarrier provides an alternative route for nucleic acid delivery using a biomanufacturable, biodegradable, biocompatible, and highly tunable vehicle capable of targeting cells via engagement with overexpressed cell surface receptors.


Subject(s)
Elastin , Nanoparticles , Urinary Bladder Neoplasms , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/pathology , Humans , Elastin/chemistry , Mice , Animals , Nanoparticles/chemistry , Cell Line, Tumor , ErbB Receptors/metabolism , ErbB Receptors/genetics , Peptides/chemistry , Nucleic Acids/chemistry , Nucleic Acids/administration & dosage , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/chemistry , Elastin-Like Polypeptides
5.
Protein Expr Purif ; 224: 106578, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39153561

ABSTRACT

Current biological research requires simple protein bioseparation methods capable of purifying target proteins in a single step with high yields and purities. Conventional affinity tag-based approaches require specific affinity resins and expensive proteolytic enzymes for tag removal. Purification strategies based on self-cleaving aggregating tags have been previously developed to address these problems. However, these methods often utilize C-terminal cleaving contiguous inteins which suffer from premature cleavage, resulting in significant product loss during protein expression. In this work, we evaluate two novel mutants of the Mtu RecA ΔI-CM mini-intein obtained through yeast surface display for improved protein purification. When used with the elastin-like-polypeptide (ELP) precipitation tag, the novel mutants - ΔI-12 and ΔI-29 resulted in significantly higher precursor content, product purity and process yield compared to the original Mtu RecA ΔI-CM mini-intein. Product purities ranging from 68 % to 94 % were obtained in a single step for three model proteins - green fluorescent protein (GFP), maltose binding protein (MBP) and beta-galactosidase (beta-gal). Further, high cleaving efficiency was achieved after 5 h under most conditions. Overall, we have developed improved self-cleaving precipitation tags which can be used for purifying a wide range of proteins cheaply at laboratory scale.


Subject(s)
Inteins , Maltose-Binding Proteins , Rec A Recombinases , beta-Galactosidase , Inteins/genetics , beta-Galactosidase/genetics , beta-Galactosidase/chemistry , beta-Galactosidase/isolation & purification , beta-Galactosidase/metabolism , Maltose-Binding Proteins/genetics , Maltose-Binding Proteins/chemistry , Maltose-Binding Proteins/metabolism , Rec A Recombinases/genetics , Rec A Recombinases/chemistry , Rec A Recombinases/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Elastin/chemistry , Elastin/genetics , Elastin/isolation & purification , Chemical Precipitation , Escherichia coli/genetics , Escherichia coli/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/chemistry
6.
Sci Rep ; 14(1): 20223, 2024 08 30.
Article in English | MEDLINE | ID: mdl-39215050

ABSTRACT

Large bone defects are a significant health problem today with various origins, including extensive trauma, tumours, or congenital musculoskeletal disorders. Tissue engineering, and in particular bone tissue engineering, aims to respond to this demand. As such, we propose a specific model based on Elastin-Like Recombinamers-based click-chemistry hydrogels given their high biocompatibility and their potent on bone regeneration effect conferred by different bioactive sequences. In this work we demonstrate, using biochemistry, histology, histomorphometry and imaging techniques, the biocompatibility of our matrix and its potent effect on bone regeneration in a model of bone parietal lesion in female New Zealand rabbits.


Subject(s)
Biocompatible Materials , Bone Regeneration , Elastin , Hydrogels , Tissue Engineering , Animals , Female , Rabbits , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Bone Regeneration/drug effects , Click Chemistry/methods , Elastin/chemistry , Hydrogels/chemistry , Hydrogels/pharmacology , Tissue Engineering/methods , Tissue Scaffolds/chemistry
7.
Biomed Pharmacother ; 177: 117051, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38959608

ABSTRACT

Due to the limitations of the current skin wound treatments, it is highly valuable to have a wound healing formulation that mimics the extracellular matrix (ECM) and mechanical properties of natural skin tissue. Here, a novel biomimetic hydrogel formulation has been developed based on a mixture of Agarose-Collagen Type I (AC) combined with skin ECM-related components: Dermatan sulfate (DS), Hyaluronic acid (HA), and Elastin (EL) for its application in skin tissue engineering (TE). Different formulations were designed by combining AC hydrogels with DS, HA, and EL. Cell viability, hemocompatibility, physicochemical, mechanical, and wound healing properties were investigated. Finally, a bilayered hydrogel loaded with fibroblasts and mesenchymal stromal cells was developed using the Ag-Col I-DS-HA-EL (ACDHE) formulation. The ACDHE hydrogel displayed the best in vitro results and acceptable physicochemical properties. Also, it behaved mechanically close to human native skin and exhibited good cytocompatibility. Environmental scanning electron microscopy (ESEM) analysis revealed a porous microstructure that allows the maintenance of cell growth and ECM-like structure production. These findings demonstrate the potential of the ACDHE hydrogel formulation for applications such as an injectable hydrogel or a bioink to create cell-laden structures for skin TE.


Subject(s)
Biomimetic Materials , Hydrogels , Tissue Engineering , Hydrogels/chemistry , Humans , Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Tissue Engineering/methods , Cell Survival/drug effects , Mesenchymal Stem Cells/drug effects , Hyaluronic Acid/chemistry , Hyaluronic Acid/pharmacology , Wound Healing/drug effects , Collagen Type I/metabolism , Skin/drug effects , Skin/metabolism , Dermatan Sulfate/chemistry , Dermatan Sulfate/pharmacology , Fibroblasts/drug effects , Elastin/chemistry , Extracellular Matrix/metabolism , Biomimetics/methods , Sepharose/chemistry , Dermis/drug effects , Dermis/metabolism , Dermis/cytology , Animals
8.
Biomacromolecules ; 25(8): 4898-4904, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-38980747

ABSTRACT

Elastin-like polypeptides (ELPs) are a promising material platform for engineering stimuli-responsive biomaterials, as ELPs undergo phase separation above a tunable transition temperature. ELPs with phase behavior that is isothermally regulated by biological stimuli remain attractive for applications in biological systems. Herein, we report protease-driven phase separation of ELPs. Protease-responsive "cleavable" ELPs comprise a hydrophobic ELP block connected to a hydrophilic ELP block by a protease cleavage site linker. The hydrophilic ELP block acts as a solubility tag for the hydrophobic ELP block, creating a temperature window in which the cleavable ELP reactant is soluble and the proteolytically generated hydrophobic ELP block is insoluble. Within this temperature window, isothermal, protease-driven phase separation occurs when a critical concentration of hydrophobic cleavage product accumulates. Furthermore, protease-driven phase separation is generalizable to four compatible protease-cleavable ELP pairings. This work presents exciting opportunities to regulate ELP phase behavior in biological systems using proteases.


Subject(s)
Elastin , Hydrophobic and Hydrophilic Interactions , Peptides , Elastin/chemistry , Elastin/isolation & purification , Peptides/chemistry , Peptide Hydrolases/chemistry , Peptide Hydrolases/metabolism , Phase Transition , Elastin-Like Polypeptides , Phase Separation
9.
J Mater Chem B ; 12(36): 8966-8976, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39045800

ABSTRACT

Protein and peptide materials have attracted great interest in recent years, especially for biological applications, in light of their possibility to easily encode bioactivity whilst maintaining cytocompatibility and biodegradability. Heterologous recombinant expression to produce antimicrobial peptides is increasingly considered a convenient alternative for the transition from conventional methods to more sustainable production systems. The human elastin-like polypeptide (HELP) has proven to be a valuable fusion carrier, and due to its cutting-edge properties, biomimetic materials with antimicrobial capacity have been successfully developed. In this work, we have taken advantage of this platform to produce a difficult-to-synthesise sequence as that of the human ß-defensin 1 (hBD1), an amphipathic cationic peptide with structural folding constraints relevant to its bioactivity. In the design of the gene, highly specific endoproteinases recognition sites were introduced to release the active forms of hBD1. After the expression and purification of the new fusion construct, its biological activity was evaluated. It was found that both the fusion biopolymer and the released active forms can inhibit the growth of Escherichia coli in redox environments. Remarkably, 2D and 3D materials derived from the biopolymer showed a strong cell adhesion-promoting activity. These results suggest that HELP represents a multitasking platform that not only facilitates the production of bioactive domains and derived materials but could also pave the way for the development of new approaches to study biological interactions at the molecular level.


Subject(s)
Cell Adhesion , Elastin , Escherichia coli , Humans , Elastin/chemistry , Elastin/pharmacology , Escherichia coli/drug effects , Cell Adhesion/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Antimicrobial Peptides/chemistry , Antimicrobial Peptides/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Microbial Sensitivity Tests , Peptides/chemistry , Peptides/pharmacology , Elastin-Like Polypeptides
10.
Sci Rep ; 14(1): 15095, 2024 07 02.
Article in English | MEDLINE | ID: mdl-38956125

ABSTRACT

Nanogels offer hope for precise drug delivery, while addressing drug delivery hurdles is vital for effective prostate cancer (PCa) management. We developed an injectable elastin nanogels (ENG) for efficient drug delivery system to overcome castration-resistant prostate cancer (CRPC) by delivering Decursin, a small molecule inhibitor that blocks Wnt/ßcatenin pathways for PCa. The ENG exhibited favourable characteristics such as biocompatibility, flexibility, and low toxicity. In this study, size, shape, surface charge, chemical composition, thermal stability, and other properties of ENG were used to confirm the successful synthesis and incorporation of Decursin (DEC) into elastin nanogels (ENG) for prostate cancer therapy. In vitro studies demonstrated sustained release of DEC from the ENG over 120 h, with a pH-dependent release pattern. DU145 cell line induces moderate cytotoxicity of DEC-ENG indicates that nanomedicine has an impact on cell viability and helps strike a balance between therapeutics efficacy and safety while the EPR effect enables targeted drug delivery to prostate tumor sites compared to free DEC. Morphological analysis further supported the effectiveness of DEC-ENG in inducing cell death. Overall, these findings highlight the promising role of ENG-encapsulated decursin as a targeted drug delivery system for CRPC.


Subject(s)
Elastin , Nanogels , Prostatic Neoplasms, Castration-Resistant , Male , Elastin/chemistry , Humans , Cell Line, Tumor , Nanogels/chemistry , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/pathology , Prostatic Neoplasms, Castration-Resistant/metabolism , Drug Delivery Systems , Cell Survival/drug effects , Drug Liberation , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/administration & dosage , Benzopyrans , Butyrates
11.
J Phys Chem B ; 128(23): 5756-5765, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38830627

ABSTRACT

Elastin-like polymers are a class of stimuli-responsive protein polymers that hold immense promise in applications such as drug delivery, hydrogels, and biosensors. Yet, understanding the intricate interplay of factors influencing their stimuli-responsive behavior remains a challenging frontier. Using temperature-controlled dynamic light scattering and zeta potential measurements, we investigate the interactions between buffer, pH, salt, water, and protein using an elastin-like polymer containing ionizable lysine residues. We observed the elevation of transition temperature in the presence of the common buffering agent HEPES at low concentrations, suggesting a "salting-in" effect of HEPES as a cosolute through weak association with the protein. Our findings motivate a more comprehensive investigation of the influence of buffer and other cosolute molecules on elastin-like polymer behavior.


Subject(s)
Dynamic Light Scattering , Elastin , Elastin/chemistry , Hydrogen-Ion Concentration , Phase Transition , Water/chemistry , Polymers/chemistry
12.
ACS Appl Bio Mater ; 7(7): 4573-4579, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38926913

ABSTRACT

There is an emerging strong demand for smart environmentally responsive protein-based biomaterials with improved adhesion properties, especially underwater adhesion for potential environmental and medical applications. Based on the fusion of elastin-like polypeptides (ELPs), SpyCatcher and SpyTag modules, biosynthetic barnacle-derived protein was genetically engineered and self-assembled with an enhanced adhesion ability and temperature response. The water resistance ability of the synthetic protein biopolymer with a network structure increased to 98.8 from 58.5% of the original Cp19k, and the nonaqueous adhesion strength enhanced to 1.26 from 0.68 MPa of Cp19k. The biopolymer showed an improved adhesion ability toward hydrophilic and hydrophobic surfaces as well as diatomite powders. The combination of functional module ELPs and SpyTag/SpyCatcher could endow the biosynthetic protein with temperature response, an insoluble form above 42 °C and a soluble form at 4 °C. The combinational advantages including temperature response and adhesion performance make the self-assembled protein an excellent candidate in surgical adhesion, underwater repair, and surface modification of various coatings. Distinct from the traditional approach of utilizing solely ELPs, the integration of short ELPs with Spy partners exhibited a synergistic enhancement in the temperature response. The synergistic effects of two functional modules provide a technical method and insight for designing smart self-assembled protein-based biopolymers.


Subject(s)
Biocompatible Materials , Materials Testing , Temperature , Thoracica , Biocompatible Materials/chemistry , Animals , Surface Properties , Particle Size , Elastin/chemistry , Hydrophobic and Hydrophilic Interactions
13.
Protein Expr Purif ; 222: 106521, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38852714

ABSTRACT

Plants are often seen as a potent tool in the recombinant protein production industry. However, unlike bacterial expression, it is not a popular method due to the low yield and difficulty of protein extraction and purification. Therefore, developing a new high efficient and easy to purify platform is crucial. One of the best approaches to make extraction easier is to utilize the Extensin Signal peptide (EXT) to translocate the recombinant protein to the outside of the cell, along with incorporating an Elastin-like polypeptide tag (ELP) to enhance purification and accumulation rates. In this research, we transiently expressed Shigella dysenteriae's IpaDSTxB fused to both NtEXT and ELP in both Nicotiana tabacum and Medicago sativa. Our results demonstrated that N. tabacum, with an average yield of 6.39 ng/µg TSP, outperforms M. sativa, which had an average yield of 3.58 ng/µg TSP. On the other hand, analyzing NtEXT signal peptide indicated that merging EXT to the constructs facilitates translocation of IpaDSTxB to the apoplast by 78.4% and 65.9% in N. tabacum and M. sativa, respectively. Conversely, the mean level for constructs without EXT was below 25% for both plants. Furthermore, investigation into the orientation of ELP showed that merging it to the C-terminal of IpaDSTxB leads to a higher accumulation rate in both N. tabacum and M. sativa by 1.39 and 1.28 times, respectively. It also facilitates purification rate by over 70% in comparison to 20% of the 6His tag. The results show a highly efficient and easy to purify platform for the expression of heterologous proteins in plant.


Subject(s)
Bacterial Proteins , Elastin , Nicotiana , Protein Sorting Signals , Recombinant Fusion Proteins , Shigella dysenteriae , Nicotiana/genetics , Nicotiana/metabolism , Protein Sorting Signals/genetics , Bacterial Proteins/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/isolation & purification , Bacterial Proteins/biosynthesis , Bacterial Proteins/metabolism , Elastin/genetics , Elastin/chemistry , Elastin/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/metabolism , Shigella dysenteriae/genetics , Medicago sativa/genetics , Medicago sativa/metabolism , Medicago sativa/chemistry , Medicago sativa/microbiology , Gene Expression , Plant Proteins/genetics , Plant Proteins/biosynthesis , Plant Proteins/isolation & purification , Plant Proteins/chemistry , Plant Proteins/metabolism , Glycoproteins/genetics , Glycoproteins/chemistry , Glycoproteins/isolation & purification , Glycoproteins/biosynthesis , Glycoproteins/metabolism , Elastin-Like Polypeptides
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124692, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-38908361

ABSTRACT

There is the rapid growth in application of Brillouin scattering spectroscopy to biomedical objects in order to characterize their mechanoelastic properties in this way. However, the possibilities and limitations of the method when applied to tissues have not yet been clarified. Here, applicability of Brillouin spectroscopy for testing the elastic response of medically relevant tissues of bovine jugular vein and pericardium was considered. Parameters of the Brillouin peak were studied for samples untreated, diepoxide-fixed, and preserved after treatment in alcohol solutions. It was found that diepoxide cross-linking resulted to a slight tendency to increase the Brillouin position for hydrated tissues. The variations in the position and width of the Brillouin peaks, associated with local fluctuations in water concentration, were reduced after diepoxide treatment in the case of the pericardium, but not in the case of the vein wall. To obtain more information about the elastic response of the protein scaffold without the participation of water, dried samples were also studied. Brillouin spectra of the dried pericardium and vein wall revealed a significant increase in the Brillouin peak position (elastic modulus) after conservation in alcohol. In the case of the vein wall, this effect was found for both collagen and elastin-related peaks, which were identified in the Brillouin spectrum. This result corresponds to a denser packing of fibrous proteins after preservation in alcohol solutions. The ability of Brillouin spectroscopy to independently characterize the effect of treatment on the instantaneous elastic modulus of various tissue components is also attractive for its application in the development of new materials for bioimplants. A comparison of the Brillouin longitudinal and Young's elastic moduli determined for the hydrated samples of the vein and pericardium showed that there is no clear correspondence between these material parameters. The usefulness of using both experimental methods to obtain new information about the elastic response of the material is discussed.


Subject(s)
Jugular Veins , Pericardium , Animals , Cattle , Pericardium/chemistry , Spectrum Analysis/methods , Elastin/analysis , Elastin/chemistry , Elastic Modulus , Collagen/analysis , Collagen/chemistry
15.
Int J Biol Macromol ; 274(Pt 1): 133267, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38906359

ABSTRACT

While it is known that calcium phosphate (CaP) minerals deposit in elastin-rich medial layers of arteries during medial calcification, their nucleation and growth sites are still debated. Neutral carbonyl groups and carboxylate groups are possible candidates. Also, while it is known that elastin degradation leads to calcification, it is unclear whether this is due to formation of new carboxylate groups or elastin fragmentation. In this work, we disentangle effects of carboxylate groups and particle size on elastin calcification; in doing so, we shed light on CaP mineralization sites on elastin. We find carboxylate groups accelerate calcification only in early stages; they mainly function as Ca2+ ion chelation sites but not calcification sites. Their presence promotes formation (likely on Ca2+ ions adsorbed on nearby carbonyl groups) of CaP minerals with high calcium-to-phosphate ratio as intermediate phases. Larger elastin particles calcify slower but reach similar amounts of CaP minerals in late stages; they promote direct formation of hydroxyapatite and CaP minerals with low calcium-to-phosphate ratio as intermediate phases. This work provides new perspectives on how carboxylate groups and elastin particle size influence calcification; these parameters can be tuned to study the mechanism of medial calcification and design drugs to inhibit the process.


Subject(s)
Calcium Phosphates , Elastin , Particle Size , Elastin/metabolism , Elastin/chemistry , Calcium Phosphates/chemistry , Calcium Phosphates/metabolism , Animals , Carboxylic Acids/chemistry , Vascular Calcification/metabolism , Vascular Calcification/pathology , Calcium/metabolism , Durapatite/chemistry
16.
J Nanobiotechnology ; 22(1): 293, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38802812

ABSTRACT

BACKGROUND: The exogenous delivery of miRNA to mimic and restore miRNA-34a activity in various cancer models holds significant promise in cancer treatment. Nevertheless, its effectiveness is often impeded by challenges, including a short half-life, propensity for off-target accumulation, susceptibility to inactivation by blood-based enzymes, concerns regarding patient safety, and the substantial cost associated with scaling up. As a means of overcoming these barriers, we propose the development of miRNA-loaded Tat-A86 nanoparticles by virtue of Tat-A86's ability to shield the loaded agent from external environmental factors, reducing degradation and inactivation, while enhancing circulation time and targeted accumulation. RESULTS: Genetically engineered Tat-A86, featuring 16 copies of the interleukin-4 receptor (IL-4R)-binding peptide (AP1), Tat for tumor penetration, and an elastin-like polypeptide (ELP) for presenting target ligands and ensuring stability, served as the basis for this delivery system. Comparative groups, including Tat-E60 and A86, were employed to discern differences in binding and penetration. The designed ELP-based nanoparticle Tat-A86 effectively condensed miRNA, forming stable nanocomplexes under physiological conditions. The miRNA/Tat-A86 formulation bound specifically to tumor cells and facilitated stable miRNA delivery into them, effectively inhibiting tumor growth. The efficacy of miRNA/Tat-A86 was further evaluated using three-dimensional spheroids of lewis lung carcinoma (LLC) as in vitro model and LLC tumor-bearing mice as an in vivo model. It was found that miRNA/Tat-A86 facilitates effective cell killing by markedly improving miRNA penetration, leading to a substantial reduction in the size of LLC spheroids. Compared to other controls, Tat-A86 demonstrated superior efficacy in suppressing the growth of 3D cellular aggregates. Moreover, at equivalent doses, miRNA-34a delivered by Tat-A86 inhibited the growth of LLC cells in allograft mice. CONCLUSIONS: Overall, these studies demonstrate that Tat-A86 nanoparticles can deliver miRNA systemically, overcoming the basic hurdles impeding miRNA delivery by facilitating both miRNA uptake and stability, ultimately leading to improved therapeutic effects.


Subject(s)
Elastin , MicroRNAs , Nanoparticles , Peptides , Animals , MicroRNAs/genetics , Elastin/chemistry , Mice , Peptides/chemistry , Humans , Nanoparticles/chemistry , Cell Line, Tumor , Neoplasms/therapy , Neoplasms/drug therapy , Drug Carriers/chemistry , Female , Elastin-Like Polypeptides
17.
Biomacromolecules ; 25(5): 3011-3017, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38689515

ABSTRACT

Stabilization against the dilution-dependent disassembly of self-assembled nanoparticles is a requirement for in vivo application. Herein, we propose a simple and biocompatible cross-linking reaction for the stabilization of a series of nanoparticles formed by the self-assembly of amphiphilic HA-b-ELP block copolymers, through the alkylation of methionine residues from the ELP block with diglycidyl ether compounds. The core-cross-linked nanoparticles retain their colloidal properties, with a spherical core-shell morphology, while maintaining thermoresponsive behavior. As such, instead of a reversible disassembly when non-cross-linked, a reversible swelling of nanoparticles' core and increase of hydrodynamic diameter are observed with lowering of the temperature.


Subject(s)
Cross-Linking Reagents , Nanoparticles , Nanoparticles/chemistry , Cross-Linking Reagents/chemistry , Temperature , Polymers/chemistry , Elastin/chemistry , Particle Size
18.
ACS Appl Bio Mater ; 7(6): 3714-3720, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38748757

ABSTRACT

Biological water-responsive (WR) materials are abundant in nature, and they are used as mechanical actuators for seed dispersal by many plants such as wheat awns and pinecones. WR biomaterials are of interest for applications as high-energy actuators, which can be useful in soft robotics or for capturing energy from natural water evaporation. Recent work on WR silk proteins has shown that ß-sheet nanocrystalline domains with high stiffness correlate with the high WR actuation energy density, but the fundamental mechanisms to drive water responsiveness in proteins remain poorly understood. Here, we design, synthesize, and study protein block copolymers consisting of two α-helical domains derived from cartilage oligomeric matrix protein coiled-coil (C) flanking an elastin-like peptide domain (E), namely, CEC. We use these protein materials to create WR actuators with energy densities that outperform mammalian muscle. To elucidate the effect of structure on WR actuation, CEC was compared to a variant, CECL44A, in which a point mutation disrupts the α-helical structure of the C domain. Surprisingly, CECL44A outperformed CEC, showing higher energy density and less susceptibility to degradation after repeated cycling. We show that CECL44A exhibits a higher degree of intermolecular interactions and is stiffer than CEC at high relative humidity (RH), allowing for less energy dissipation during water responsiveness. These results suggest that strong intermolecular interactions and the resulting, relatively steady protein structure are important for water responsiveness.


Subject(s)
Biocompatible Materials , Materials Testing , Water , Water/chemistry , Biocompatible Materials/chemistry , Polymers/chemistry , Particle Size , Cartilage Oligomeric Matrix Protein/chemistry , Cartilage Oligomeric Matrix Protein/metabolism , Elastin/chemistry , Elastin/metabolism
19.
Biomacromolecules ; 25(6): 3519-3531, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38742604

ABSTRACT

Elastic fibers provide critical elasticity to the arteries, lungs, and other organs. Elastic fiber assembly is a process where soluble tropoelastin is coacervated into liquid droplets, cross-linked, and deposited onto and into microfibrils. While much progress has been made in understanding the biology of this process, questions remain regarding the timing of interactions during assembly. Furthermore, it is unclear to what extent fibrous templates are needed to guide coacervate droplets into the correct architecture. The organization and shaping of coacervate droplets onto a fiber template have never been previously modeled or employed as a strategy for shaping elastin fiber materials. Using an in vitro system consisting of elastin-like polypeptides (ELPs), genipin cross-linker, electrospun polylactic-co-glycolic acid (PLGA) fibers, and tannic acid surface coatings for fibers, we explored ELP coacervation, cross-linking, and deposition onto fiber templates. We demonstrate that integration of coacervate droplets into a fibrous template is primarily influenced by two factors: (1) the balance of coacervation and cross-linking and (2) the surface energy of the fiber templates. The success of this integration affects the mechanical properties of the final fiber network. Our resulting membrane materials exhibit highly tunable morphologies and a range of elastic moduli (0.8-1.6 MPa) comparable to native elastic fibers.


Subject(s)
Elastin , Polylactic Acid-Polyglycolic Acid Copolymer , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Elastin/chemistry , Lactic Acid/chemistry , Polyglycolic Acid/chemistry , Iridoids/chemistry , Tropoelastin/chemistry , Cross-Linking Reagents/chemistry , Tannins/chemistry , Peptides/chemistry , Elasticity
20.
Colloids Surf B Biointerfaces ; 240: 113988, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38810467

ABSTRACT

Confronted with the profound threat of cardiovascular diseases to health, vascular tissue engineering presents potential beyond the limitations of autologous and allogeneic grafts, offering a promising solution. This study undertakes an initial exploration into the impact of a natural active protein, elastin, on vascular cell behavior, by incorporating with polycaprolactone to prepare fibrous tissue engineering scaffold. The results reveal that elastin serves to foster endothelial cell adhesion and proliferation, suppress smooth muscle cell proliferation, and induce macrophage polarization. Furthermore, the incorporation of elastin contributes to heightened scaffold strength, compliance, and elongation, concomitantly lowering the elastic modulus. Subsequently, a bilayer oriented polycaprolactone (PCL) scaffold infused with elastin is proposed. This design draws inspiration from the cellular arrangement of native blood vessels, leveraging oriented fibers to guide cell orientation. The resulting fiber scaffold exhibits commendable mechanical properties and cell infiltration capacity, imparting valuable insights for the rapid endothelialization of vascular scaffolds.


Subject(s)
Cell Adhesion , Cell Proliferation , Nanofibers , Polyesters , Tissue Engineering , Tissue Scaffolds , Tissue Scaffolds/chemistry , Nanofibers/chemistry , Polyesters/chemistry , Polyesters/pharmacology , Cell Proliferation/drug effects , Humans , Cell Adhesion/drug effects , Animals , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/cytology , Elastin/chemistry , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/cytology , Mice , Cells, Cultured , Endothelial Cells/drug effects , Endothelial Cells/cytology
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