Technical Blog
John GarnerJohn Garner, General Manager

A blog dedicated to answering technical questions in an open format relating to products from PolySciTech, a division of Akina, Inc.


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PLLA-Fluorescein from PolySciTech used in development of contraceptive microneedle

Thursday, May 26, 2022, 1:58 PM ET

One method for drug-delivery is to utilize microneedles, patches comprised of very small biodegradable needles too small to see. These can be used for long-lasting delivery of agents including contraceptives. Recently, researchers at Georgia Institute of Technology, University of Michigan, and Wuhan University (China) used PLLA-Fluorescein (AV004) from PolySciTech (www.polyscitech.com) to create fluorescently strained microparticles for delivery of contraceptive hormone, levonorgestrel. This research holds promise to provide for extended contraceptive action in a less invasive manner than existing products such as IUDs. Read more: Li, Wei, Jonathan Yuxuan Chen, Richard N. Terry, Jie Tang, Andrey Romanyuk, Steven P. Schwendeman, and Mark R. Prausnitz. "Core-shell microneedle patch for six-month controlled-release contraceptive delivery." Journal of Controlled Release 347 (2022): 489-499. https://www.sciencedirect.com/science/article/pii/S0168365922002656

“Highlights: Developed a novel core-shell microneedle where the shell is a rate-controlling membrane to achieve zero-order drug release. Constructed the core-shell structure by sequential casting into a single mold by solvent engineering. Achieved six-month controlled-release contraceptive delivery in vitro. Abstract: There is a tremendous need for simple-to-administer, long-acting contraception, which can increase access to improved family planning. Microneedle (MN) patches enable simple self-administration and have previously been formulated for 1–2 months-controlled release of contraceptive hormone using monolithic polymer/drug MN designs having first-order release kinetics. To achieve zero-order release, we developed a novel core-shell MN patch where the shell acts as a rate-controlling membrane to delay release of a contraceptive hormone, levonorgestrel (LNG), for 6 months. In this approach, LNG was encapsulated in a poly(lactide-co-glycolide) (PLGA) core surrounded by a poly(l-lactide) (PLLA) shell and a poly(D,L-lactide) (PLA) cap that were fabricated by sequential casting into a MN mold. Upon application to skin, the core-shell MNs utilized an effervescent interface to separate from the patch backing within 1 min. The core-shell design limited the initial 24 h burst release of LNG to 5.8 ± 0.5% and achieved roughly zero-order LNG release for 6.2 ± 0.1 months in vitro. A monolithic MN patch formulated with the same LNG and PLGA core, but without the rate-controlling PLLA shell and PLA cap had a larger LNG burst release of 22.6 ± 2.0% and achieved LNG release for just 2.1 ± 0.2 months. This study provides the first core-shell MN patch for controlled months-long drug release and supports the development of long-acting contraception using a simple-to-administer, twice-per-year MN patch.”

PLCL from PolySciTech used in development of sprayable tissue adhesive for surgical applications

Wednesday, May 18, 2022, 3:51 PM ET

After surgery it is not uncommon for various internal tissues to heal together inappropriately, i.e. certain layers of tissue will heal to one another rather than as discrete layers. This problem can lead to adhesions, fibrous bridges that connect tissue surfaces together and is usually affiliated with an inflammatory response post-surgery. These adhesions can lead to severe pain as well as bowel obstruction and infertility, depending on their location. Recently, researchers at University of Maryland, Massachusetts Institute of Technology, and Children’s National Medical Center utilized various PLCL polymers (cat# AP212, AP178, AP179, and AP151) from PolySciTech (www.polyscitech.com) to create a spray-on layer of biodegradable polymer that reduces the formation of these adhesions between tissues. This research holds promise to reduce this common post-surgical complication. Read more: Erdi, Metecan, Selim Rozyyev, Manogna Balabhadrapatruni, Michele S. Saruwatari, John L. Daristotle, Omar B. Ayyub, Anthony D. Sandler, and Peter Kofinas. "Sprayable Tissue Adhesive with Biodegradation Tuned for Prevention of Post‐Operative Abdominal Adhesions." Bioengineering & Translational Medicine: e10335. https://aiche.onlinelibrary.wiley.com/doi/abs/10.1002/btm2.10335

“Abstract: Adhesions are dense, fibrous bridges that adjoin tissue surfaces due to uncontrolled inflammation following post-operative mesothelial injury. A widely used adhesion barrier material in Seprafilm often fails to prevent transverse scar tissue deposition because of its poor mechanical properties, rapid degradation profile, and difficulty in precise application. Solution blow spinning (SBS), a polymer fiber deposition technique, allows for the placement of in-situ tissue-conforming and tissue-adherent scaffolds with exceptional mechanical properties. While biodegradable polymers such as poly(lactic-co-glycolic acid) (PLGA) have desirable strength, they exhibit bulk biodegradation rates and inflammatory profiles that limit their use as adhesion barriers and result in poor tissue adhesion. Here, viscoelastic poly(lactide-co-caprolactone) (PLCL) is used for its pertinent biodegradation mechanism. Because it degrades via surface erosion, spray deposited PLCL fibers can dissolve new connections formed by inflamed tissue, allowing them to function as an effective, durable, and easy to apply adhesion barrier. Degradation kinetics are tuned to match adhesion formation through design of PLCL blends comprised of highly adhesive “low” molecular weight (LMW) constituents in a mechanically robust “high” molecular weight (HMW) matrix. In-vitro studies demonstrate that blending LMW PLCL (30% w/v) with HMW PLCL (70% w/v) yields an anti-fibrotic yet tissue-adhesive polymer sealant with a 14-day erosion rate countering adhesion formation. PLCL blends additionally exhibit improved wet tissue adhesion strength (~10 kPa) over a 14-day period versus previously explored biodegradable polymer compositions, such as PLGA. In a mouse cecal ligation model, select PLCL blends significantly reduce abdominal adhesions severity versus no treatment and Seprafilm treated controls.”

PLCL from PolySciTech used in development of burn wound healing scaffold of cells and polymer mesh.

Tuesday, May 3, 2022, 12:06 PM ET

Deep tissue burn wounds heal poorly on their own due to extensive cellular damage and lost flesh. Recently, researchers at Georgetown University, University of Maryland, Children’s National Medical Center, Massachusetts Institute of Technology, and MedStar Washington Hospital Center used PLCL (Cat# AP179) from PolySciTech (www.polyscitech.com) to create a blow-spun polymer formulation which can support a cell suspension. Applying this over a burn wound can aid in regrowth and repair of the damaged tissue. This research holds promise to assist in healing of traumatic burn wounds. (Screen-shot Video available here: https://ars.els-cdn.com/content/image/1-s2.0-S0305417922000122-mmc28.mp4) Read more: Carney, Bonnie C., Mary A. Oliver, Metecan Erdi, Liam D. Kirkpatrick, Stephen P. Tranchina, Selim Rozyyev, John W. Keyloun et al. "Evaluation of Healing Outcomes Combining A Novel Polymer Formulation with Autologous Skin Cell Suspension to Treat Deep Partial and Full Thickness Wounds in a Porcine Model; A Pilot Study." Burns (2022). https://www.sciencedirect.com/science/article/pii/S0305417922000122

“Highlights: Autologous skin cell suspensions sprayed onto wounds can be primarily dressed with a solution-blow spun polymer formulation. Polymer is not cytotoxic to cells and wound beds. Wound closure and scar levels are similar to controls, but usability and sealing of wounds is preferred in polymer-dressed wounds. Abstract: Autologous skin cell suspensions (ASCS) can treat burns of varying depths with the advantage of reduced donor site wound burden. The current standard primary dressing for ASCS is a nonabsorbant, non-adherent, perforated film (control) which has limited conformability over heterogeneous wound beds and allows for run-off of the ASCS. To address these concerns, a novel spray-on polymer formulation was tested as a potential primary dressing in porcine deep partial thickness (DPT) and full thickness (FT) wounds. It was hypothesized that the polymer would perform as well as control dressing when evaluating wound healing and scarring. DPT or FT wounds were treated with either a spray-on poly(lactic-co-glycolic acid) (PLGA) and poly(lactide-co-caprolactone) (PLCL) formulation or control ASCS dressings. Throughout the experimental time course (to day 50), we found no significant differences between polymer and control wounds in % re-epithelialization, graft-loss, epidermal or dermal thickness, or % dermal cellularity in either model. Pigmentation, erythema, elasticity, and trans-epidermal water loss (TEWL), were not significantly altered between the treatment groups, but differences between healing wounds/scars and un-injured skin were observed. No cytotoxic effect was observed in ASCS incubated with the PLGA and PLCL polymers. These data suggest that the novel spray-on polymer is a viable option as a primary dressing, with improved ease of application and conformation to irregular wounds. Polymer formulation and application technique should be a subject of future research.”

PLGA from PolySciTech used in development of microparticle-based treatment of osteoarthritis

Tuesday, May 3, 2022, 11:58 AM ET

Osteoarthritis is a degenerative disease affecting the cartilage in joints leading to significant damage, pain, and loss of functionality. Non-surgical treatment options are highly limited to symptomatic relief. Drug delivery to cartilage and bone tissues in a systemic sense is complicated by relatively poor blood flow in these area. Recently, researchers at Indian Institute of Science and MS Ramaiah Medical College (India) used PLGAs (cat# AP041, AP089, AP036) from PolySciTech (www.polyscitech.com) to create a series of microparticles to release rapamycin locally. This drug acted to prevent senescence and increase cartilage production. This research holds promise to improve therapies against arthritis. Read more: Dhanabalan, Kaamini M., Ameya A. Dravid, Smriti Agarwal, Ramanath K. Sharath, Ashok Kumar Padmanabhan, and Rachit Agarwal. "Intra‐articular Injection of Rapamycin Microparticles Prevent Senescence and Effectively Treat Osteoarthritis." Bioengineering & Translational Medicine: e10298. https://aiche.onlinelibrary.wiley.com/doi/abs/10.1002/btm2.10298

“Trauma to the knee joint is associated with significant cartilage degeneration and erosion of subchondral bone, which eventually leads to osteoarthritis (OA), resulting in substantial morbidity and healthcare burden. With no disease-modifying drugs in clinics, the current standard of care focuses on symptomatic relief and viscosupplementation. Modulation of autophagy and targeting senescence pathways are emerging as potential treatment strategies. Rapamycin has shown promise in OA disease amelioration by autophagy upregulation, yet its clinical use is hindered by difficulties in achieving therapeutic concentrations, necessitating multiple weekly injections. Rapamycin-loaded in poly (lactic-co-glycolic acid) microparticles (RMPs) induced autophagy, prevented senescence, and sustained sulphated glycosaminoglycans(sGAG) production in primary human articular chondrocytes from OA patients. RMPs were potent, nontoxic, and exhibited high retention time (up to 35 days) in mice joints. Intra-articular delivery of RMPs effectively mitigated cartilage damage and inflammation in surgery-induced OA when administered as a prophylactic or therapeutic regimen. Together, the study demonstrates the feasibility of using RMPs as a potential clinically translatable therapy to prevent the progression of post-traumatic osteoarthritis.”

PLGA from PolySciTech used in development of cardiovascular targeting nanoparticle for heart therapies

Tuesday, April 19, 2022, 2:45 PM ET

Notch, a specific signaling protein, is essential for proper development of the heart as this regulates signals between the endocardium and myocardium for chamber development. The ability to deliver genetic factors to correct issues with this signal formation can be used to aid in specific cardiovascular disease or formation issues. Recently, researchers at University of Texas at Arlington, University of North Texas, and University of California, Irvine used PLGA (cat# AP154) from PolySciTech (www.polyscitech.com) to create nanoparticles loaded with Notch plasmid to test the delivery of this gene to cells. They also tested the particles for any prevelant environmental danger which, owing to the biocompatible and biodegradable nature of PLGA, were minimal. Read more: Messerschmidt, V., Uday Chintapula, Fabrizio Bonetesta, Samantha Laboy-Segarra, Amir Naderi, K. Nguyen, Hung Cao, Edward Mager, and Juhyun Lee. "In vivo Evaluation of Non-viral NICD Plasmid-Loaded PLGA Nanoparticles in Developing Zebrafish to Improve Cardiac Functions." Frontiers in physiology 13 (2022). https://europepmc.org/articles/pmc8906778/bin/data_sheet_1.pdf

“Abstract: In the era of the advanced nanomaterials, use of nanoparticles has been highlighted in biomedical research. However, the demonstration of DNA plasmid delivery with nanoparticles for in vivo gene delivery experiments must be carefully tested due to many possible issues, including toxicity. The purpose of the current study was to deliver a Notch Intracellular Domain (NICD)-encoded plasmid via poly(lactic-co-glycolic acid) (PLGA) nanoparticles and to investigate the toxic environmental side effects for an in vivo experiment. In addition, we demonstrated the target delivery to the endothelium, including the endocardial layer, which is challenging to manipulate gene expression for cardiac functions due to the beating heart and rapid blood pumping. For this study, we used a zebrafish animal model and exposed it to nanoparticles at varying concentrations to observe for specific malformations over time for toxic effects of PLGA nanoparticles as a delivery vehicle. Our nanoparticles caused significantly less malformations than the positive control, ZnO nanoparticles. Additionally, the NICD plasmid was successfully delivered by PLGA nanoparticles and significantly increased Notch signaling related genes. Furthermore, our image based deep-learning analysis approach evaluated that the antibody conjugated nanoparticles were successfully bound to the endocardium to overexpress Notch related genes and improve cardiac function such as ejection fraction, fractional shortening, and cardiac output. This research demonstrates that PLGA nanoparticle-mediated target delivery to upregulate Notch related genes which can be a potential therapeutic approach with minimum toxic effects. Keywords: PLGA nanoparticles, toxicity, non-viral transfection, zebrafish, gene delivery, Notch signaling”

PLGA and PEG-PLGA from PolySciTech used in development of CRISPR technique for gene editing in vascular system

Tuesday, April 19, 2022, 2:44 PM ET

The ability to deliver genetic material and make edits to existing cells holds great promise for treating a wide variety of diseases. Recently, researchers at the Lurie Hospital of Chicago and Northwestern University used PLGA (Cat# AP121) and PEG-PLGA (Cat# AK026) from PolySciTech (www.polyscitech.com) to create nanoparticles for delivery of plasmid DNA to vascular components. This research holds promise to improve treatment against cardiovascular diseases by modifying genes to correct disease states. Read more: Zhang, Xianming, Hua Jin, Xiaojia Huang, Birendra Chaurasiya, Daoyin Dong, Thomas P. Shanley, and You-Yang Zhao. "Robust genome editing in adult vascular endothelium by nanoparticle delivery of CRISPR-Cas9 plasmid DNA." Cell reports 38, no. 1 (2022): 110196. https://www.sciencedirect.com/science/article/pii/S2211124721017009

“Highlights: PPP i.v. exhibits excellent biodistribution without specific liver accumulation. PPP efficiently delivers plasmid DNA in vivo targeting vascular ECs. PPP delivery of CRISPR plasmid decreases 80% protein in cardiopulmonary vascular ECs. The system induces genome editing of two genes in ECs without limitation on plasmid size. Abstract: Vascular endothelium plays a crucial role in vascular homeostasis and tissue fluid balance. To target endothelium for robust genome editing, we developed poly(ethylene glycol) methyl ether-block-poly(lactide-co-glycolide) (PEG-b-PLGA) copolymer-based nanoparticle formulated with polyethyleneimine. A single i.v. administration of mixture of nanoparticles and plasmid DNA expressing Cas9 controlled by CDH5 promoter and guide RNA (U6 promoter) induced highly efficient genome editing in endothelial cells (ECs) of the vasculatures, including lung, heart, aorta, and peripheral vessels in adult mice. Western blotting and immunofluorescent staining demonstrated an ∼80% decrease of protein expression selectively in ECs, resulting in a phenotype similar to that of genetic knockout mice. Nanoparticle delivery of plasmid DNA could induce genome editing of two genes or genome editing and transgene expression in ECs simultaneously. Thus, nanoparticle delivery of plasmid DNA is a powerful tool to rapidly and efficiently alter expression of gene(s) in ECs for cardiovascular research and potential gene therapy. Keywords: CRISPR-Cas9 cardiovascular disease endothelial cell genome editing nanoparticle non-viral CRISPR delivery gene delivery gene therapy endothelium targeting lung diseases”

PLA-PEG from PolySciTech used in development of bronchial-targetting particles for cystic fibrosis therapy

Tuesday, April 12, 2022, 1:47 PM ET

Cystic fibrosis is the second most common lethal inherited disorder related to a specific mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The potential for gene-editing may provide a treatment for this incurable disase. Recently, researchers at Yale University used PEG-PLA (cat# AK054) from PolySciTech (www.polyscitech.com) to test the effect of nanoparticle decorations on bronchial uptake from an inhaled formulation. This research holds promise to improve treatments against cystic fibrosis in the future. Read more: Luks, Valerie L., Hanna Mandl, Jenna DiRito, Christina Barone, Mollie R. Freedman-Weiss, Adele S. Ricciardi, Gregory G. Tietjen, Marie E. Egan, W. Mark Saltzman, and David H. Stitelman. "Surface conjugation of antibodies improves nanoparticle uptake in bronchial epithelial cells." PloS one 17, no. 4 (2022): e0266218. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0266218

“Abstract: Background: Advances in Molecular Therapy have made gene editing through systemic or topical administration of reagents a feasible strategy to treat genetic diseases in a rational manner. Encapsulation of therapeutic agents in nanoparticles can improve intracellular delivery of therapeutic agents, provided that the nanoparticles are efficiently taken up within the target cells. In prior work we had established proof-of-principle that nanoparticles carrying gene editing reagents can mediate site-specific gene editing in fetal and adult animals in vivo that results in functional disease improvement in rodent models of β-thalassemia and cystic fibrosis. Modification of the surface of nanoparticles to include targeting molecules (e.g. antibodies) holds the promise of improving cellular uptake and specific cellular binding. Methods and findings: To improve particle uptake for diseases of the airway, like cystic fibrosis, our group tested the impact of nanoparticle surface modification with cell surface marker antibodies on uptake in human bronchial epithelial cells in vitro. Binding kinetics of antibodies (Podoplanin, Muc 1, Surfactant Protein C, and Intracellular Adhesion Molecule-1 (ICAM)) were determined to select appropriate antibodies for cellular targeting. The best target-specific antibody among those screened was ICAM antibody. Surface conjugation of nanoparticles with antibodies against ICAM improved cellular uptake in bronchial epithelial cells up to 24-fold. Conclusions: This is a first demonstration of improved nanoparticle uptake in epithelial cells using conjugation of target specific antibodies. Improved binding, uptake or specificity of particles delivered systemically or to the luminal surface of the airway would potentially improve efficacy, reduce the necessary dose and thus safety of administered therapeutic agents. Incremental improvement in the efficacy and safety of particle-based therapeutic strategies may allow genetic diseases such as cystic fibrosis to be cured on a fundamental genetic level before birth or shortly after birth.”

Thermogelling PLGA-PEG-PLGA from PolySciTech used in development of doxorubicin delivery system to prevent posterior capsule opacification

Tuesday, April 12, 2022, 1:46 PM ET

After surgical repairs made to the eye including cornea transplant or cataracts removal there are instances in which scar tissue grows along the ocular lense components leading to cloudiness or haze which reduces vision in the patient. Recently, researchers at Rowan University used thermogelling PLGA-PEG-PLGA (cat# AK097) from PolySciTech (www.polyscitech.com) to create a gel for controlled delivery of nucleic-acid nanocarriers of doxorubicin to prevent posterior capsule opacification (PCO). This research may assist in preserving sight after surgical repair. Read more: Osorno, Laura L., Robert J. Mosley, Patricia L. Poley, Jessica Bowers, Grzegorz Gorski, Jacquelyn Gerhart, Robert Getts, Mindy George-Weinstein, and Mark E. Byrne. "Sustained Release of Antibody-Conjugated DNA Nanocarriers from a Novel Injectable Hydrogel for Targeted Cell Depletion to Treat Cataract Posterior Capsule Opacification." Journal of Ocular Pharmacology and Therapeutics (2022). https://www.liebertpub.com/doi/abs/10.1089/jop.2021.0111

“Abstract: Purpose: To compare a novel, sustained release formulation and a bolus injection of a targeted nanocarrier for the ability to specifically deplete cells responsible for the development of posterior capsule opacification (PCO) in week-long, dynamic cell cultures. Methods: A novel, injectable, thermosensitive poly(D,L-lactic-co-glycolic acid)-b-poly(ethylene glycol)-b-poly(D,L-lactic-co-glycolic acid) (PLGA-PEG-PLGA) triblock copolymer hydrogel was engineered for the sustained release of targeted, nucleic acid nanocarriers loaded with cytotoxic doxorubicin (G8:3DNA:Dox). Human rhabdomyosarcoma (RD) cells were used due to their expression of brain-specific angiogenesis inhibitor 1 (BAI1), a specific marker for the myofibroblasts responsible for PCO. Under constant media flow, nanocarriers were injected into cell cultures as either a bolus or within the hydrogel. Cells were fixed and stained every other day for 7 days to compare targeted depletion of BAI1+ cells. Results: The formulation transitions to a gel at physiological temperatures, is optically clear, noncytotoxic, and can release G8:3DNA:Dox nanocarriers for up to 4 weeks. In RD cell cultures, G8:3DNA:Dox nanocarriers specifically eliminated BAI1+ cells. The bolus nanocarrier dose showed significantly reduced cell depletion overtime, while the sustained release of nanocarriers showed increased cell depletion over time. By day 7, <2% of BAI1+ cells were depleted by the bolus injection and 74.2% BAI1+ cells were targeted by the sustained release of nanocarriers. Conclusions: The sustained release of nanocarriers from the hydrogel allows for improved therapeutic delivery in a dynamic system. This method can offer a more effective and efficient method of prophylactically treating PCO after cataract surgery.”

PLGA from PolySciTech used in development of BMP-2 loaded particles for bone tissue engineering.

Tuesday, April 12, 2022, 1:45 PM ET

There are many situations in which bone can be damaged or lost including severe trauma (e.g. car accidents) or diseases such as cancer which necessitate removal of diseased portions. As bone tissue does not naturally regenerate damage which exceeds a certain volume or distance (i.e. a critical sized defect, bone can heal ‘breaks’ between adjacent pieces, but not large holes or amputations) this damage can leave patients with permanent, debilitating injuries. Recently, Gwangju Institute of Science and Technology and Korea Institute of Machinery and Materials (Korea) used PLGA (cat# AP018, AP036) from PolySciTech (www.polyscitech.com) to generate BMP-2 (a protein which induces bone healing) loaded particles and utilized these in a cell-scaffold to provide a structure to enable bone healing. This research holds promise to improve reconstructive surgery for repair of damage to bone tissue caused by trauma or surgery. Read more: Choe, Goeun, Mingyu Lee, Seulgi Oh, Ji Min Seok, Junghyun Kim, Seunghyun Im, Su A. Park, and Jae Young Lee. "Three-dimensional bioprinting of mesenchymal stem cells using an osteoinductive bioink containing alginate and BMP-2-loaded PLGA nanoparticles for bone tissue engineering." Biomaterials Advances (2022): 212789. https://www.sciencedirect.com/science/article/pii/S2772950822000668

“Highlights: We produced bioinks using alginate and poly(lactic-co-glycolic acid) nanoparticles. Composite bioink showed enhanced printability and yielded stable printed constructs. Bone morphogenetic protein-2-loaded nanoparticles achieved 2-week sustained release. The novel bioink significantly promoted osteogenesis of mesenchymal stem cells. Abstract: Hydrogels mimicking the physicochemical properties of the native extracellular matrix have attracted great attention as bioinks for three-dimensional (3D) bioprinting in tissue engineering applications. Alginate is a widely used bioink with beneficial properties of fast gelation and biocompatibility; however, bioprinting using alginate-based bioinks has several limitations, such as poor printability, structural instability, and limited biological activities. To address these issues, we formulated various bioinks using bone morphogenetic protein-2 (BMP-2)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles and alginate for mesenchymal stem cell (MSC) printing and induction of osteogenic differentiation. Incorporation of PLGA nanoparticles into alginate could enhance the mechanical properties and printability of the bioink. In particular, Alg/NPN30 (30 mg/mL PLGA nanoparticles and 3% w/v alginate) was most suitable for 3D printing with respect to printability and stability. BMP-2-loaded PLGA nanoparticles (NPBMP-2) displayed sustained in vitro release of BMP-2 for up to two weeks. Further in vitro studies indicated that bioinks composed of alginate and NPBMP-2 significantly induced osteogenesis of the MSCs compared with other controls, evidenced by enhanced calcium deposition, alkaline phosphatase activity, and gene expression of osteogenic markers. Our novel bioink consisting of widely used biocompatible components displays good printability, stability, and osteogenic inductivity, and holds strong potential for cell printing and bone tissue engineering applications. Graphical abstract: Our novel bioink, consisting of alginate and bone morphogenetic protein-2 (BMP-2)-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles, displays good printability, stability, and persistent osteogenic inductivity and will be beneficial for three-dimensional cell printing and bone tissue engineering applications.”

NIPAM based polymer from PolySciTech used in development of thermogel inkjet-printing technique

Monday, April 4, 2022, 1:08 PM ET

Advances in hydrogel and printing technology have enabled soft-printing techniques in which 3D structures are generated rapidly in desired format. Recently, researchers at Purdue University and Korea Institute of Industrial Technology used poly(n-isopropylacrylamide-co-acrylamide) (NIPAM-AM, cat# AO023) from PolySciTech (www.polyscitech.com) to investigate printing techniques and processes involved with print formation. This research holds promise to improve soft-printing techniques for a wide array of applications. Read more: Cheng, Cih, Yoon Jae Moon, Jun Young Hwang, George T-C. Chiu, and Bumsoo Han. "A scaling law of particle transport in inkjet-printed particle-laden polymeric drops." International Journal of Heat and Mass Transfer 191 (2022): 122840. https://www.sciencedirect.com/science/article/pii/S0017931022003222

“Highlights: A scaling law is proposed to predictively design inkjet printing processes of particle-laden hydrogels. A dimensionless similarity parameter is formulated and validated to predict particle distribution patterns in inkjet-printed hydrogel. Transport of particles in inkjet-printed hydrogels is determined by the balance of interstitial water flow and hindrance by the polymer matrix. Abstract: Hydrogels with embedded functional particulates are widely used to create soft materials with innovative functionalities. In order to advance these soft materials to functional devices and machines, critical technical challenges are the precise positioning of particulates within the hydrogels and the construction of the hydrogels into a complex geometry. Inkjet printing is a promising method for addressing these challenges and ultimately achieving hydrogels with voxelized functionalities, so-called digital hydrogels. However, the development of the inkjet printing process primarily relies on empirical optimization of its printing and curing protocol. In this study, a general scaling law is proposed to predict the transport of particulates within the hydrogel during inkjet printing. This scaling law is based on a hypothesis that water-matrix interaction during the curing of inkjet-printed particle-laden polymeric drops determines the intra-drop particle distribution. Based on the hypothesis, a dimensionless similarity parameter of the water-matrix interaction is proposed, determined by the hydrogel's water evaporation coefficient, particle size, and mechanical properties. The hypothesis was tested by correlating the intra-drop particle distribution to the similarity parameter. The results confirmed the scaling law capable of guiding ink formulation and printing and curing protocol. Keywords: Similarity Poroelasticity Thermally responsive polymer Particle distribution Digital hydrogel”

PEG-PLGA from PolySciTech used in evaluation of cancer in-vitro models.

Monday, April 4, 2022, 1:07 PM ET

To evaluate cancer therapies a realistic model must be utilized to determine the efficacy of the therapy preferably in-vitro or in animal model to prevent failed therapies from proceeding to clinical trials. Researchers at The University of Queensland used mPEG-PLGA (cat# AK026) from PolySciTech (www.polyscitech.com) to create nanoparticles to test a variety of biomimicking gels used as models for cancer behavior in-vitro. This research holds promise to improve testing methods for cancer therapies in the future. Read more: Cameron, Anna P., Bijun Zeng, Yun Liu, Haofei Wang, Mohammad Soheilmoghaddam, Justin Cooper-White, and Chun-Xia Zhao. "Biophysical properties of hydrogels for mimicking tumor extracellular matrix." Biomaterials Advances (2022): 212782. https://www.sciencedirect.com/science/article/pii/S2772950822000590

“Highlights: Evaluation of biophysical attributes of Matrigel, collagen gel and agarose gel. Characterization of complex modulus, loss tangent, permeability and pore size of hydrogels. A new and facile method for the characterization of hydrogel microstructures. A microfluidic approach for measuring hydrogel permeability. Abstract: The extracellular matrix (ECM) is an essential component of the tumor microenvironment. It plays a critical role in regulating cell-cell and cell-matrix interactions. However, there is lack of systematic and comparative studies on different widely-used ECM mimicking hydrogels and their properties, making the selection of suitable hydrogels for mimicking different in vivo conditions quite random. This study systematically evaluates the biophysical attributes of three widely used natural hydrogels (Matrigel, collagen gel and agarose gel) including complex modulus, loss tangent, diffusive permeability and pore size. A new and facile method was developed combining Critical Point Drying, Scanning Electron Microscopy imaging and a MATLAB image processing program (CSM method) for the characterization of hydrogel microstructures. This CSM method allows accurate measurement of the hydrogel pore size down to nanometer resolution. Furthermore, a microfluidic device was implemented to measure the hydrogel permeability (Pd) as a function of particle size and gel concentration. Among the three gels, collagen gel has the lowest complex modulus, medium pore size, and the highest loss tangent. Agarose gel exhibits the highest complex modulus, the lowest loss tangent and the smallest pore size. Collagen gel and Matrigel produced complex moduli close to that estimated for cancer ECM. The Pd of these hydrogels decreases significantly with the increase of particle size. By assessing different hydrogels' biophysical characteristics, this study provides valuable insights for tailoring their properties for various three-dimensional cancer models. Keywords: Cancer Hydrogel Extracellular matrix Biophysical properties Complex modulus Loss tangent”

PEG-PLGA and PLGA from PolySciTech used in development of advanced cancer characterization techniques

Tuesday, March 29, 2022, 1:14 PM ET

Optimal use of ligands for active nanoparticle targeting requires selecting the correct antibody to attach to the specific target cell receptor. Recently, researchers at Barcelona Institute of Science and Technology (Spain) and Eindhoven University of Technology, (Netherlands) used PLGA (Cat# AP082) and PLGA-PEG-COOH (Cat# AI078) from PolySciTech (www.polyscitech.com) as part of their research into a quantitative imaging method whereby the optimal ligand is determined prior to nanoparticle preparation by use of direct stochastic optical reconstruction microscopy. This process was used to apply a systematic and intelligent design to selection of ligands for nanoparticle targeting. This research holds promise to improve therapies against cancer in the future. Read more: Woythe, Laura, Pranav Madhikar, Natalia Feiner-Gracia, Cornelis Storm, and Lorenzo Albertazzi. "A Single-Molecule View at Nanoparticle Targeting Selectivity: Correlating Ligand Functionality and Cell Receptor Density." ACS nano (2022). https://pubs.acs.org/doi/full/10.1021/acsnano.1c08277

“Antibody-functionalized nanoparticles (NPs) are commonly used to increase the targeting selectivity toward cells of interest. At a molecular level, the number of functional antibodies on the NP surface and the density of receptors on the target cell determine the targeting interaction. To rationally develop selective NPs, the single-molecule quantitation of both parameters is highly desirable. However, techniques able to count molecules with a nanometric resolution are scarce. Here, we developed a labeling approach to quantify the number of functional cetuximabs conjugated to NPs and the expression of epidermal growth factor receptors (EGFRs) in breast cancer cells using direct stochastic optical reconstruction microscopy (dSTORM). The single-molecule resolution of dSTORM allows quantifying molecules at the nanoscale, giving a detailed insight into the distributions of individual NP ligands and cell receptors. Additionally, we predicted the fraction of accessible antibody-conjugated NPs using a geometrical model, showing that the total number exceeds the accessible number of antibodies. Finally, we correlated the NP functionality, cell receptor density, and NP uptake to identify the highest cell uptake selectivity regimes. We conclude that single-molecule functionality mapping using dSTORM provides a molecular understanding of NP targeting, aiding the rational design of selective nanomedicines.”

PLGA-PEG-COOH from PolySciTech used in development of macrophage targeting nanoparticles for treatment of inflammation

Wednesday, March 23, 2022, 2:45 PM ET

The human immune system is a complex cascade of pathways, cells, and organs which exhibits several different modes of operation. The ability to modulate or adapt the action of this system can be used for both treatment of excess inflammation (i.e. rheumatoid arthritis and other autoimmune disorders) as well as to optimize vaccine action. Recently, researchers at University of Antwerp (Belgium) used PLGA-PEG-COOH (cat# AI171) from PolySciTech (www.polyscitech.com) to create macrophage targeting nanoparticles and tracked their behavior. This research holds promise to improve therapeutic options for treatment of many different diseases. Read more: Van Hees, Sofie, Kimberley Elbrink, Marjorie De Schryver, Peter Delputte, and Filip Kiekens. "Targeting of sialoadhesin-expressing macrophages through antibody-conjugated (polyethylene glycol) poly (lactic-co-glycolic acid) nanoparticles." Journal of Nanoparticle Research 24, no. 3 (2022): 1-13. https://link.springer.com/article/10.1007/s11051-022-05451-1

“This research aims to evaluate different-sized nanoparticles consisting of (polyethylene glycol) (PEG) poly(lactic-co-glycolic acid) (PLGA), loaded with fluorescein isothiocyanate for nanoparticle uptake and intracellular fate in sialoadhesin-expressing macrophages, while being functionalized with anti-sialoadhesin antibody. Sialoadhesin is a macrophage-restricted receptor, expressed on certain populations of resident tissue macrophages, yet is also upregulated in some inflammatory conditions. The nanocarriers were characterized for nanoparticle size (84–319 nm), zeta potential, encapsulation efficiency, and in vitro dye release. Small (86 nm) antibody-functionalized PEG PLGA nanoparticles showed persisting benefit from sialoadhesin-targeting after 24 h compared to the control groups. For small (105 nm) PLGA nanoparticles, uptake rate was higher for antibody-conjugated nanoparticles, though the total amount of uptake was not enhanced after 24 h. For both plain and functionalized small-sized (PEG) PLGA nanoparticles, no co-localization between nanoparticles and (early/late) endosomes nor lysosomes could be observed after 1-, 4-, or 24-h incubation time. In conclusion, decorating (PEG) PLGA nanocarriers with anti-sialoadhesin antibodies positively impacts macrophage targeting, though it was found to be formulation-specific.”

PLGA-PEG-PLGA from PolySciTech used in development of Rapamycin delivery system

Thursday, March 17, 2022, 2:48 PM ET

Rapamycin is a macrolide exhibiting potent antitumor and immunosuppressive activity. Unfortunately it has quick clearance and lacks targeted delivery for many applications. Recently, researchers used PLGA-PEG-PLGA (AK016) from PolySciTech (www.polyscitech.com) to create rapamycin-loaded nanoparticles inside of microspheres. Researchers tested the application of this delivery system towards the treatment of hemangiomas. This research holds promise to provide for improved application of rapamycin against a variety of disease states. Read more: Li, Haitao, Xin Wang, Xiaonan Guo, Qingkun Wan, Yunfei Teng, and Jianyong Liu. "Development of rapamycin-encapsulated exosome-mimetic nanoparticles-in-PLGA microspheres for treatment of hemangiomas." Biomedicine & Pharmacotherapy 148 (2022): 112737. https://www.sciencedirect.com/science/article/pii/S0753332222001251

“Highlights: Rapamycin-encapsulated exosome-mimetic nanoparticles-in-PLGA microspheres (RNM) show slow-release of rapamycin. RNM achieved superior therapeutic efficacy against hemangiomas over rapamycin. The therapeutic efficacy of RNM was attributed to its sustained release and suppression efficacy against HemSCs. Abstract: We have previously developed several kinds of rapamycin-encapsulated nanoparticles to achieve sustained release of rapamycin to treat hemangioma. However, lack of intrinsic targeting and easy clearance by the immune system are major hurdles that artificial fabricated nanoparticles must overcome. We constructed rapamycin-encapsulated macrophage-derived exosomes mimic nanoparticles-in-microspheres (RNM), to achieve the goal of continuous targeted therapy of hemangiomas. The rapamycin-encapsulated exosome mimic nanoparticles (RN) were firstly prepared by the extrusion-based method from the U937 cells (the human macrophage cell line). After then, RN was encapsulated with PLGA (poly(lactic-co-glycolic acid)) microspheres to obtain RNM. The release profile, targeting activity, and biological activity of RN and RNM were investigated on hemangioma stem cells (HemSCs). RN has a size of 100 nm in diameter, with a rapamycin encapsulation efficacy (EE) of 83%. The prepared microspheres RNM have a particle size of ~30 µm), and the drug EE of RNM is 34%. The sustained release of RNM can remarkably be achieved for 40 days. As expected, RN and RNM showed effective inhibition of cellular proliferation, significant cellular apoptosis, and remarkable repressed expression of angiogenesis factors in HemSCs. Our results showed that RNM is an effective approach for prolonged and effective delivery of rapamycin to hemangiomas.”

PLCL from PolySciTech used in development of tissue engineering for repair of torn rotator cuff and other injuries

Thursday, March 17, 2022, 2:47 PM ET

Depending on the nature and location of an injury healing may be difficult if not impossible as some tissues have either slow regeneration rate or do not heal at all unless certain conditions are met. An example of this is torn rotator cuff, a common shoulder injury, where the damaged tendons do not heal on their own. Recently, researchers at Novartis, Columbia University, University of Pennsylvania, and University of Connecticut used Poly(lactide-co-caprolactone) PLCL from PolySciTech (www.polyscitech.com) as part of their development of tissue engineering repairs for cartiladge and ligaments. This researchs holds promise to improve traumatic wound repair in the future. Read more: Prabhath, A., Vernekar, V.N., Esdaille, C.J., Eisenberg, E., Lebaschi, A., Badon, M., Seyedsalehi, A., Dzidotor, G., Tang, X., Dyment, N. and Thomopoulos, S., 2022. Pegylated insulin‐like growth factor‐1 biotherapeutic delivery promotes rotator cuff regeneration in a rat model. Journal of Biomedical Materials Research Part A. https://onlinelibrary.wiley.com/doi/abs/10.1002/jbm.a.37378

“Tears in the rotator cuff are challenging to repair because of the complex, hypocellular, hypovascular, and movement-active nature of the tendon and its enthesis. Insulin-like Growth Factor-1 (IGF-1) is a promising therapeutic for this repair. However, its unstable nature, short half-life, and ability to disrupt homeostasis has limited its clinical translation. Pegylation has been shown to improve the stability and sustain IGF-1 levels in the systemic circulation without disrupting homeostasis. To provide localized delivery of IGF-1 in the repaired tendons, we encapsulated pegylated IGF-1 mimic and its controls (unpegylated IGF-1 mimic and recombinant human IGF-1) in polycaprolactone-based matrices and evaluated them in a pre-clinical rodent model of rotator cuff repair. Pegylated-IGF-1 mimic delivery reestablished the characteristic tendon-to-bone enthesis structure and improved tendon tensile properties within 8 weeks of repair compared to controls, signifying the importance of pegylation in this complex tissue regeneration. These results demonstrate a simple and scalable biologic delivery technology alternative to tissue-derived grafts for soft tissue repair.”

Sales Administrator Position

Wednesday, March 9, 2022, 3:37 PM ET

Recent position opening at Akina, Inc.

Details here: http://akinainc.com/employment.php

PLA and PEG-PLA from PolySciTech used in the development of PLA-graft-insulin as a drug-delivery platform

Tuesday, March 8, 2022, 1:47 PM ET

Although polyethylene glycol (PEG) is generally considered to have a good safety profile, it does present an allergic reaction in certain patients. Alternative hydrophilic blocks can enable the generation of nanoparticles/micelles without using this compound. Recently, researchers at University of Salerno (Italy) used PLA (Cat# AP005 and Cat# AP231) and mPEG-PLA (Cat# AK009) from PolySciTech (www.polyscitech.com) to graft PLA polymers onto insulin and create nanoparticles loaded with this grafted PLA-Insulin material. This research holds promise to improve therapies against cancer and other diseases which bypass the issues that affect PEG. Read more: Sardo, Carla, Teresa Mencherini, Carmela Tommasino, Tiziana Esposito, Paola Russo, Pasquale Del Gaudio, and Rita Patrizia Aquino. "Inulin-g-poly-D, L-lactide, a sustainable amphiphilic copolymer for nano-therapeutics." Drug Delivery and Translational Research (2022): 1-17. https://link.springer.com/article/10.1007/s13346-022-01135-4

“Cancer therapies started to take a big advantage from new nanomedicines on the market. Since then, research tried to better understand how to maximize efficacy while maintaining a high safety profile. Polyethylene glycol (PEG), the gold standard for nanomedicines coating design, is a winning choice to ensure a long circulation and colloidal stability, while in some cases, patients could develop PEG-directed immunoglobulins after the first administration. This lead to a phenomenon called accelerated blood clearance (ABC effect), and it is correlated with clinical failure because of the premature removal of the nanosystem from the circulation by immune mechanism. Therefore, alternatives to PEG need to be found. Here, looking at the backbone structural analogy, the hydrophilicity, flexibility, and its GRAS status, the natural polysaccharide inulin (INU) was investigated as PEG alternative. In particular, the first family of Inulin-g-poly-D,L-lactide amphiphilic copolymers (INU-PLAs) was synthesized. The new materials were fully characterized from the physicochemical point of view (solubility, 1D and 2D NMR, FT-IR, UV–Vis, GPC, DSC) and showed interesting hybrid properties compared to precursors. Moreover, their ability in forming stable colloids and to serve as a carrier for doxorubicin were investigated and compared with the already well-known and well-characterized PEGylated counterpart, polyethylene glycol-b-poly-D,L-lactide (PEG-PLA). This preliminary investigation showed INU-PLA to be able to assemble in nanostructures less than 200 nm in size and capable of loading doxorubicin with an encapsulation efficiency in the same order of magnitude of PEG-PLA analogues.

PLGA from PolySciTech used in development of wound-healing antibiotic delivery system

Monday, February 28, 2022, 11:25 AM ET

Wounds often heal poorly due to bacterial intrusion. Recently, researchers at Assiut University (Egypt) utilized PLGA from PolySciTech (www.polyscitech.com) to create silk-PLGA nanoparticles to improve wound healing. This research holds promise to improve treatments against infected wounds. Read more: Abd El-Aziz, Fatma El-Zahraa A., Helal F. Hetta, Basma N. Abdelhamid, and Noura H. Abd Ellah. "Antibacterial and wound-healing potential of PLGA/spidroin nanoparticles: a study on earthworms as a human skin model." Nanomedicine 0 (2022). https://www.futuremedicine.com/doi/abs/10.2217/nnm-2021-0325

“Aim: The essential protein element of spider silk ‘spidroin’ was used to assess its impact on the wound-healing process. Methods: Spidroin nanoparticles (NPs) were prepared using poly(lactic-co-glycolic acid) polymer (PLGA/spidroin NPs) at different weight ratios (5:1, 10:1, 15:1) and were in vitro characterized. The optimized NPs were tested in vitro for release and antibacterial activity. To assess wound-healing effects, NPs were topically applied on surgically induced injuries in Allolobophora caliginosa earthworms as a robust human skin model. Results: Optimized NPs (173 ± 3 nm) revealed considerable antibacterial effect against Staphylococcus aureus and Escherichia coli. After 4 days of NPs application on wounds, macroscopical and histological examinations revealed a significant reduction in wound and re-epithelialization times. Conclusion: PLGA/spidroin NPs may represent a promising option for wound repair.”

PLGA from PolySciTech used in development of doxorubicin-loaded particles for chemoimmunotherapy applications

Monday, February 28, 2022, 11:24 AM ET

Immunogenic cell death (ICD) is an immune response against cancers which can be leveraged to eliminate tumors. Recently, researchers at Korea University and Korea Institute of Science and Technology utilized PLGA (cat# AP081) from PolySciTech (www.polyscitech.com) to create doxorubicin loaded nanoparticles for inducing ICD. This research holds promise to improve therapies against cancer in the future. Read more: Kim, Jeongrae, Yongwhan Choi, Suah Yang, Jaewan Lee, Jiwoong Choi, Yujeong Moon, Jinseong Kim et al. "Sustained and Long-Term Release of Doxorubicin from PLGA Nanoparticles for Eliciting Anti-Tumor Immune Responses." Pharmaceutics 14, no. 3 (2022): 474. https://www.mdpi.com/1511014

“Immunogenic cell death (ICD) is a powerful trigger eliciting strong immune responses against tumors. However, traditional chemoimmunotherapy (CIT) does not last long enough to induce sufficient ICD, and also does not guarantee the safety of chemotherapeutics. To overcome the disadvantages of the conventional approach, we used doxorubicin (DOX) as an ICD inducer, and poly(lactic-co-glycolic acid) (PLGA)-based nanomedicine platform for controlled release of DOX. The diameter of 138.7 nm of DOX-loaded PLGA nanoparticles (DP-NPs) were stable for 14 days in phosphate-buffered saline (PBS, pH 7.4) at 37 ◦C. Furthermore, DOX was continuously released for 14 days, successfully inducing ICD and reducing cell viability in vitro. Directly injected DP-NPs enabled the remaining of DOX in the tumor site for 14 days. In addition, repeated local treatment of DP-NPs actually lasted long enough to maintain the enhanced antitumor immunity, leading to increased tumor growth inhibition with minimal toxicities. Notably, DP-NPs treated tumor tissues showed significantly increased maturated dendritic cells (DCs) and cytotoxic T lymphocytes (CTLs) population, showing enhanced antitumor immune responses. Finally, the therapeutic efficacy of DP-NPs was maximized in combination with an anti-programmed death-ligand 1 (PD-L1) antibody (Ab). Therefore, we expect therapeutic efficacies of cancer CIT can be maximized by the combination of DP-NPs with immune checkpoint blockade (ICB) by achieving proper therapeutic window and continuously inducing ICD, with minimal toxicities.”

PLGA-PEG-PLGA Thermogel from PolySciTech used in study to understand neointimal hyperplasia

Wednesday, February 23, 2022, 4:23 PM ET

Neointimal hyperplasia is a process by which injured vessels will initiate in-growth of tissue. This process is particularly problematic during stenosis as the growing tissue blocks the interior of the stent and recloses the vessel. Recently, researchers from University of Virginia and Ohio State University used PLGA-PEG-PLGA (Cat# AK012) from PolySciTech (www.polyscitech.com) to delivery EZH1/2 inhibitor (UNC1999) as a way to model healing with this pathway blocked off. This understanding of vessel healing process can assist with designing more effective means of stenosis. Read more: Zhang, Mengxue, Go Urabe, Hatice Gulcin Ozer, Xiujie Xie, Amy Webb, Takuro Shirasu, Jing Li et al. "Angioplasty induces epigenomic remodeling in injured arteries." Life Science Alliance 5, no. 5 (2022). https://www.life-science-alliance.org/content/5/5/e202101114.abstract

“Abstract: Neointimal hyperplasia/proliferation (IH) is the primary etiology of vascular stenosis. Epigenomic studies concerning IH have been largely confined to in vitro models, and IH-underlying epigenetic mechanisms remain poorly understood. This study integrates information from in vivo epigenomic mapping, conditional knockout, gene transfer and pharmacology in rodent models of IH. The data from injured (IH-prone) rat arteries revealed a surge of genome-wide occupancy by histone-3 lysine-27 trimethylation (H3K27me3), a gene-repression mark. This was unexpected in the traditional view of prevailing post-injury gene activation rather than repression. Further analysis illustrated a shift of H3K27me3 enrichment to anti-proliferative genes, from pro-proliferative genes where gene-activation mark H3K27ac(acetylation) accumulated instead. H3K27ac and its reader BRD4 (bromodomain protein) co-enriched at Ezh2; conditional BRD4 knockout in injured mouse arteries reduced H3K27me3 and its writer EZH2, which positively regulated another pro-IH chromatin modulator UHRF1. Thus, results uncover injury-induced loci-specific H3K27me3 redistribution in the epigenomic landscape entailing BRD4→EZH2→UHRF1 hierarchical regulations. Given that these players are pharmaceutical targets, further research may help improve treatments of IH.”

PLGA from PolySciTech used in development of cancer immunotherapy platform

Wednesday, February 23, 2022, 4:22 PM ET

Immunotherapy is a process by which the immune system is triggered to attack the cancer cells directly. Researchers at Sungkyunkwan University used PLGA from PolySciTech (www.polyscitech.com) to create microparticles encapsulated with tumor lysate as a means to initiate an immune response against the cancer. This research holds promise to improve immunotherapy against cancer. Read more: Lee, Jae Ah, Jung Min Shin, Seok Ho Song, Chan Ho Kim, Soyoung Son, Sol Shin, and Jae Hyung Park. "Recruitment of dendritic cells using ‘find-me’ signaling microparticles for personalized cancer immunotherapy." Biomaterials (2022): 121412. https://www.sciencedirect.com/science/article/abs/pii/S0142961222000515

“Abstract: Therapeutic cancer vaccines have attracted attention because of their potential to prime cytotoxic T cells, which are highly antigen (Ag)-specific, allowing personalized cancer immunotherapy. However, because of their low immunogenicity, cancer vaccines have been used in only a few types of cancers in clinics, primarily because of the poor Ag presentation of dendritic cells (DCs). To address these limitations of cancer vaccines, we show that ‘find-me’ signaling polymeric microparticles (F-PMs) bearing tumor lysate as an Ag can efficiently recruit DCs and facilitate antigen presentation. When subcutaneously injected into tumor-bearing mice, F-PMs significantly increased mature DCs in tumor-draining lymph nodes by eliciting adenosine triphosphate (ATP)-induced chemotaxis, resulting in high antitumor efficacy. CD8+ cytotoxic T cells were remarkably enriched in the tumor microenvironment following co-administration of an immune checkpoint inhibitor with F-PMs. We demonstrated that F-PMs elicit a robust antitumor immune response, which may provide a promising therapeutic option for cancer treatment.”

Closed due to weather

Thursday, February 17, 2022, 4:39 PM ET

Akina, Inc. Has closed as of 4pm (2/17/22) due to severe weather. Plan is to be open tomorrow.

Coming Soon: New PolySciTech Website Look

Wednesday, February 16, 2022, 11:00 AM ET

Coming soon to a www.polyscitech.com near you. We’re revamping our website to make it easier for customers to navigate and to modernize the purchasing process for PolySciTech Products and to find the item you are looking for easily. Same company. Same polymers. New look.

PEG-PLGA from PolySciTech used in development of Rebamipide-loaded nanoparticles for joint arthritis treatment

Wednesday, February 16, 2022, 10:59 AM ET

Osteoarthritis is a progressive disease in which immune system attacks the joint tissue often leading to complete failure of the joint. Recently, researchers at Korea University and Chung-Ang University (Korea) utilized mPEG-PLGA (Cat# AK037) from PolySciTech (www.polyscitech.com) to create nanoparticles loaded with Rebamipide and used these to investigate the treatment of arthritis in a rat model. This research holds promise for improved arthritis therapy. Read more: Kim, Sung Eun, Sung Jae Choi, Kyeongsoon Park, Hak-Jun Kim, Gwan Gyu Song, and Jae Hyun Jung. "Intra-Articular Injection of Rebamipide-Loaded Nanoparticles Attenuate Disease Progression and Joint Destruction in Osteoarthritis Rat Model: A Pilot Study." Cartilage 13, no. 1 (2022): 19476035211069250. https://journals.sagepub.com/doi/full/10.1177/19476035211069250

“Abstract: Objective: Rebamipide has antioxidant effects and is a drug with a local rather than systemic mechanism of action. Oxidative stress and inflammation in chondrocytes are the major factors contributing to the development and progression of osteoarthritis (OA). Since OA is mainly developed in weight bearing or overused joints, the locally sustained therapy is effective for targeting inflammatory component of OA. We investigated the effects of intra-articular injection of rebamipide loaded nanoparticles (NPs) in OA rat model. Design: We fabricated rebamipide-loaded methoxy poly(ethylene glycol)-b-poly(D,L-lactide) (mPEG-PDLLA) and poly(D, L-lactide-co-glycolide) (PLGA) NPs that allow the sustained release of rebamipide. In vitro, chondrocytes from rat were used to investigate the cytotoxicity and anti-inflammatory effect of rebamipide-loaded NPs. In vivo, monosodium iodoacetate (MIA)-induced OA rats were divided into 7 groups, consisting of healthy control rats and rats injected with MIA alone or in combination with NPs, rebamipide (1 mg)/NPs, rebamipide (10 mg)/NPs, rebamipide (10 mg) solution, or oral administration. Results: In vitro, rebamipide/NPs dose-dependently suppressed the mRNA levels of pro-inflammatory mediators, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, matrix metalloproteinase (MMP)-3, MMP-13, and cyclo-oxygenase-2. In vivo, the mRNA levels of pro-inflammatory components most markedly decreased in the intra-articularly injected rebamipide (10 mg)/NP group compared to other groups. Macroscopic, radiographic, and histological evaluations showed that the intra-articular injection of rebamipide/NPs inhibited cartilage degeneration more than rebamipide solution or rebamipide administration. Conclusions: Using a chemically induced rat model of OA, intra-articular delivery of rebamipide was associated with decreased local and systemic inflammatory response decreased joint degradation and arthritic progression. Keywords: rebamipide, methoxy poly(ethylene glycol)-b-poly(D,L-lactide), poly(D, L-lactide-co-glycolide), intra-articular injection, osteoarthritis”

mPEG-PLA from PolySciTech used in the development of Resveratrol-loaded nanoparticles for cancer therapy

Wednesday, February 16, 2022, 10:58 AM ET

Resveratrol is a naturally occurring chemical which has many biological benefits but poor circulation and uptake. Recently, researchers at Curtin University (Australia) utilized PEG-PLA (AK070) from PolySciTech (www.polyscitech.com) to create resveratrol loaded nanoparticles to improve its bioavailability and circulation time as a treatment option for cancer. This research holds promise to enable the use of poorly soluble compounds for cancer therapy. Read more: Yee, Yan Jing, Heather AE Benson, and Yan Chen. "Evaluation of novel conjugated resveratrol polymeric nanoparticles in reduction of plasma degradation, hepatic metabolism and its augmentation of anticancer activity in vitro and in vivo." International Journal of Pharmaceutics (2022): 121499. https://www.sciencedirect.com/science/article/pii/S0378517322000527

“Abstract: Resveratrol (RSV) is a natural product with multiple biological benefits including anticancer properties. Unfortunately, its biological benefits are limited by its low bioavailability and rapid hepatic metabolism and degradation in the body. The aim of this study was to develop an effective delivery system for RSV that would enhance the plasmatic stability and decrease the metabolism rate of RSV through a dual strategy of chemical modification and nanoparticle formulation. The effectiveness of this strategy was tested for the application of RSV anticancer treatment in a mouse cancer model. Chemical modification of RSV was achieved by conjugating RSV to a low molecular weight co-polymer mPEG-PLA. This conjugated RSV together with free RSV were formulated into mPEG-PLA nanoparticles (conjugated RSV NPs). These NPs showed a stable plasma stability profile and decreased liver metabolism rate compared to nanoparticles encapsulating free RSV in mPEG-PLA (encapsulated RSV NPs) and free RSV alone. However, in vitro cell studies using B16-F10 cancer cells showed that conjugated RSV NPs were less effective compared to encapsulated RSV NPs, possibly due to the lack of biotransformation of conjugated RSV to the active form RSV in the simple cell studies. To study the actual effect of our strategy, an in vivo C57BL/6J mouse model with subcutaneous B16-F10 melanoma using intraperitoneal administration was used to reveal the relationship between the improved plasma stability and reduced liver metabolism rate of RSV in conjugated RSV NPs, and suppression of the tumour growth in mice. In vivo, a better tumour suppression trend with conjugated RSV NPs was noted. Our study suggests that the use of chemical conjugation with NP formulation is an effective strategy to reduce the degradation and metabolism rate of RSV and consequently increase the antitumour activity of RSV in vivo. This strategy has potential to be further developed for the suppression of early growth of tumours with no side effects. Keywords Resveratrol Low molecular weight polymeric nanoparticles Antitumour activity Liver metabolism Degradation Conjugation. Abbreviations: RSV Resveratrol NPs Nanoparticles mPEG-PLA Methoxypoly(ethylene glycol)-poly(lactide) DL Drug loading capacity HPLC High Performance liquid chromatography EE Entrapment efficiency HLM Human liver microsomes CGM Cell growth media”

These posts are syndicated from John Garner's blog at http://jgakinainc.blogspot.com/ where you can post a question or comment. (Load took 0.40756297111511 seconds)


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