scholarly journals Identification of peptide coatings that enhance diffusive transport of nanoparticles through the tumor microenvironment

2019 ◽  
Author(s):  
Rashmi P. Mohanty ◽  
Xinquan Liu ◽  
Jae Y. Kim ◽  
Xiujuan Peng ◽  
Sahil Bhandari ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Physicochemical Properties ◽  
Pancreatic Tumor ◽  
Chemical Space ◽  
Ex Vivo ◽  
Negative Control ◽  
Peptide Ligand ◽  
Diffusive Transport ◽  
Surface Chemistries

In solid tumors, increasing drug penetration promotes their regression and improves the therapeutic index of compounds. However, the heterogeneous extracellular matrix (ECM) acts a steric and interaction barrier that hinders effective transport of therapeutics, including nanomedicines. Specifically, the interactions between the ECM and surface physicochemical properties of nanomedicines (e.g. charge, hydrophobicity) impedes their diffusion and penetration. To address the challenges using existing surface chemistries, we used peptide-presenting phage libraries as a high-throughput approach to screen and identify peptides as coatings with desired physicochemical properties that improve diffusive transport through the tumor microenvironment. Through iterative screening against the ECM and identification by next-generation DNA sequencing and analysis, we selected individual clones and measured their transport by diffusion assays. Here, we identified a net-neutral charge, hydrophilic peptide P4 that facilitates significantly higher diffusive transport of phage than negative control through in vitro tumor ECM. Through alanine mutagenesis, we confirmed that the hydrophilicity, charge, and their spatial ordering impact diffusive transport. P4 phage clone exhibited almost 200-fold improved uptake in ex vivo pancreatic tumor xenografts compared to the negative control. Nanoparticles coated with P4 exhibited ∼40-fold improvement in diffusivity in pancreatic tumor tissues, and P4-coated particles demonstrated less hindered diffusivity through the ECM compared to particles functionalized with gold standard poly(ethylene) glycol or iRGD peptide ligand. By leveraging the power of molecular diversity using phage display, we can greatly expand the chemical space of surface chemistries that can improve the transport of nanomedicines through the complex tumor microenvironment to ultimately improve their efficacy.Abstract Figure

scholarly journals A Tumbling Magnetic Microrobot System for Biomedical Applications

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 861
Author(s):  
Elizabeth E. Niedert ◽  
Chenghao Bi ◽  
Georges Adam ◽  
Elly Lambert ◽  
Luis Solorio ◽  
...  
Keyword(s):  
Ultrasound Imaging ◽  
Biomedical Applications ◽  
Imaging System ◽  
Ex Vivo ◽  
Negative Control ◽  
Circular Path ◽  
Rotational Axis ◽  
Significant Difference

A microrobot system comprising an untethered tumbling magnetic microrobot, a two-degree-of-freedom rotating permanent magnet, and an ultrasound imaging system has been developed for in vitro and in vivo biomedical applications. The microrobot tumbles end-over-end in a net forward motion due to applied magnetic torque from the rotating magnet. By turning the rotational axis of the magnet, two-dimensional directional control is possible and the microrobot was steered along various trajectories, including a circular path and P-shaped path. The microrobot is capable of moving over the unstructured terrain within a murine colon in in vitro, in situ, and in vivo conditions, as well as a porcine colon in ex vivo conditions. High-frequency ultrasound imaging allows for real-time determination of the microrobot’s position while it is optically occluded by animal tissue. When coated with a fluorescein payload, the microrobot was shown to release the majority of the payload over a 1-h time period in phosphate-buffered saline. Cytotoxicity tests demonstrated that the microrobot’s constituent materials, SU-8 and polydimethylsiloxane (PDMS), did not show a statistically significant difference in toxicity to murine fibroblasts from the negative control, even when the materials were doped with magnetic neodymium microparticles. The microrobot system’s capabilities make it promising for targeted drug delivery and other in vivo biomedical applications.

scholarly journals The MEMIC: An ex vivo system to model the complexity of the tumor microenvironment

2021 ◽  
Author(s):  
Libuše Janská ◽  
Libi Anandi ◽  
Nell C. Kirchberger ◽  
Zoran S. Marinkovic ◽  
Logan T. Schachtner ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Ex Vivo ◽  
Tumor Stroma ◽  
Stem Cell Differentiation ◽  
Blood Stream ◽  
Direct Access ◽  
Ex Vivo Model

There is an urgent need for accurate, scalable, and cost-efficient experimental systems to model the complexity of the tumor microenvironment. Here, we detail how to fabricate and use the Metabolic Microenvironment Chamber (MEMIC) – a 3D-printed ex vivo model of intratumoral heterogeneity. A major driver of the cellular and molecular diversity in tumors is the accessibility to the blood stream that provides key resources such as oxygen and nutrients. While some tumor cells have direct access to these resources, many others must survive under progressively more ischemic environments as they reside further from the vasculature. The MEMIC is designed to simulate the differential access to nutrients and allows co-culturing different cell types, such as tumor and immune cells. This system is optimized for live imaging and other microscopy-based approaches, and it is a powerful tool to study tumor features such as the effect of nutrient scarcity on tumor-stroma interactions. Due to its adaptable design and full experimental control, the MEMIC provide insights into the tumor microenvironment that would be difficult to obtain via other methods. As a proof of principle, we show that cells sense gradual changes in metabolite concentration resulting in multicellular spatial patterns of signal activation and cell proliferation. To illustrate the ease of studying cell-cell interactions in the MEMIC, we show that ischemic macrophages reduce epithelial features in neighboring tumor cells. We propose the MEMIC as a complement to standard in vitro and in vivo experiments, diversifying the tools available to accurately model, perturb, and monitor the tumor microenvironment, as well as to understand how extracellular metabolites affect other processes such as wound healing and stem cell differentiation.

scholarly journals Study of Two Bovine Bone Blocks (Sintered and Non-Sintered) Used for Bone Grafts: Physico-Chemical Characterization and In Vitro Bioactivity and Cellular Analysis

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 452 ◽  
Author(s):  
Sergio Gehrke ◽  
Patricia Mazón ◽  
Leticia Pérez-Díaz ◽  
José Calvo-Guirado ◽  
Pablo Velásquez ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Structural Characteristics ◽  
Mercury Porosimetry ◽  
Negative Control ◽  
Infrared Spectrometry ◽  
Mechanical Resistance ◽  
Bovine Bone ◽  
In Vitro Bioactivity ◽  
Cellular Analysis

In this work, the physicochemical properties and in vitro bioactivity and cellular viability of two commercially available bovine bone blocks (allografts materials) with different fabrication processes (sintered and not) used for bone reconstruction were evaluated in order to study the effect of the microstructure in the in vitro behavior. Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, mechanical resistance of blocks, mercury porosimetry analysis, in vitro bioactivity, and cell viability and proliferation were performed to compare the characteristics of both allograft materials against a synthetic calcium phosphate block used as a negative control. The herein presented results revealed a very dense structure of the low-porosity bovine bone blocks, which conferred the materials’ high resistance. Moreover, relatively low gas, fluid intrusion, and cell adhesion were observed in both the tested materials. The structural characteristics and physicochemical properties of both ceramic blocks (sintered and not) were similar. Finally, the bioactivity, biodegradability, and also the viability and proliferation of the cells was directly related to the physicochemical properties of the scaffolds.

scholarly journals In Vitro and Ex Vivo Evaluation of Nepafenac-Based Cyclodextrin Microparticles for Treatment of Eye Inflammation

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 709 ◽  
Author(s):  
Blanca Lorenzo-Veiga ◽  
Patricia Diaz-Rodriguez ◽  
Carmen Alvarez-Lorenzo ◽  
Thorsteinn Loftsson ◽  
Hakon Hrafn Sigurdsson
Keyword(s):  
Zeta Potential ◽  
Physicochemical Properties ◽  
Inflammatory Mediators ◽  
Ex Vivo ◽  
Posterior Segment ◽  
Inflammatory Activity ◽  
Commercial Formulation ◽  
Anti Inflammatory ◽  
Negative Zeta Potential

The aim of this study was to design and evaluate novel cyclodextrin (CD)-based aggregate formulations to efficiently deliver nepafenac topically to the eye structure, to treat inflammation and increase nepafenac levels in the posterior segment, thus attenuating the response of inflammatory mediators. The physicochemical properties of nine aggregate formulations containing nepafenac/γ-CD/hydroxypropyl-β (HPβ)-CD complexes as well as their rheological properties, mucoadhesion, ocular irritancy, corneal and scleral permeability, and anti-inflammatory activity were investigated in detail. The results were compared with a commercially available nepafenac suspension, Nevanac® 3 mg/mL. All formulations showed microparticles, neutral pH, and negative zeta potential (–6 to –27 mV). They were non-irritating and nontoxic and showed high permeation through bovine sclera. Formulations containing carboxymethyl cellulose (CMC) showed greater anti-inflammatory activity, even higher than the commercial formulation, Nevanac® 0.3%. The optimized formulations represent an opportunity for topical instillation of drugs to the posterior segment of the eye.

862 Targeting PSGL-1, a novel macrophage checkpoint, repolarizes suppressive macrophages, induces an inflammatory tumor microenvironment, and suppresses tumor growth

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A915-A915
Author(s):  
Phuong Nguyen ◽  
Ryan Phennicie ◽  
Kevin Kauffman ◽  
Dominika Nowakowska ◽  
Mohammad Zafari ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Microenvironment ◽  
Tumor Growth ◽  
Ex Vivo ◽  
Tnf Alpha ◽  
M2 Macrophages ◽  
Humanized Mouse ◽  
Cellular Assays ◽  
Pdx Model

BackgroundMacrophages play an important role in cancer by modulating both the innate and adaptive parts of the immune system. In non-pathological conditions, multiple subsets of macrophages balance the immune response. In cancer, M2-like immune-suppressive tumor-associated macrophages (TAMs) dominate the tumor microenvironment (TME). TAMs promote tumor growth, support neo-angiogenesis and enable metastasis formation. Macrophage modulators driving macrophage repolarization from the M2-like to a pro-inflammatory M1-like phenotype are an attractive novel class of cancer immunotherapy. Here we present identification, validation, and pre-clinical data of a novel macrophage checkpoint, PSGL-1, which supports targeting this molecule for immune-oncology.MethodsTo assess the therapeutic potential of using anti-PSGL-1 antibodies to convert macrophage phenotype and the tumor microenvironment toward a more inflammatory state, we employed in vitro primary macrophage and multi-cellular assays, ex vivo patient-derived tumor cultures, and a humanized mouse PDX model.ResultsWithin the multiple subsets of macrophages, PSGL-1 is expressed at high levels on immune-suppressive TAMs and in vitro differentiated M2 macrophages. We show that targeting PSGL-1 via an antagonistic antibody repolarized M2 macrophages to a more M1-like state, both phenotypically and functionally as assessed in primary in vitro macrophage assays. Further, these repolarized M1-like macrophages enhanced the inflammatory response in complex multi-cellular assays, including SEB stimulated PBMC assays and mixed-lymphocyte reactions (MLRs).To establish a pre-clinical proof-of-concept for targeting PSGL-1, we turned to ex vivo cultures of fresh patient-derived primary tumors, where the complexity of the TME can be most preserved. RNA-seq data show that ex vivo cultures treated with anti-PD-1 antibody recapitulate TME changes in anti-PD-1 treated patients, including a strong T-cell IFN-gamma signature and a reduction in oncogenic pathway activation. Blocking PSGL-1 resulted in a robust pro-inflammatory signature driven by TNF-alpha/NF-kappa-B and chemokine-mediated signaling. The increase in TNF-alpha signaling was accompanied by reduction in oxidative phosphorylation and fatty acid metabolism. The increase in pro-inflammatory cytokine and chemokine production was confirmed by measuring secreted protein levels, further confirming the re-polarization of macrophages within a tumor setting.Lastly, we employed a humanized mouse PDX model of melanoma and show that anti-PSGL-1 treatment resulted in suppression of tumor growth favorably compared to anti-PD-1. At the cellular and molecular levels, anti-PSGL-1 treatment lead to a more enhanced inflammatory microenvironment, including a reduced M2:M1 macrophage ratio, increased antigen presentation, pro-inflammatory mediators, and effector T cell infiltration and activation.ConclusionsOur data support anti-PSGL-1 as a macrophage repolarizing agent and an effective macrophage-targeted therapy for Immuno-Oncology.

scholarly journals Investigation of Nano-Bio Interactions within a Pancreatic Tumor Microenvironment for the Advancement of Nanomedicine in Cancer Treatment

2021 ◽  
Vol 28 (3) ◽  
pp. 1962-1979
Author(s):  
Abdulaziz Alhussan ◽  
Kyle Bromma ◽  
Ece Pinar Demirci Bozdoğan ◽  
Andrew Metcalfe ◽  
Joanna Karasinska ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Growth ◽  
Cancer Cells ◽  
Pancreatic Tumor ◽  
Cell Types ◽  
Time Period ◽  
Physical And Chemical ◽  
Pancreatic Origin

Pancreatic cancer is one of the deadliest types of cancer, with a five-year survival rate of only 10%. Nanotechnology offers a novel perspective to treat such deadly cancers through their incorporation into radiotherapy and chemotherapy. However, the interaction of nanoparticles (NPs) with cancer cells and with other major cell types within the pancreatic tumor microenvironment (TME) is yet to be understood. Therefore, our goal is to shed light on the dynamics of NPs within a TME of pancreatic origin. In addition to cancer cells, normal fibroblasts (NFs) and cancer-associated fibroblasts (CAFs) were examined in this study due to their important yet opposite roles of suppressing tumor growth and promoting tumor growth, respectively. Gold nanoparticles were used as the model NP system due to their biocompatibility and physical and chemical proprieties, and their dynamics were studied both quantitatively and qualitatively in vitro and in vivo. The in vitro studies revealed that both cancer cells and CAFs take up 50% more NPs compared to NFs. Most importantly, they all managed to retain 70–80% of NPs over a 24-h time period. Uptake and retention of NPs within an in vivo environment was also consistent with in vitro results. This study shows the paradigm-changing potential of NPs to combat the disease.

scholarly journals In vitro model of inflammatory, hypoxia, and cancer stem cell signaling in pancreatic cancer using heterocellular 3-dimensional spheroids

2018 ◽  
Author(s):  
Megha Suresh ◽  
George Mattheolabakis ◽  
Amit Singh ◽  
Mansoor Amiji
Keyword(s):  
Pancreatic Cancer ◽  
Stem Cell ◽  
Tumor Microenvironment ◽  
Cancer Stem Cell ◽  
Cancer Cells ◽  
Cell Lines ◽  
Pancreatic Tumor ◽  
Stem Cell Markers ◽  
3 Dimensional

AbstractIntroductionAs one of the most aggressive cancers worldwide, pancreatic cancer is associated with an extremely poor prognosis. The pancreatic tumor microenvironment consists of cancer cells and other tumor associated cells. Cross-talk between these different cell types through various signaling molecules results in the development of a more aggressive and malignant phenotype. Additionally, due to the highly dysregulated vasculature of tumors, the inner tumor core becomes hypoxic and eventually necrotic. Therefore, there is a need for the development of a physiologically relevant in vitro model that recapitulates these dynamic cell-cell interactions and the 3-dimensional (3D) structure of pancreatic tumors.MethodsFour different 3D co-culture spheroid models using different combinations of Panc-1 tumor cells, J774.A1 macrophages, and NIH-3T3 fibroblast cell lines were reproducibly developed using the hanging drop technique in order to mimic the tumor microenvironment and to evaluate the differences in expression of various inflammatory, hypoxia, and cancer stem cell markers, including IL-8, TNF-α, TGF-β, HIF-1α HIF-2α, SCF, and LDH-A. Additionally, immunofluorescence studies were employed to investigate whether these spheroids tested positive for a cancer stem cell population.ResultsPronounced differences in morphology as well as expression of signalling markers were observed using qPCR, indicative of strong influences of co-culturing different cell lines. These models also tested positive for cancer stem cell (CSCs) markers based on immunofluorescence and qPCR analysis.ConclusionOur results demonstrate the potential of 3D co-culture spheroid models to capture the inflammatory and hypoxic markers of pancreatic tumor microenvironment. We further demonstrate the presence of cancer cells with stem cell markers, similar to actual pancreatic cancer tumor. These spheroids present excellent in vitro system to study tumor-immune-stromal cell interactions as well as test deliverability of potential therapeutics in the tumor microenvironment with accurate physical and physiological barriers.

FORMULATION AND EVALUATION OF DARIFENACIN HYDROBROMIDE TRANSDERMAL PATCH

2021 ◽  
pp. 12-14
Author(s):  
Aparna Reddy K ◽  
Latha K ◽  
Naseeb Basha Shaik ◽  
Sushma B ◽  
Haritha T ◽  
...  
Keyword(s):  
Drug Release ◽  
Physicochemical Properties ◽  
Ex Vivo ◽  
Skin Irritation ◽  
Drug Level ◽  
Immediate Release ◽  
Tween 20 ◽  
Transdermal Patch ◽  
Weight Variation

The aim of present study is to formulate and characterize darifenacin hydrobromide transdermal patch and the effects of non-ionic surfactants span 20 and tween 20 on drug permeation were studied. Transdermal patches were prepared by solvent casting method using PVA, PVP, HPMC E5, HPMC E15 polymers. Propylene glycol and Glycerol were used as plasticizers and Span 20 and Tween 20 were used as permeation enhancers. The prepared patches were evaluated for physicochemical properties like drug content, thickness, weight variation, folding endurance, moisture uptake, watervapour transmission studies. Physicochemical properties have shown better. Drug release studies by in-vitro diffusion, ex-vivo permeation as well as skin irritation. Formulations DPAT2, DPLT3 showed better drug release rate, ux and Q when compared to DPAS2, DPLS2. From the results it was concluded that darifenacin hydrobromide transdermal patch 24 (DPAT2) formulation would reduce the administration frequency, side effects and may avoid uctuations of drug level in the blood in comparison to immediate release formulations which might enhance the patient compliance.

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