Browsing by Author "Dickinson, Mary E."
Now showing 1 - 10 of 10
Results Per Page
Sort Options
Item Antioxidant Carbon Particles Improve Cerebrovascular Dysfunction Following Traumatic Brain Injury(American Chemical Society, 2012) Bitner, Brittany R.; Marcano, Daniela C.; Berlin, Jacob M.; Fabian, Roderic H.; Cherian, Leela; Culver, James C.; Dickinson, Mary E.; Robertson, Claudia S.; Pautler, Robia G.; Kent, Thomas A.; Tour, James M.; Smalley Institute for Nanoscale Science and TechnologyInjury to the neurovasculature is a feature of brain injury and must be addressed to maximize opportunity for improvement. Cerebrovascular dysfunction, manifested by reduction in cerebral blood flow (CBF), is a key factor that worsens outcome after traumatic brain injury (TBI), most notably under conditions of hypotension. We report here that a new class of antioxidants, poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), which are nontoxic carbon particles, rapidly restore CBF in a mild TBI/hypotension/resuscitation rat model when administered during resuscitation--a clinically relevant time point. Along with restoration of CBF, there is a concomitant normalization of superoxide and nitric oxide levels. Given the role of poor CBF in determining outcome, this finding is of major importance for improving patient health under clinically relevant conditions during resuscitative care, and it has direct implications for the current TBI/hypotension war-fighter victims in the Afghanistan and Middle East theaters. The results also have relevancy in other related acute circumstances such as stroke and organ transplantation.Item Cancer-Associated Fibroblasts Induce a Collagen Cross-link Switch in Tumor Stroma(American Association for Cancer Research, 2016) Pankova, Daniela; Chen, Yulong; Terajima, Masahiko; Schliekelman, Mark J.; Baird, Brandi N.; Fahrenholtz, Monica; Sun, Li; Gill, Bartley J.; Vadakkan, Tegy J.; Kim, Min P.; Ahn, Young-Ho; Roybal, Jonathon D.; Liu, Xin; Cuentas, Edwin Roger Parra; Rodriguez, Jaime; Wistuba, Ignacio I.; Creighton, Chad J.; Gibbons, Don L.; Hicks, John M.; Dickinson, Mary E.; West, Jennifer L.; Grande-Allen, K. Jane; Hanash, Samir M.; Yamauchi, Mitsuo; Kurie, Jonathan M.Intratumoral collagen cross-links heighten stromal stiffness and stimulate tumor cell invasion, but it is unclear how collagen cross-linking is regulated in epithelial tumors. To address this question, we used KrasLA1 mice, which develop lung adenocarcinomas from somatic activation of a KrasG12D allele. The lung tumors in KrasLA1 mice were highly fibrotic and contained cancer-associated fibroblasts (CAF) that produced collagen and generated stiffness in collagen gels. In xenograft tumors generated by injection of wild-type mice with lung adenocarcinoma cells alone or in combination with CAFs, the total concentration of collagen cross-links was the same in tumors generated with or without CAFs, but coinjected tumors had higher hydroxylysine aldehyde–derived collagen cross-links (HLCC) and lower lysine-aldehyde–derived collagen cross-links (LCCs). Therefore, we postulated that an LCC-to-HLCC switch induced by CAFs promotes the migratory and invasive properties of lung adenocarcinoma cells. To test this hypothesis, we created coculture models in which CAFs are positioned interstitially or peripherally in tumor cell aggregates, mimicking distinct spatial orientations of CAFs in human lung cancer. In both contexts, CAFs enhanced the invasive properties of tumor cells in three-dimensional (3D) collagen gels. Tumor cell aggregates that attached to CAF networks on a Matrigel surface dissociated and migrated on the networks. Lysyl hydroxylase 2 (PLOD2/LH2), which drives HLCC formation, was expressed in CAFs, and LH2 depletion abrogated the ability of CAFs to promote tumor cell invasion and migration.Item Engineering 3D in vitro models of lung adenocarcinoma(2019-02-15) Gibson, Sydney Michelle; Dickinson, Mary E.; Grande-Allen, Kathryn J.Lung cancer is the most lethal common cancer worldwide. Lung adenocarcinoma is the most common lung cancer subtype and tends to be aggressive and resistant to chemotherapy. With few targeted treatment options available to patients, there is a need to develop new therapeutics that can stop its spread in the body. Identifying the invasion and migration mechanisms used by lung adenocarcinoma will help us understand it’s spread. Cellular and matrix elements of the tumor microenvironment directly impact tumor migration, but the field lacks information on how lung adenocarcinoma responds to microenvironmental stimuli. Furthermore, these stimuli – including cellular components and matrix characteristics – can have compounding effects that can change tumor migration and invasion behaviors. This dissertation describes the development of two 3D in vitro models for studying lung adenocarcinoma migration behaviors in response to matrix architecture, cancer associated fibroblasts, and macrophages. These models investigate how lung adenocarcinoma tumor cells interact with surrounding stromal cells in confined and unconfined 3D spaces and in collagen matrices of varying densities. Our findings suggest that matrix architecture can influence the migration behaviors of CAFs which, in turn, alter lung adenocarcinoma movement and invasion. Macrophages are also investigated as potential influencers in lung adenocarcinoma metastasis. A better understanding of lung adenocarcinoma’s migration and invasion mechanisms in response to its microenvironment could lead to new strategies for targeted lung adenocarcinoma therapies.Item Fibulin-2 Is a Driver of Malignant Progression in Lung Adenocarcinoma(Public Library of Science, 2013) Baird, Brandi N.; Schliekelman, Mark J.; Ahn, Young-Ho; Chen, Yulong; Roybal, Jonathon D.; Gill, Bartley J.; Mishra, Dhruva K.; Erez, Baruch; OﾒReilly, Michael; Yang, Yanan; Patel, Mayuri; Liu, Xin; Thilaganathan, Nishan; Larina, Irina V.; Dickinson, Mary E.; West, Jennifer L.; Gibbons, Don L.; Liu, Diane D.; Kim, Min P.; Hicks, John M.; Wistuba, Ignacio I.; Hanash, Samir M.; Kurie, Jonathan M.The extracellular matrix of epithelial tumors undergoes structural remodeling during periods of uncontrolled growth, creating regional heterogeneity and torsional stress. How matrix integrity is maintained in the face of dynamic biophysical forces is largely undefined. Here we investigated the role of fibulin-2, a matrix glycoprotein that functions biomechanically as an inter-molecular clasp and thereby facilitates supra-molecular assembly. Fibulin-2 was abundant in the extracellular matrix of human lung adenocarcinomas and was highly expressed in tumor cell lines derived from mice that develop metastatic lung adenocarcinoma from co-expression of mutant K-ras and p53. Loss-offunction experiments in tumor cells revealed that fibulin-2 was required for tumor cells to grow and metastasize in syngeneic mice, a surprising finding given that other intra-tumoral cell types are known to secrete fibulin-2. However, tumor cells grew and metastasized equally well in Fbln2-null and -wildtype littermates, implying that malignant progression was dependent specifically upon tumor cellderived fibulin-2, which could not be offset by other cellular sources of fibulin-2. Fibulin-2 deficiency impaired the ability of tumor cells to migrate and invade in Boyden chambers, to create a stiff extracellular matrix in mice, to cross-link secreted collagen, and to adhere to collagen. We concludeItem Immobilization of Cell-Adhesive Laminin Peptides in Degradable PEGDA Hydrogels Influences Endothelial Cell Tubulogenesis(Mary Ann Liebert, Inc., 2013) Ali, Saniya; Saik, Jennifer E.; Gould, Dan J.; Dickinson, Mary E.; West, Jennifer L.Attachment, spreading, and organization of endothelial cells into tubule networks are mediated by interactions between cells in the extracellular microenvironment. Laminins are key extracellular matrix components and regulators of cell adhesion, migration, and proliferation. In this study, laminin-derived peptides were conjugated to poly(ethylene glycol) (PEG) monoacrylate and covalently incorporated into degradable PEG diacrylate (PEGDA) hydrogels to investigate the influence of these peptides on endothelial cellular adhesion and function in organizing into tubule networks. Degradable PEGDA hydrogels were synthesized by incorporating a matrix metalloproteinase (MMP)-sensitive peptide, GGGPQGIWGQGK (abbreviated PQ), into the polymer backbone. The secretion ofMMP-2 and MMP-9 by endothelial cells promotes polymer degradation and consequently cell migration. We demonstrate the formation of extensive networks of tubule-like structures by encapsulated human umbilical vein endothelial cells in hydrogels with immobilized synthetic peptides. The resulting structures were stabilized by pericyte precursor cells (10T1/2s) in vitro. During tubule formation and stabilization, extracellular matrix proteins such as collagen IV and laminin were deposited. Tubules formed in the matrix of metalloproteinase sensitive hydrogels were visualized from 7 days to 4 weeks in response to different combination of peptides. Moreover, hydrogels functionalized with laminin peptides and transplanted in a mouse cornea supported the ingrowth and attachment of endothelial cells to the hydrogel during angiogenesis. Results of this study illustrate the use of laminin-derived peptides as potential candidates for modification of biomaterials to support angiogenesis.Item Improved Angiogenesis in Response to Localized Delivery of Macrophage-Recruiting Molecules(Public Library of Science, 2015) Hsu, Chih-Wei; Poché, Ross A.; Saik, Jennifer E.; Ali, Saniya; Wang, Shang; Yosef, Nejla; Calderon, Gisele A.; Scott, Larry Jr.; Vadakkan, Tegy J.; Larina, Irina V.; West, Jennifer L.; Dickinson, Mary E.Successful engineering of complex organs requires improved methods to promote rapid and stable vascularization of artificial tissue scaffolds. Toward this goal, tissue engineering strategies utilize the release of pro-angiogenic growth factors, alone or in combination, from biomaterials to induce angiogenesis. In this study we have used intravital microscopy to define key, dynamic cellular changes induced by the release of pro-angiogenic factors from polyethylene glycol diacrylate hydrogels transplanted in vivo. Our data show robust macrophage recruitment when the potent and synergistic angiogenic factors, PDGFBB and FGF2 were used as compared with VEGF alone and intravital imaging suggested roles for macrophages in endothelial tip cell migration and anastomosis, as well as pericyte-like behavior. Further data from in vivo experiments show that delivery of CSF1 with VEGF can dramatically improve the poor angiogenic response seen with VEGF alone. These studies show that incorporating macrophage-recruiting factors into the design of pro-angiogenic biomaterial scaffolds is a key strategy likely to be necessary for stable vascularization and survival of implanted artificial tissues.Item Nanoshells in vivo imaging using two-photon excitation microscopy(2010) Gao, Liang; Dickinson, Mary E.This thesis describes the development and optical characterization of near infrared (NIR) gold nanoshells for the use as luminescent contrast agents for applications in small animal blood vessel imaging. Two types of gold-silica nanoshells excitable by NIR lasers are investigated: Type 1 nanoshells can be excited with a sub-mum NW laser, whereas Type 2 nanoshells can be excited with a NW laser in the micrometer range. Using NIR microscopy as an imaging platform, ex vivo and in vivo experiments are conducted to determine the efficacy of these nanoshells as suitable contrast agents. Specifically, individual particles of Type 1 nanoshells are successfully imaged and shown to provide bright optical contrast for blood vessel imaging both ex vivo and in vivo, while the Type 2 nanoshells are clearly imaged within the blood vessels ex vivo. These positive results suggest a promising possibility of developing a new class of contrast agents for deep tissue imaging and improving the imaging depth of NIR imaging techniques.Item Recapitulation and Modulation of the Cellular Architecture of a User-Chosen Cell of Interest Using Cell-Derived, Biomimetic Patterning(American Chemical Society, 2015) Slater, John H.; Culver, James C.; Long, Byron L.; Hu, Chenyue W.; Hu, Jingzhe; Birk, Taylor F.; Qutub, Amina A.; Dickinson, Mary E.; West, Jennifer L.Heterogeneity of cell populations can confound population-averaged measurements and obscure important findings or foster inaccurate conclusions. The ability to generate a homogeneous cell population, at least with respect to a chosen trait, could significantly aid basic biological research and development of high-throughput assays. Accordingly, we developed a high-resolution, image-based patterning strategy to produce arrays of single-cell patterns derived from the morphology or adhesion site arrangement of user-chosen cells of interest (COIs). Cells cultured on both cell-derived patterns displayed a cellular architecture defined by their morphology, adhesive state, cytoskeletal organization, and nuclear properties that quantitatively recapitulated the COIs that defined the patterns. Furthermore, slight modifications to pattern design allowed for suppression of specific actin stress fibers and direct modulation of adhesion site dynamics. This approach to patterning provides a strategy to produce a more homogeneous cell population, decouple the influences of cytoskeletal structure, adhesion dynamics, and intracellular tension on mechanotransduction-mediated processes, and a platform for high-throughput cellular assays.Item Tailoring vessel morphology in vivo(2012) Gould, Daniel Joseph; Dickinson, Mary E.Tissue engineering is a rapidly growing field which seeks to provide alternatives to organ transplantation in order to address the increasing need for transplantable tissues. One huge hurdle in this effort is the provision of thick tissues; this hurdle exists because currently there is no way to provide prevascularized or rapidly vascularizable scaffolds. To design thick, vascularized tissues, scaffolds are needed that can induce vessels which are similar to the microvasculature found in normal tissues. Angiogenic biomaterials are being developed to provide useful scaffolds to address this problem. In this thesis angiogenic and cell signaling and adhesion factors were incorporated into a biomimetic poly(ethylene glycol) (PEG) hydrogel system. The composition of these hydrogels was precisely tuned to induce the formation of differing vessel morphology. To sensitively measure induced microvascular morphology and to compare it to native microvessels in several tissues, this thesis developed an image-based tool for quantification of scale invariant and classical measures of vessel morphology. The tool displayed great utility in the comparison of native vessels and remodeling vessels in normal tissues. To utilize this tool to tune the vessel response in vivo , Flk1::myr-mCherry fluorescently labeled mice were implanted with Platelet Derived Growth Factor-BB (PDGF-BB) and basic Fibroblast Growth Factor (FGF-2) containing PEG-based hydrogels in a modified mouse corneal angiogenesis assay. Resulting vessels were imaged with confocal microscopy, analyzed with the image based tool created in this thesis to compare morphological differences between treatment groups, and used to create a linear relationship between space filling parameters and dose of growth factor release. Morphological parameters of native mouse tissue vessels were then compared to the linear fit to calculate the dose of growth factors needed to induce vessels similar in morphology to native vessels. Resulting induced vessels did match in morphology to the target vessels. Several other covalently bound signals were then analyzed in the assay and resulting morphology of vessels was compared in several studies which further highlighted the utility of the micropocket assay in conjunction with the image based tool for vessel morphological quantification. Finally, an alternative method to provide rapid vasculature to the constructs, which relied on pre-seeded hydrogels encapsulated endothelial cells was also developed and shown to allow anastamosis between induced host vessels and the implanted construct within 48 hours. These results indicate great promise in the rational design of synthetic, bioactive hydrogels, which can be used as a platform to study microvascular induction for regenerative medicine and angiogenesis research. Future applications of this research may help to develop therapeutic strategies to ameliorate human disease by replacing organs or correcting vessel morphology in the case of ischemic diseases and cancer.Item The NIH Somatic Cell Genome Editing program(Springer Nature, 2021) Saha, Krishanu; Sontheimer, Erik J.; Brooks, P.J.; Dwinell, Melinda R.; Gersbach, Charles A.; Liu, David R.; Murray, Stephen A.; Tsai, Shengdar Q.; Wilson, Ross C.; Anderson, Daniel G.; Asokan, Aravind; Banfield, Jillian F.; Bankiewicz, Krystof S.; Bao, Gang; Bulte, Jeff W.M.; Bursac, Nenad; Campbell, Jarryd M.; Carlson, Daniel F.; Chaikof, Elliot L.; Chen, Zheng-Yi; Cheng, R. Holland; Clark, Karl J.; Curiel, David T.; Dahlman, James E.; Deverman, Benjamin E.; Dickinson, Mary E.; Doudna, Jennifer A.; Ekker, Stephen C.; Emborg, Marina E.; Feng, Guoping; Freedman, Benjamin S.; Gamm, David M.; Gao, Guangping; Ghiran, Ionita C.; Glazer, Peter M.; Gong, Shaoqin; Heaney, Jason D.; Hennebold, Jon D.; Hinson, John T.; Khvorova, Anastasia; Kiani, Samira; Lagor, William R.; Lam, Kit S.; Leong, Kam W.; Levine, Jon E.; Lewis, Jennifer A.; Lutz, Cathleen M.; Ly, Danith H.; Maragh, Samantha; McCray, Paul B.; McDevitt, Todd C.; Mirochnitchenko, Oleg; Morizane, Ryuji; Murthy, Niren; Prather, Randall S.; Ronald, John A.; Roy, Subhojit; Roy, Sushmita; Sabbisetti, Venkata; Saltzman, W. Mark; Santangelo, Philip J.; Segal, David J.; Shimoyama, Mary; Skala, Melissa C.; Tarantal, Alice F.; Tilton, John C.; Truskey, George A.; Vandsburger, Moriel; Watts, Jonathan K.; Wells, Kevin D.; Wolfe, Scot A.; Xu, Qiaobing; Xue, Wen; Yi, Guohua; Zhou, JiangbingThe move from reading to writing the human genome offers new opportunities to improve human health. The United States National Institutes of Health (NIH) Somatic Cell Genome Editing (SCGE) Consortium aims to accelerate the development of safer and more-effective methods to edit the genomes of disease-relevant somatic cells in patients, even in tissues that are difficult to reach. Here we discuss the consortium’s plans to develop and benchmark approaches to induce and measure genome modifications, and to define downstream functional consequences of genome editing within human cells. Central to this effort is a rigorous and innovative approach that requires validation of the technology through third-party testing in small and large animals. New genome editors, delivery technologies and methods for tracking edited cells in vivo, as well as newly developed animal models and human biological systems, will be assembled—along with validated datasets—into an SCGE Toolkit, which will be disseminated widely to the biomedical research community. We visualize this toolkit—and the knowledge generated by its applications—as a means to accelerate the clinical development of new therapies for a wide range of conditions.