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Cellular Bioengineering (Liver. Skin). Cell-Interactive Biomaterials. Micro/Nanosystems BioengineeringProfessor Moghe's current research activities are organized into three major thrust areas. (1) Lipoprotein Retentive Nanoscale Substrates for Treatment of Atherosclerosis Cardiovascular disease takes a staggering toll of casualties among adult Americans each year. Two of the significant vascular pathologies related to the abnormal accumulation of lipids are atherosclerosis and macrovascular disease. which claims a million lives each year globally. Much research has been directed at the molecular design of drugs to alleviate the disorders of lipid metabolism. However. such drugs fail to comprehensively treat lipoprotein transport and retention dynamics. particularly at peripheral vascular sites. Thus. a comprehensive approach to treating lipid-related vascular disease could involve use of molecules regulating lipid metabolism as well as molecules that are suitably lipoprotein-philic and serve as multifunctional carriers for processing lipoproteins in transit. Ultimately. such carriers could be engineered to (a) sequester lipoproteins from macromolecular depots such as proteoglycans that heighten atherogenic tendencies; (b) reduce lipoprotein oxidation (which leads to unregulated uptake of LDL by macrophages. transforming them into foam cells. the precursors to atherosclerosis); and (c) enhance lipoprotein transport and clearance of mildly oxidized lipoproteins (via macrophages. and the liver). However. to engineer such carriers. an understanding of the chemical and geometric determinants of lipoprotein-retentive carrier substrates is necessary. Through active collaborations with Professor Uhrich (Chemistry) and Professor Tomassone (Chemical and Biochemical Engineering). we are currently investigating the chemistry and nanoscale geometry of substrates with maximal LDL retentivity. As a competitive strategy for LDL retention. novel diffusible. nanoscale carriers will be designed. that can present GAG-mimetic chemistry and retain LDL with high affinity. (2) Biodynamic Ligand Nanointerfaces with Biomaterials For Wound Healing/Tissue Engineering Migration of epidermal cells such as keratinocytes is critical to efficient re-epithelialization of chronic wounds and bioartificial matrices used in the tissue engineering of skin. We hypothesize that the establishment of a highly biodynamic interface of ligands on polymer substrates can significantly enhance the activation of cell motility. We have recently filed a patent application for such an interface by displaying adhesion ligands (fibronectin and its fragments) at the surface of self-assembled nanoshells of degradable matrix molecules. and presenting it on differentially PEGylated polymeric materials. We expect that cell activation can be systematically promoted through such interfaces via two primary mechanisms: first. at certain PEG levels in the polymer substrate. the ligand-nanocarrier can be actively "remodeled" upon cell attachment; second. by designing the appropriate size of the nanocarrier and the chemistry of the minimally activating ligand fragment. the entire ligand-nanocarrier can be internalized within the cells. thus activating the cells through a parallel endocytic pathway. This study focuses on the study of the trafficking dynamics of ligand nanocarriers through multiphoton microscopy of quantum-dot encapsulated ligand-nanocarriers. The use of quantum dots with different emission wavelengths will allow us to discriminate between the trafficking behavior of different ligand fragments. Finally. we will elucidate the changes in intracellular signaling molecules upon activation through the ligand nanocarriers. The innovative components of this research are its focus on biodynamic nanoscale ligand substrates that can activate cells through enhanced "sampling dynamics" of ligands at the cell-ligand adhesive interface. which has direct relevance to the ultimate development of improved biomimetic materials technology. This project is a result of multidisciplinary collaborations with Profs. Joachim Kohn (Chemistry) and Richard Riman (Ceramics & Materials Eng). (3) Cytomimetic Materials for Cell Adhesion and Differentiation The identification of appropriate liver-specific biomolecular signals can greatly enhance the cell-specific signaling elicited by "biomimetic" substrates for applications in cell-based ex vivo bioreactors. hepatic tissue engineering. and studies of pharmacology and toxicology using cell-based devices. Most adhesive matrix ligands. however. generally promote growth of liver cells (hepatocytes) at the expense of hepatocellular differentiation. We are currently exploring approaches to systematically establish a new biopolymeric hepatocyte-supporting interface based on fragments of the cell-cell adhesion molecule. E-cadherin. Cadherins are ubiquitous adhesion molecules that can trigger intracellular signaling necessary for liver-specific differentiated gene expression. However. the cell functional determinants of cadherin microdisplay from polymer substrates are not currently understood. Cadherin-activation of cell differentiation is usually studied in systems with multicellular adhesion. due to which direct cadherin activation in individual cells cannot be decoupled from juxtacrine signaling caused by secondary cell-cell adhesion processes. Therefore. we are investigating the role of cadherin signaling on single-cell systems (using micropatterned ligands). as well as on multicellular systems (using cocultures and hepatocyte aggregates). In our single-cell studies. we utilize advances in microscale lithographic technology to create microstamped anchors for display of variable concentrations of E-cadherin chimeras from "discrete" biopolymeric islands of microscale dimensions. for binding to single hepatocytes. The study has one major objective. to study the effect of cadherin microdisplay on single cell adhesion and intracellular cytoskeletal activity (morphogenesis). and differentiated gene expression and signaling. We seek to identify a microdisplay regimen where cadherin (ligand) binding can cause intracellular cytoskeletal complexation and adhesion strengthening without significant overall cell morphogenesis. Furthermore. the effects of cadherin presentation are examined on upstream signaling of cadherin-activated pathways and downstream gene expression profiling of key transcription factors that may promote liver-specific differentiated functions. The outcomes of single-cell studies can potentially aid: the development of novel single hepatocyte cultures for diagnostic applications (cell-on-a-chip for pharmacology); and design of "cell-mimetic" substrates for cell transplantation. which are function inductive even under conditions of sparse cellularity. Our recent coculture studies of hepatocytes and E-cadherin transfected fibroblasts have shown that the progressive display of E-cadherins at the heterocellular interface can significantly improve hepatocellular function beyond the basal elevation of function due to mixed cultures. We are currently investigating the parameters that can maximize this effect using acellular cadherins displayed from microbeads and micropillars. in an effort to recapitulate the minimal functional determinants in the coculture system. Funding Sponsors: National Science Foundation. American Heart Association. Johnson & Johnson Discovery Award. Rutgers SROA Award. NIH Biotechnology Training Program. NIH NCRR Grant Selected PublicationsJohnson PA, Luk A, Demtchouk A, Patel H, Sung HJ, Treiser MD, Gordonov S, Sheihet L, Bolikal D, Kohn J, Moghe PV. (2009) Interplay of anionic charge, poly(ethylene glycol), and iodinated tyrosine incorporation within tyrosine-derived polycarbonates: Effects on vascular smooth muscle cell adhesion, proliferation, and motility. J Biomed Mater Res A. Jul 7. [Epub ahead of print] PMID: 19585568 Liu E, Treiser MD, Patel H, Sung HJ, Roskov KE, Kohn J, Becker ML, Moghe PV. (2009) Moore RN, Moghe PV. (2009) Expedited growth factor-mediated specification of human embryonic stem cells toward the hepatic lineage. Stem Cell Res. May 7. [Epub ahead of print] Plourde NM, Kortagere S, Welsh W, Moghe PV. (2009) Structure-Activity Relations of Nanolipoblockers with the Atherogenic Domain of Human Macrophage Scavenger Receptor A. Biomacromolecules. 10(6):1381-91. Briggs T, Treiser MD, Holmes PF, Kohn J, Moghe PV, Arinzeh TL. (2008)Osteogenic differentiation of human mesenchymal stem cells on poly(ethylene glycol)-variant biomaterials. J Biomed Mater Res A. Dec 18. [Epub ahead of print] Sung HJ, Chandra P, Treiser MD, Liu E, Iovine CP, Moghe PV, Kohn J. (2008) Synthetic polymeric substrates as potent pro-oxidant versus anti-oxidant regulators of cytoskeletal remodeling and cell apoptosis. J Cell Physiol. 218(3):549-57. Sharma RI, Shreiber DI, Moghe PV. (2008) Nanoscale variation of bioadhesive substrates as a tool for engineering of cell matrix assembly. Tissue Eng Part A. 14(7):1237-50. Moore RN, Dasgupta A, Rajaei N, Yarmush ML, Toner M, Larue L, Moghe PV. (2008) Enhanced differentiation of embryonic stem cells using co-cultivation with hepatocytes. Biotechnol Bioeng. 101(6):1332-43. Iverson N, Plourde N, Chnari E, Nackman GB, Moghe PV. (2008) Convergence of nanotechnology and cardiovascular medicine : progress and emerging prospects. BioDrugs. 22(1):1-10. Review. Wang J, Plourde NM, Iverson N, Moghe PV, Uhrich KE. (2007) Nanoscale amphiphilic macromolecules as lipoprotein inhibitors: the role of charge and architecture. Int J Nanomedicine. 2(4):697-705. Treiser MD, Liu E, Dubin RA, Sung HJ, Kohn J, Moghe PV. (2007) Profiling cell-biomaterial interactions via cell-based fluororeporter imaging. Biotechniques. 43(3):361-6, 368. Liu E, Treiser MD, Johnson PA, Patel P, Rege A, Kohn J, Moghe PV. (2007) Quantitative biorelevant profiling of material microstructure within 3D porous scaffolds via multiphoton fluorescence microscopy. J Biomed Mater Res B Appl Biomater. 82(2):284-97. Pereira M, Sharma RI, Penkala R, Gentzel TA, Schwarzbauer JE, Moghe PV. (2007) Engineered cell-adhesive nanoparticles nucleate extracellular matrix assembly. Tissue Eng. 13(3):567-78. Semler EJ, Ranucci CS, Moghe PV. (2006) Tissue assembly guided via substrate biophysics: applications to hepatocellular engineering. Adv Biochem Eng Biotechnol. 102:1-46. Review. Bae YH, Johnson PA, Florek CA, Kohn J, Moghe PV. (2006) Minute changes in composition of polymer substrates produce amplified differences in cell adhesion and motility via optimal ligand conditioning. Acta Biomater. 2(5):473-82. Chnari E, Nikitczuk JS, Wang J, Uhrich KE, Moghe PV. (2006) Engineered polymeric nanoparticles for receptor-targeted blockage of oxidized low density lipoprotein uptake and atherogenesis in macrophages. Biomacromolecules. 7(6):1796-805. Chnari E. Nikitczuk JS. Uhrich KE. Moghe PV. (2006) Nanoscale anionic macromolecules can inhibit cellular uptake of differentially oxidized LDL. Biomacromolecules. 7(2):597-603. Brieva. T.A. and Moghe. P.V. (2004). Exogenous cadherin microdisplay can interfere with endogenous signaling and reprogram gene expression in cultured hepatocytes. Biotechnol. Bioeng. 85:359-369. Sharma. R.I.. Kohn. J. and Moghe. P.V. (2004). PEG accelerates cell motility on protein-based PEG-polycarbonate substrates: A mechanism for cell-guided ligand remodeling Journal of Biomedical Materials Research 69A: 114-123. Brieva. T. and Moghe. P.V. (2004). Engineering hepatocyte differentiation-proliferation balance by cadherin micropresentation tissue engineering 10:553-564. |
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