DOCSLIB.ORG

Scaffolds with Oriented Microchannels for Angioneural Regenerative Engineering By

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Scaffolds with Oriented Microchannels for Angioneural Regenerative Engineering By Scaffolds with Oriented Microchannels for Angioneural Regenerative Engineering A Thesis Submitted to the Faculty of Drexel University by Aybike Saglam in partial fulfillment of the requirements for the degree of Master of Science in Biomedical Engineering December 2010 To my father… iii iv ACKNOWLEDGMENTS It is very difficult to express how grateful I am to the people who contributed to this project. First of all, I want to thank to my committee members: Dr. Peter I. Lelkes, Dr. Philip Lazarovici, Dr. Anat Perets Katsir and Dr. Fred Allen. This thesis would have been impossible without all of you. Dr. Lelkes was a great advisor and mentor who was a big influence in my academic life. Dr. Perets was an amazing advisor and friend with constant optimism and encouragement. Dr. Lazarovici was an inspiration for good academic character and integrity and I hope to be as good an academian some day. Dr. Allen was a particularly positive source of encouragement in the beginning of my degree. Special thanks to Dr. Onaral, Dean of Biomedical Engineering, Science, and Health Systems, for serving as such a positive and tenacious role model for me throughout my degree. Thanks to many individuals and groups who have helped me considerably along the way: Dr. Itzhak Fisher,Dr. Gianluca Gallo, and to their laboratory members for their help on primary neuron extraction and culture, particularly Dr. Katherine Kollins; Dr. J. Yasha Kresh and Anant for letting me use the rheometer even for extended hours; Dr. Yvonne Mueller for her help on Fluorescence Activated Cell Sorting technique; and Dr. Qingwei Zhang and Gozde Senel for their help on Scanning Electron Microscopy. Thanks, too, to my friends and labmates: Mie was a great friend, advisor, mentor, roommate, classmate, and labmate; Greg, Diane and Leko who were never too busy v to help me; Adam who was personally involved in some of my experiments and designed the controlled freeze-drying machine with Ho-Lung Li according to Dr. Peret’s directives; my “sisters,” Gozde, Seda and particularly Asli made me feel at home; our program manager, Susan; our program coordinator, Tantri; Dr. Har-el was a source of advice and support; labmates Mike, Collin, Patrick, Gaurav, Sean, Jingjia, Tracy, Jessica, and Anna; and finally, Paul for fixing the lyophilization machine. Thanks to many institutions and programs on campus for their logistical support: the Biomed office, specifically Aylin, Natalia, Danielle and Lisa; and the ISSS office, especially to Adrienne. Finally, but not least, to my family and friends to whom I am grateful for their support. vi TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................................................................................. iv TABLE OF CONTENTS ............................................................................................................................................. vi List of Figures ........................................................................................................................................................... vii ABSTRACT ................................................................................................................................................................ viii INTRODUCTION ......................................................................................................................................................... 1 .1 Overall goal & hypothesis ............................................................................................................................... 2 .2 Aims of the thesis ............................................................................................................................................... 3 .3 Definitions ............................................................................................................................................................ 4 .4 Rationale .............................................................................................................................................................. 4 BACKGROUND ............................................................................................................................................................ 8 .1 Past & current tissue engineering strategies for SCI ............................................................................. 8 .2 Spinal cord organization ............................................................................................................................... 10 .3 Spinal cord injury ............................................................................................................................................ 11 .4 Overview on Scaffolds for SCI ...................................................................................................................... 12 .5 Hydrogels for engineered scaffolds ........................................................................................................... 16 .6 Freeze­drying techniques ............................................................................................................................. 16 .7 The effect of pore diameter on axon extension and ECM secretion ................................................ 19 .8 Angiogenesis & vasculogenesis: .................................................................................................................. 20 .9 Neuritogenesis .................................................................................................................................................. 22 .10 Neurovascular crosstalk ................................................................................................................................ 24 .10.1 Interactions between nervous & vascular systems: ................................................................................. 24 .11 Cross­talk between neurons and ECs ..................................................................................................... 25 .11.1 Angiogenic factors’ effects on the nervous system: .................................................................................. 27 .11.2 Neurogenic factors’ effects on the vascular system .................................................................................. 28 MATERIALS AND METHODS ................................................................................................................................ 30 .1 Preparation of genipin crosslinked gelatin polymer (GCG) .............................................................. 30 .2 Scaffold production by regular and controlled freeze­drying .......................................................... 30 .3 Measurements of mechanical properties of the scaffold .................................................................... 33 .4 In­vitro degradation of the GCG­CFDSs ..................................................................................................... 33 .5 Cells ...................................................................................................................................................................... 34 .6 Cell proliferation ............................................................................................................................................. 37 .7 Fluorescence activated cell sorting (FACS) ............................................................................................. 37 .8 Endothelial cell labeling ................................................................................................................................ 38 .9 Populating the scaffold with cells and treatment with angioneurins ............................................ 39 .10 Confocal Microscopy ....................................................................................................................................... 39 .11 Scanning Electron Microscopy .................................................................................................................... 40 .12 Statistics .............................................................................................................................................................. 40 RESULTS & DISCUSSION ........................................................................................................................................ 41 .1 The morphology of the scaffolds ................................................................................................................ 41 .2 The mechanical properties of the scaffolds ............................................................................................ 43 .3 The degradability of the GCG­CFDS in the serum .................................................................................. 44 .4 Biocompatibility of the GCG­CFDS for homogeneous cell populations .......................................... 45 .5 Biocompatibility of the GCG­CFDS for heterogeneous cell populations ........................................ 49 SUMMARY .................................................................................................................................................................. 53 CONCLUSION& FUTURE WORK........................................................................................................................... 56 LIST of REFERENCES .............................................................................................................................................
Load more

Recommended publications
  • Plasma Membrane-Derived Microvesicles Released from Tip Endothelial Cells During Vascular Sprouting
    CORE Metadata, citation and similar papers at core.ac.uk Provided by Springer - Publisher Connector Angiogenesis (2012) 15:761–769 DOI 10.1007/s10456-012-9292-y BRIEF COMMUNICATION Plasma membrane-derived microvesicles released from tip endothelial cells during vascular sprouting Daniela Virgintino • Marco Rizzi • Mariella Errede • Maurizio Strippoli • Francesco Girolamo • Mirella Bertossi • Luisa Roncali Received: 9 May 2012 / Accepted: 18 July 2012 / Published online: 11 August 2012 Ó The Author(s) 2012. This article is published with open access at Springerlink.com Abstract During human foetal brain vascularization, Keywords Neuroangiogenesis Á Tip cells Á Endothelial activated CD31?/CD105? endothelial cells are character- filopodia Á Plasma membrane-derived microvesicles Á ized by the emission of filopodial processes which also Human foetal brain Á Immunofluorescence confocal decorate the advancing tip of the vascular sprout. Together microscopy with filopodia, both the markers also reveal a number of plasma membrane-derived microvesicles (MVs) which are concentrated around the tip cell tuft of processes. At this Introduction site, MVs appear in tight contact with endothelial filopodia and follow these long processes, advancing into the sur- Exosomes and other plasma membrane-derived vesicles, rounding neuropil to a possible cell target. These obser- known as ectosomes, shed vesicles, or microvesicles (MV), vations suggest that, like shedding vesicles of many other are secreted by many different cell types and are thought to cell types that deliver signalling molecules and play a role play important roles in cell–cell communication by in cell-to-cell communication, MVs sent out from endo- releasing various active molecules including signalling thelial tip cells could be involved in tip cell guidance and/ molecules, mRNAs, and miRNAs, in both physiological or act on target cells, regulating cell-to-cell mutual recog- and pathological processes.
    [Show full text]
  • Proteomic Identification of Neurotrophins in the Eutopic Endometrium of Women with Endometriosis Aimee S
    Proteomic identification of neurotrophins in the eutopic endometrium of women with endometriosis Aimee S. Browne, Emory University Jie Yu, Wake Forest University Ruo-Pan Huang, Emory University Antonio M.C. Francisco, Wake Forest University Neil Sidell, Emory University W Robert Taylor, Emory University Journal Title: Fertility and Sterility Volume: Volume 98, Number 3 Publisher: Elsevier | 2012-09-01, Pages 713-719 Type of Work: Article | Post-print: After Peer Review Publisher DOI: 10.1016/j.fertnstert.2012.05.027 Permanent URL: https://pid.emory.edu/ark:/25593/s9fwb Final published version: http://dx.doi.org/10.1016/j.fertnstert.2012.05.027 Copyright information: © 2012 by American Society for Reproductive Medicine. This is an Open Access work distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (http://creativecommons.org/licenses/by-nc-nd/4.0/). Accessed September 30, 2021 1:42 AM EDT NIH Public Access Author Manuscript Fertil Steril. Author manuscript; available in PMC 2013 September 01. NIH-PA Author ManuscriptPublished NIH-PA Author Manuscript in final edited NIH-PA Author Manuscript form as: Fertil Steril. 2012 September ; 98(3): 713–719. doi:10.1016/j.fertnstert.2012.05.027. Proteomic identification of neurotrophins in the eutopic endometrium of women with endometriosis Aimee S. Browne, MD, MSc1, Jie Yu, MD, MSc1,2, Ruo-Pan Huang, MD, PhD1,3, Antônio M. C. Francisco, MD2,4, Neil Sidell, PhD1, and Robert N. Taylor, MD, PhD1,2,* 1Department of Gynecology and Obstetrics,
    [Show full text]
  • Epithelial Cell Line Derived from Endometriotic Lesion Mimics Macrophage Nervous Mechanism of Pain Generation on Proteome and Metabolome Levels
    biomolecules Article Epithelial Cell Line Derived from Endometriotic Lesion Mimics Macrophage Nervous Mechanism of Pain Generation on Proteome and Metabolome Levels Benjamin Neuditschko 1,2,† , Marlene Leibetseder 1,† , Julia Brunmair 1 , Gerhard Hagn 1 , Lukas Skos 1, Marlene C. Gerner 3 , Samuel M. Meier-Menches 1,2,4 , Iveta Yotova 5 and Christopher Gerner 1,4,* 1 Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria; [email protected] (B.N.); [email protected] (M.L.); [email protected] (J.B.); [email protected] (G.H.); [email protected] (L.S.); [email protected] (S.M.M.-M.) 2 Department of Inorganic Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Straße 42, 1090 Vienna, Austria 3 Division of Biomedical Science, University of Applied Sciences, FH Campus Wien, Favoritenstraße 226, 1100 Vienna, Austria; [email protected] 4 Joint Metabolome Facility, Faculty of Chemistry, University of Vienna, Waehringer Straße 38, 1090 Vienna, Austria 5 Department of Obstetrics and Gynaecology, Medical University of Vienna, Spitalgasse 23, 1090 Vienna, Austria; [email protected] Citation: Neuditschko, B.; * Correspondence: [email protected] Leibetseder, M.; Brunmair, J.; Hagn, † Authors contributed equally. G.; Skos, L.; Gerner, M.C.; Meier-Menches, S.M.; Yotova, I.; Abstract: Endometriosis is a benign disease affecting one in ten women of reproductive age world- Gerner, C. Epithelial Cell Line wide. Although the pain level is not correlated to the extent of the disease, it is still one of the Derived from Endometriotic Lesion cardinal symptoms strongly affecting the patients’ quality of life.
    [Show full text]
  • A Therapeutic Approach for Senile Dementias: Neuroangiogenesis Charles T
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by University of Kentucky University of Kentucky UKnowledge Microbiology, Immunology, and Molecular Microbiology, Immunology, and Molecular Genetics Faculty Publications Genetics 2015 A Therapeutic Approach for Senile Dementias: Neuroangiogenesis Charles T. Ambrose University of Kentucky, [email protected] Click here to let us know how access to this document benefits oy u. Follow this and additional works at: https://uknowledge.uky.edu/microbio_facpub Part of the Geriatrics Commons, Molecular Genetics Commons, and the Neurology Commons Repository Citation Ambrose, Charles T., "A Therapeutic Approach for Senile Dementias: Neuroangiogenesis" (2015). Microbiology, Immunology, and Molecular Genetics Faculty Publications. 110. https://uknowledge.uky.edu/microbio_facpub/110 This Article is brought to you for free and open access by the Microbiology, Immunology, and Molecular Genetics at UKnowledge. It has been accepted for inclusion in Microbiology, Immunology, and Molecular Genetics Faculty Publications by an authorized administrator of UKnowledge. For more information, please contact [email protected]. A Therapeutic Approach for Senile Dementias: Neuroangiogenesis Notes/Citation Information Published in Journal of Alzheimer's Disease, v. 43, no. 1, p. 1-17. © 2015 – IOS Press and the author The opc yright holders have granted the permission for posting the article here. The document available for download is the author's post-peer-review final draft of the ra ticle. The final publication is available at IOS Press through https://doi.org/10.3233/JAD-140498. Digital Object Identifier (DOI) https://doi.org/10.3233/JAD-140498 This article is available at UKnowledge: https://uknowledge.uky.edu/microbio_facpub/110 ABSTRACT (234 words) Alzheimer’s disease (AD) and related senile dementias (SDs) represent a growing medical and economic crisis in this country.
    [Show full text]
  • Villainous Role of Estrogen in Macrophage-Nerve Interaction In
    Liang et al. Reproductive Biology and Endocrinology (2018) 16:122 https://doi.org/10.1186/s12958-018-0441-z REVIEW Open Access Villainous role of estrogen in macrophage- nerve interaction in endometriosis Yanchun Liang1, Hongyu Xie2, Jinjie Wu2, Duo Liu1 and Shuzhong Yao1* Abstract Endometriosis is a complex and heterogeneous disorder with unknown etiology. Dysregulation of macrophages and innervation are important factors influencing the pathogenesis of endometriosis-associated pain. It is known to be an estrogen-dependent disease, estrogen can promote secretion of chemokines from peripheral nerves, enhancing the recruitment and polarization of macrophages in endometriotic tissue. Macrophages have a role in the expression of multiple nerve growth factors (NGF), which mediates the imbalance of neurogenesis in an estrogen-dependent manner. Under the influence of estrogen, co-existence of macrophages and nerves induces an innovative neuro-immune communication. Persistent stimulation by inflammatory cytokines from macrophages on nociceptors of peripheral nerves aggravates neuroinflammation through the release of inflammatory neurotransmitters. This neuro-immune interaction regulated by estrogen sensitizes peripheral nerves, leading to neuropathic pain in endometriosis. The aim of this review is to highlight the significance of estrogen in the interaction between macrophages and nerve fibers, and to suggest a potentially valuable therapeutic target for endometriosis-associated pain. Keywords: Estrogen, Macrophage, Nerve fiber, Neuroinflammation, Endometriosis Introduction the aberrant distribution of nerves, impairment of Endometriosis is a common gynecological disorder, which immune microenvironment in the peritoneal cavity induces is defined as the presence of the endometrial-like tissue inflammation which can also mediate endometriosis-as- outside the uterine cavity [1]. This chronic inflammatory sociated pain [8].
    [Show full text]
  • Embryonic Periventricular Endothelial Cells Demonstrate a Unique Pro
    www.nature.com/scientificreports OPEN Embryonic periventricular endothelial cells demonstrate a unique pro‑neurodevelopment and anti‑infammatory gene signature Franciele Cristina Kipper1,5,7, Cleide Angolano2,5,7, Ravi Vissapragada1,4, Mauricio A. Contreras3, Justin Moore1,7, Manoj Bhasin6, Christiane Ferran2,3,5,7,8 & Ajith J. Thomas1,5,7,8* Brain embryonic periventricular endothelial cells (PVEC) crosstalk with neural progenitor cells (NPC) promoting mutual proliferation, formation of tubular‑like structures in the former and maintenance of stemness in the latter. To better characterize this interaction, we conducted a comparative transcriptome analysis of mouse PVEC vs. adult brain endothelial cells (ABEC) in mono‑culture or NPC co‑culture. We identifed > 6000 diferentially expressed genes (DEG), regardless of culture condition. PVEC exhibited a 30‑fold greater response to NPC than ABEC (411 vs. 13 DEG). Gene Ontology (GO) analysis of DEG that were higher or lower in PVEC vs. ABEC identifed “Nervous system development” and “Response to Stress” as the top signifcantly diferent biological process, respectively. Enrichment in canonical pathways included HIF1A, FGF/stemness, WNT signaling, interferon signaling and complement. Solute carriers (SLC) and ABC transporters represented an important subset of DEG, underscoring PVEC’s implication in blood–brain barrier formation and maintenance of nutrient‑rich/ non‑toxic environment. Our work characterizes the gene signature of PVEC and their important partnership with NPC, underpinning their unique role in maintaining a healthy neurovascular niche, and in supporting brain development. This information may pave the way for additional studies to explore their therapeutic potential in neuro‑degenerative diseases, such as Alzheimer’s and Parkinson’s disease.
    [Show full text]
  • Exosomes As Biomarkers for Female Reproductive Diseases Diagnosis and Therapy
    International Journal of Molecular Sciences Review Exosomes as Biomarkers for Female Reproductive Diseases Diagnosis and Therapy Sahar Esfandyari 1,2,†, Hoda Elkafas 1,3,† , Rishi Man Chugh 1,4, Hang-soo Park 5 , Antonia Navarro 5 and Ayman Al-Hendy 5,* 1 Department of Surgery, University of Illinois at Chicago, Chicago, IL 60612, USA; [email protected] (S.E.); [email protected] (H.E.); [email protected] (R.M.C.) 2 Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA 3 Department of Pharmacology and Toxicology, Egyptian Drug Authority (EDA) Formally, (NODCAR), Cairo 35521, Egypt 4 Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, KS 66160, USA 5 Department of Obstetrics and Gynecology, University of Chicago, Chicago, IL 60637, USA; [email protected] (H.-s.P.); [email protected] (A.N.) * Correspondence: [email protected]; Tel.: +1-773-832-0742 † These authors equally contributed in this work. Abstract: Cell–cell communication is an essential mechanism for the maintenance and development of various organs, including the female reproductive system. Today, it is well-known that the function of the female reproductive system and successful pregnancy are related to appropriate follicular growth, oogenesis, implantation, embryo development, and proper fertilization, dependent on the main regulators of cellular crosstalk, exosomes. During exosome synthesis, selective packaging of different factors into these vesicles happens within the originating cells. Therefore, exosomes Citation: Esfandyari, S.; Elkafas, H.; contain both genetic and proteomic data that could be applied as biomarkers or therapeutic targets Chugh, R.M.; Park, H.-s.; Navarro, A.; in pregnancy-associated disorders or placental functions.
    [Show full text]
  • Pain Related Genes in Endometriosis: a Meta-Analysis
    COPYRIGHT AND USE OF THIS THESIS This thesis must be used in accordance with the provisions of the Copyright Act 1968. Reproduction of material protected by copyright may be an infringement of copyright and copyright owners may be entitled to take legal action against persons who infringe their copyright. Section 51 (2) of the Copyright Act permits an authorized officer of a university library or archives to provide a copy (by communication or otherwise) of an unpublished thesis kept in the library or archives, to a person who satisfies the authorized officer that he or she requires the reproduction for the purposes of research or study. The Copyright Act grants the creator of a work a number of moral rights, specifically the right of attribution, the right against false attribution and the right of integrity. You may infringe the author’s moral rights if you: - fail to acknowledge the author of this thesis if you quote sections from the work - attribute this thesis to another author - subject this thesis to derogatory treatment which may prejudice the author’s reputation For further information contact the University’s Copyright Service. sydney.edu.au/copyright Pain related genes in endometriosis: A meta-analysis by Manika Saxena A thesis submitted to the Sydney Medical School in fulfilment of the requirement for the degree of Master of Philosophy in Science 2015 Queen Elizabeth II Research Institute for Mothers and Infants Department of Obstetrics, Gynaecology and Neonatology Sydney Medical School The University of Sydney, NSW, 2006 Australia © Manika Saxena, 2015 Declaration I, Manika Saxena hereby declare that the contents of this thesis consist of original work carried out by the author unless otherwise stated and duly acknowledged.
    [Show full text]
  • Potential Drug Candidates to Treat TRPC6 Channel Deficiencies in The
    cells Review Potential Drug Candidates to Treat TRPC6 Channel Deficiencies in the Pathophysiology of Alzheimer’s Disease and Brain Ischemia Veronika Prikhodko 1,2,3, Daria Chernyuk 1 , Yurii Sysoev 1,2,3,4, Nikita Zernov 1, Sergey Okovityi 2,3 and Elena Popugaeva 1,* 1 Laboratory of Molecular Neurodegeneration, Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia; [email protected] (V.P.); [email protected] (D.C.); [email protected] (Y.S.); [email protected] (N.Z.) 2 Department of Pharmacology and Clinical Pharmacology, Saint Petersburg State Chemical Pharmaceutical University, 197022 St. Petersburg, Russia; [email protected] 3 N.P. Bechtereva Institute of the Human Brain of the Russian Academy of Sciences, 197376 St. Petersburg, Russia 4 Institute of Translational Biomedicine, Saint Petersburg State University, 199034 St. Petersburg, Russia * Correspondence: [email protected] Received: 31 August 2020; Accepted: 20 October 2020; Published: 24 October 2020 Abstract: Alzheimer’s disease and cerebral ischemia are among the many causative neurodegenerative diseases that lead to disabilities in the middle-aged and elderly population. There are no effective disease-preventing therapies for these pathologies. Recent in vitro and in vivo studies have revealed the TRPC6 channel to be a promising molecular target for the development of neuroprotective agents. TRPC6 channel is a non-selective cation plasma membrane channel that is permeable to Ca2+. Its Ca2+-dependent pharmacological effect is associated with the stabilization and protection of excitatory synapses. Downregulation as well as upregulation of TRPC6 channel functions have been observed in Alzheimer’s disease and brain ischemia models.
    [Show full text]
  • 760 Ex Vivo Gene Therapy: Transplantation of Neurotrophic
    [Frontiers in Bioscience 11, 760-775, January 1, 2006] Ex vivo gene therapy: transplantation of neurotrophic factor-secreting cells for cerebral ischemia Takao Yasuhara 1, 2, Cesario V. Borlongan 2, 3, and Isao Date 1 1 Department of Neurological Surgery, Okayama University Graduate School of Medicine and Dentistry, 2-5-1, Shikata-cho, Okayama, 700-8558, Japan, 2Department of Neurology, Medical College of Georgia, 1120, 15th street, BI-3080, Augusta, GA, 30912, 3 Research and Affiliations Service Line, Augusta VA Medical Center, Augusta, GA 30912 TABLE OF CONTENTS 1. Abstract 2. Introduction 3. Strategy for cerebral ischemia using neurotrophic factor 3.1. Neurotrophic factors and stroke 3.2. Protective and regenerative properties of neurotrophic factors in stroke 3.3. Neurotrophic factor delivery 3.3.1. Surgical route of neurotrophic factor delivery 3.3.2. Protein manipulation, and in vivo and ex vivo gene manipulation of neurotrophic factors 3.3.3. Timing of neurotrophic factor delivery 3.4. Ex vivo gene therapy 3.4.1. Encapsulated cell transplantation 3.4.2. Neurotrophic factor-secreting stem cell transplantation 4. Perspective 5. Acknowledgements 6. References 1. ABSTRACT 2. INTRODUCTION Expressions of various neurotrophic factors or Regenerative medicine has been explored in the their receptors fluctuate after stroke, which in part regenerative organs such as skin, blood (1) and liver (2) or prompted investigations into the efficacy of neurotrophic in the ischemia-tolerant organs such as kidney (2) and factors as treatment modality for stroke. The methods to cornea. Heart and brain are considered as non-regenerative deliver neurotrophic factors into the brain can be and ischemia-intolerant organs.
    [Show full text]
  • Tunneling Nanotubes Evoke Pericyte/Endothelial Communication
    Errede et al. Fluids Barriers CNS (2018) 15:28 https://doi.org/10.1186/s12987-018-0114-5 Fluids and Barriers of the CNS RESEARCH Open Access Tunneling nanotubes evoke pericyte/ endothelial communication during normal and tumoral angiogenesis Mariella Errede1†, Domenica Mangieri2†, Giovanna Longo3, Francesco Girolamo1, Ignazio de Trizio1,4, Antonella Vimercati5, Gabriella Serio6, Karl Frei7, Roberto Perris8 and Daniela Virgintino1* Abstract Background: Nanotubular structures, denoted tunneling nanotubes (TNTs) have been described in recent times as involved in cell-to-cell communication between distant cells. Nevertheless, TNT-like, long flopodial processes had already been described in the last century as connecting facing, growing microvessels during the process of cerebral cortex vascularization and collateralization. Here we have investigated the possible presence and the cellular origin of TNTs during normal brain vascularization and also in highly vascularized brain tumors. Methods: We searched for TNTs by high-resolution immunofuorescence confocal microscopy, applied to the analy- sis of 20-µm, thick sections from lightly fxed, unembedded samples of both developing cerebral cortex and human glioblastoma (GB), immunolabeled for endothelial, pericyte, and astrocyte markers, and vessel basal lamina molecules. Results: The results revealed the existence of pericyte-derived TNTs, labeled by proteoglycan NG2/CSPG4 and CD146. In agreement with the described heterogeneity of these nanostructures, ultra-long (> 300 µm) and very thin (< 0.8 µm) TNTs were observed to bridge the gap between the wall of distant vessels, or were detected as short (< 300 µm) bridging cables connecting a vessel sprout with its facing vessel or two apposed vessel sprouts. The peri- cyte origin of TNTs ex vivo in fetal cortex and GB was confrmed by in vitro analysis of brain pericytes, which were able to form and remained connected by typical TNT structures.
    [Show full text]
  • Differential Expression of CD31 and Von Willebrand Factor On
    brain sciences Article Differential Expression of CD31 and Von Willebrand Factor on Endothelial Cells in Different Regions of the Human Brain: Potential Implications for Cerebral Malaria Pathogenesis Smart Ikechukwu Mbagwu 1,2,* and Luis Filgueira 1,* 1 Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, 1700 Fribourg, Switzerland 2 Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, 435101 Nnewi Campus, Nigeria * Correspondence: [email protected] (S.I.M.); luis.fi[email protected] (L.F.) Received: 12 November 2019; Accepted: 3 January 2020; Published: 6 January 2020 Abstract: Cerebral microvascular endothelial cells (CMVECs) line the vascular system of the brain and are the chief cells in the formation and function of the blood brain barrier (BBB). These cells are heterogeneous along the cerebral vasculature and any dysfunctional state in these cells can result in a local loss of function of the BBB in any region of the brain. There is currently no report on the distribution and variation of the CMVECs in different brain regions in humans. This study investigated microcirculation in the adult human brain by the characterization of the expression pattern of brain endothelial cell markers in different brain regions. Five different brain regions consisting of the visual cortex, the hippocampus, the precentral gyrus, the postcentral gyrus, and the rhinal cortex obtained from three normal adult human brain specimens were studied and analyzed for the expression of the endothelial cell markers: cluster of differentiation 31 (CD31) and von-Willebrand-Factor (vWF) through immunohistochemistry. We observed differences in the expression pattern of CD31 and vWF between the gray matter and the white matter in the brain regions.
    [Show full text]