Title Classification and identification of central nervous system glia Title (croatian) Klasifikacija i identifikacija glijalnih stanica središnjeg živčanog sustava Author Marta Pongrac Mentor Jelena Ban (mentor) Committee member Miranda Mladinić Pejatović (predsjednik povjerenstva) Committee member Ivana Munitić (član povjerenstva) Granter University of Rijeka Defense date and country 2019-09-19, Croatia Scientific / art field, INTERDISCIPLINARY AREAS OF KNOWLEDGE Abstract Glia is a very heterogeneous cell population comprised of very different cells that work together to maintain central nervous system (CNS) homeostasis. Long believed role of glia being the acellular connective tissue has been overturned, and they have become focus of intense research. Due to the technological advances, new functions are being discovered, as well as interactions of glia with neurons and the glia between themselves. During CNS development, radial glia guide neuronal migration, NG2 receive neuronal inputs and inhibit axonal growth, oligodendrocytes myelinate axons, astrocytes form the blood-brain-barrier (BBB) and regulate optimal conditions, such as pH, ion gradient, neurotransmitter reuptake. Moreover, ependymal cells form cerebrospinal fluid (CSF) and protect CNS, while microglia remove unwanted cells. In pathological conditions, glia interact with immune system and release neurotrophic factors. However, many issues remain to be addressed, because identification and characterization of glia still represents a challenge. Glia differ in morphology, biochemistry and functions. They are most commonly identified by expressed molecules on cell membrane, cytoskeletal proteins or signal molecules, such as growth factors, neurotrophic factors, hormones or cytokines they release. Identification presents a problem because there is an insufficient amount of markers that can specifically identify a particular glial (sub)type because the markers are often co-expressed by several cell types of the nervous system. Co-expression and heterogeneity of glial (sub)types often lead to assignment of the same category. The aim of this work is to bring together the research conducted on CNS glia and to compare different opinions and findings throughout the history, critically remarking the research. This work focuses on characterization and identification of neuroglia types and pointing out the similarities and differences among them. Most commonly used immunostaining markers, for example, GFAP, S100β, Nestin, NG2 and Iba1 are analyzed with their advantages and weaknesses regarding specificity. As the glia are vital part of CNS in both healthy and pathological conditions, more research should be directed to them. Research should also involve humans and depict unique primate glia, with still unknown functions.
Abstract (croatian) Glija je vrlo heterogena populacija sastavljena od vrlo različitih stanica koje zajedno sudjeluju u održavanju homeostaze središnjeg živčanog sustava (SŽS). Dugo se smatralo da se radi o acelularnom vezivnom tkivu, dok je danas to gledište u potpunosti odbačeno te je sve više istraživanja usmjereno prema glijalnim stanicama. Zahvaljujući tehnološkom napretku, otkrivaju se nove posebitosti u funkciji tih stanica te njihovoj interakciji kako s neuronima, tako i međusobno. Tijekom razvoja SŽS, radijalne glije vode migraciju neurona, NG2 stanice primaju informacije od neurona i inhibiraju aksonalni rast, oligodendrociti formiraju mijelin, astrociti formiraju krvno-moždanu barijeru (KMB) i reguliraju optimalne uvjete poput pH, ionskog gradijenta, reapsorpcije neurotransmitera. Nadalje, ependimalne stanice formiraju cerebrospinalni fluid (CSF) i štite SŽS, a mikroglija uklanjaju neželjene stanice. U patološkim uvjetima glijalne stanice djeluju s imunosnim sustavom i otpuštaju neurotrofičke faktore. Međutim, mnogo još preostaje neobjašnjeno, a već i sama identifikacija i karakterizacija glija predstavljaju izazov. Glijalne stanice se razlikuju po morfologiji, biokemiji i funkcijama. Za njihovu identifikaciju se najčešće koriste eksprimirane molekule na staničnoj membrani, proteini citoskeleta ili signalne molekule poput faktora rasta, neurotrofičkih faktora, hormona i citokina koje otpuštaju. Identifikacija nailazi na probleme jer ne postoji dovoljno markera koji mogu sa sigurnošću odrediti (pod)tipove glija zbog toga što mnoge markere ko-eksprimiraju različite stanice živčanog sustava. Ko-ekspresija i heterogenost često vodi prema svrstavanju (pod)tipova glija u istu kategoriju. Cilj ovog rada je sakupiti istraživanja provedena na glijalnim stanicama SŽS i usporediti različite stavove i pronalaske kroz povijest uz kritički osvrt. Ovaj rad se usredotočuje na karakterizaciju i identifikaciju tipova glijalnih stanica te usporedbi međusobnih sličnosti i razlika. Označavanje glijalnih stanica pomoću antitijela, kao najpopularnija metoda identifikacije je analizirana prema korištenim markerima poput GFAP, S100β, Nestin, NG2, Iba1 i sl. te su navedene njihove prednosti i nedostatci. Kako su glije ključan dio središnjeg živčanog sustava u zdravim i patološkim uvjetima, više istraživanja treba biti usmjereno prema njima. Istraživanja bi se trebala proširiti i na ljude i opisati posebne vrste glija primata, još nepoznatih funkcija.
Keywords
Astrocytes
oligodendrocytes
microglia
ependymal cells
NG2 glia
Keywords (croatian)
Astrociti
oligodendrociti
mikroglija
ependimalne stanice
NG2 glija
Language english URN:NBN urn:nbn:hr:193:671863 Study programme Title: Biotechnology and drug research Type of resource Text File origin Born digital Access conditions Open access Terms of use Public note The experimental work has been conducted on equipment financed by the European Regional Development Fund (ERDF) within the project “Research Infrastructure for Campus-based Laboratories at University of Rijeka” (RC.2.2.06-0001), the Croatian Science Foundation (CSF/HRZZ) grant IP-2016-06-7060 and the financial support from the University of Rijeka (18.12.2.1.01, 18-258-6427 and 18-290-1463). Created on 2019-10-12 18:10:34
