Five million Americans are presently living with disability as a result of traumatic brain injury (TBI). The majority of TBI research focuses on the factors that influence the onset of pathology, while fewer studies have addressed the mechanisms that promote recovery. Cellular loss associated with TBI is significant barrier to overcome, and recent advancements in stem cell transplantation and cellular rejuvenation provide a potential therapy for recovery. However, the mechanisms that regulate stem cell functions are still ill defined, and even less is known how the functions are altered following TBI. The studies outlined in this proposal will examine a family of molecules, Ephrins and their receptors (Eph receptors), which have been implicated throughout the developing CNS. We have recently demonstrated that these molecules are also expressed in adult stem/progenitor cell, adult neuroblasts and in surrounding tissues. We hypothesize that ephrinB3 may ? function to arrest cell cycle and in turn promote post-mitotic differentiation. Furthermore, following injury the over expression of ephrinB3 and/or its receptors may limit the ability of endogenous stem/progenitor cell to proliferate. We will employ gene-targeted knockout mice to investigate their functions within the subventricular zone (SVZ).
Aim 1 of this application will investigate their function in regulating endogenous adult stem/progenitor cell proliferation in the SVZ, and whether the absence of ephrinB3 can alter cell cycle protein concentrations.
Aim 2 will employ an in vitro assay to examine the mechanisms of action for ephrinB3 and signaling pathways used to regulate cell cycle arrest.
Aim 3 will examine the role of ephrinB3 and its Eph receptor(s) in controlling cell proliferation following TBI. These studies will provide essential mechanistic information on the function of ephrinB3 and its receptor(s) to regulate stem/progenitor cell proliferation in the normal and injured brain, and could lead to therapeutic treatments to promote recovery in the chronically injured patient. ? ?
|Assis-Nascimento, Poincyane; Tsenkina, Yanina; Liebl, Daniel J (2018) EphB3 signaling induces cortical endothelial cell death and disrupts the blood-brain barrier after traumatic brain injury. Cell Death Dis 9:7|
|Dixon, Kirsty J; Turbic, Alisa; Turnley, Ann M et al. (2017) Explant Methodology for Analyzing Neuroblast Migration. Bio Protoc 7:|
|Dixon, Kirsty J; Mier, Jose; Gajavelli, Shyam et al. (2016) EphrinB3 restricts endogenous neural stem cell migration after traumatic brain injury. Stem Cell Res 17:504-513|
|Assis-Nascimento, Poincyane; Umland, Oliver; Cepero, Maria L et al. (2016) A flow cytometric approach to analyzing mature and progenitor endothelial cells following traumatic brain injury. J Neurosci Methods 263:57-67|
|Perez, Enmanuel J; Cepero, Maria L; Perez, Sebastian U et al. (2016) EphB3 signaling propagates synaptic dysfunction in the traumatic injured brain. Neurobiol Dis 94:73-84|
|Dixon, Kirsty J; Theus, Michelle H; Nelersa, Claudiu M et al. (2015) Endogenous neural stem/progenitor cells stabilize the cortical microenvironment after traumatic brain injury. J Neurotrauma 32:753-64|
|Theus, M H; Ricard, J; Glass, S J et al. (2014) EphrinB3 blocks EphB3 dependence receptor functions to prevent cell death following traumatic brain injury. Cell Death Dis 5:e1207|
|Baumann, Gisela; Travieso, Lissette; Liebl, Daniel J et al. (2013) Pronounced hypoxia in the subventricular zone following traumatic brain injury and the neural stem/progenitor cell response. Exp Biol Med (Maywood) 238:830-41|
|Nelersa, Claudiu M; Barreras, Henry; Runko, Erik et al. (2012) High-content analysis of proapoptotic EphA4 dependence receptor functions using small-molecule libraries. J Biomol Screen 17:785-95|
|Theus, Michelle H; Ricard, Jerome; Liebl, Daniel J (2012) Reproducible expansion and characterization of mouse neural stem/progenitor cells in adherent cultures derived from the adult subventricular zone. Curr Protoc Stem Cell Biol Chapter 2:Unit 2D.8|
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