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Team B³. Breaking through the Blood-Brain Barrier. Sakib Adnan Regina Borsellino Alice He Somdutta Mukherjee Victor Peng Karthya Potti Kelly Shih Janina Vaitkus Victor Wang Rani Woo Robert Zhang Adam Zuber. Mentor: Dr. Helim Aranda -Espinoza Librarian: Ms. Joscelyn Langholt.
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Team B³ Breaking through the Blood-Brain Barrier Sakib Adnan Regina Borsellino Alice He SomduttaMukherjee Victor Peng KarthyaPotti Kelly Shih JaninaVaitkus Victor Wang Rani Woo Robert Zhang Adam Zuber Mentor: Dr. HelimAranda-Espinoza Librarian: Ms. JoscelynLangholt
PROBLEM • The blood-brain barrier (BBB) does not allow drugs that treat neurological diseases, such as Alzheimer’s Disease, to cross from the bloodstream into the brain. • These diseases go untreated and become progressively worse.
PURPOSE • To use the body’s own immune system as a method of transporting drugs across the blood-brain barrier • Filomicelles as a vehicle for drug delivery • Attach filomicelles to T-cells to create filomicelle/T-cell complex. • Filomicelle/T-cell complex crosses blood-brain barrier as part of immune response
BACKGROUND • Blood-Brain Barrier (BBB): selectively permeable membrane that separates the brain from the bloodstream • Filomicelles: Di-block copolymers that can self assemble to form a vehicle for drug delivery
BACKGROUND • T-cells: immune cells with targeting receptors for filomicelle attachment • Immune response: T-cells called to brain as response to inflammation, easier to pass through BBB
METHODOLOGY BBB Model Filomicelles
OBJECTIVE ONE: CREATE A PHYSIOLOGICALLY REPRESENTATIVE BBB MODEL • Creating the BBB Model • Testing Barrier Properties • Disrupting the Barrier
CREATING THE BBB MODEL • Consists of two parts • Creating a hydrogel with appropriate stiffness • Polyacrylamide (PA) • 0.2 – 1.0 Kpa • PA gels coated with ECM protein • Forming a HBMECs monolayer • Cultured according to manufacturer’s protocol • p2-5 plated on gels Human Brain Microvascular Endothelial Cells Extracellular Matrix
TESTING BARRIER PROPERTIES • TEER Testing • Using a Endohm Chamber and Voltohmeter • Starting day 2 after plating • Adhesion proteins • Visualization of cell borders • Primary and secondary antibody staining HUVEC morphology at monolayer confluency on fibronectin-coated polyacrylamide gels. Scale bar indicate 50 µm. After monolayer formation, HUVECs were treated with Hoechst nuclear stain (blue) and cell borders are stained with anti-β-catenin antibody (green).
DISRUPTING THE BARRIER • TNF-α and IL-1α • Concentration in increasing magnitude • Representing different diseased states
OBJECTIVE TWO: CREATE A FILOMICELLE/T-CELL COMPLEX Isolate T-cells Create filomicelles Make two modifications to filomicelles Let filomicelles attach to T-cells Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
Isolating T-Cells Isolate T-cells from human blood samples Currently writing IRB proposal Protocol involves magnetic labeling Anticipate no problems Cells fed through separation column in magnetic field Magnetic labeling of non T-cells using microbeads (pink) T-cells collected in tube (green) Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
Creating the Filomicelles Use two co-polymer in chloroform, rehydration techniques Takes ≈3 days We have contact with an expert in filomicelle development Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
Filomicelle Modifications Modification 1: infusion of dye Purpose: to simulate a real drug inside the filomicelle carrier Modification 2: attachment of proteins to form Filomicelle/T-cell complex Glycoproteins gp41 and gp120 OR CD-3 antibody Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
Unmodified filomicelle Filomicelle with dye Filomicelle with dye and targeting moeities Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
Filomicelle/T-Cell Complex Culture filomicelles Incubate filomicelles with T-cells & signaling molecules Two possible interactions: T-cell will engulf filomicelle (glycoproteins) Filomicelle will bind to outside of T-cell (antibody) T-cell membrane Co-receptors on T-cell Isolate T-cells Create filomicelles Filomicelle modifications Filomicelle/T-cell complex
OBJECTIVE 3: TEST FILOMICELLE/T-CELL COMPLEX ON DIFFERENT BBB MODELS Test transmigration abilities of the complex in different BBB models, which represent different stages of disease Control: filomicelle + dye modification only Hypothesis: The filomicelle-T-cell complex will permeate through the BBB models more compared to the control
Assessing Migration Insert in model will be removed Migrated complex and filomicelle will be in solution accumulated at bottom of well Measurements Fluorescence microscopy ImageJ Plate reader FACS
Anticipated Results - Testing Filomicelle/T-cell complex will exhibit more permeability through each degree of disruption in BBB as compared to the control The control filomicelle does not have mechanism to pass through the BBB model T-cell conjugation assists transmigration through BBB BBB permeability increases with increasing concentrations of TNF-α and IL-1α
Potential Obstacles Coagulation of filomicelles on membrane of BBB model Particles may get caught on the BBB model insert Filomicelle and T-cell attachment could dislodge while permeating through BBB Contamination
TIMELINE Spring 2011 – August 2011: Complete Objective 1 • Become familiar with techniques and protocols for both BBB models and filomicelles production • Create models with TNF-α and IL-1α August 2011 – December 2011: Complete Objective 2 • Infuse dye into filomicelle and test fluorescence • Create modified complex by adding glycoproteins or antibody to filomicelles • Isolate T-cells and create filomicelle/T-cell complex
TIMELINE (CONTINUED) December 2011-June 2012- Complete Objective 3 • Test the filomicelle/T-cell complex on models • Collect data to see how much of the complex crossed the barrier June 2012-May 2013 • Analyze data and submit for publication in a peer-reviewed journal (Fall 2012) • Write Gemstone Thesis
Budget • ≈ $25,000 for supplies and materials • ≈ $8,000 for travel expenses to conferences • Continuous grant application
Acknowledgements • Dr. Aranda-Espinoza – Mentor • Carlos Luna and Kim Stroka – Graduate Students • Dr. Muro and Dr. Shah – Experts • Gemstone staff
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