Below is the first part of a two-part series summarizing the talks presented at the 3rd Annual NanoBio Symposium hosted by the Johns Hopkins Institute for NanoBioTechnology, on May 18, 2009. Four talks from the eight speakers who presented that day are described below.
Novel Approaches to Understand Neurodegenerative and Neuropsychiatric Diseases
Ted Dawson – Leonard and Madlyn Abramson Professor of Neurodegenerative Diseases, Department of Neurology; Institute for Cell Engineering, Johns Hopkins School of Medicine
Inducible pluripotent stem cells (iPS) derived from patients with Parkinson’s disease, schizophrenia, autism spectrum disorders, Down syndrome and other neurodegenerative or neuropsychiatric conditions could become better tools to study disease processes than mouse models, which lack certain genetic markers found in humans. By transplanting human-derived iPS cells that exhibit neurological conditions into animals, scientists could create human disease-specific models that will serve as the drug screening platform for the future. The Institute for Cell Engineering works with scientists from INBT to use nanofibers, quantum dots and other methods to control and direct differentiation of iPS cells into neurological cells, such as astrocytes, oligodendrocytes and neurons. (by Mary Spiro)
Developing Contrast Agents for Imaging Drug Delivery
Michael McMahon -Assistant Professor, Radiology/MR Division; FM Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Johns Hopkins School of Medicine
Contrast agents are often used in conjunction with medical imaging to enhance images. Michael McMahon explained how he and his colleagues are developing magnetic resonance contrast agents based on the imaging technique Chemical Exchange Saturation Transfer (CEST) that exhibit distinct colors similar to fluorescent agents. They recently incorporated these contrast agents into liposomes, which are vehicles for drug delivery. They injected the liposomes into mice and detected the contrast agent at various times post-injection. Due to their distinct colors, CEST-based contrast agents could prove useful for imaging drug delivery and release in humans. (by Adam Book)
Using Nanotechnology to Guide Blood Vessel Formation
Sharon Gerecht – Assistant Professor, Department Chemical and Biomolecular Engineering; Institute for NanoBioTechnology; Whiting School of Engineering, Johns Hopkins University
Stem cells can become a wide variety of specialized cell types. One type of stem cell, the endothelial progenitor cell (EPC), grows into cells that form blood vessels. Sharon Gerecht described how she is developing surfaces that guide EPCs into forming blood vessels. They grew EPCs on either flat or nanotopographic surfaces. Cells on the flat surface grew randomly, while cells on the nanotopographic surface aligned with the nanoscale etchings. Gerecht is currently determining the best way to persuade the cells to form the proper three-dimensional organization of living blood vessel networks. (by Adam Book)
Directing Stem Cell Fate with Nanofiber Matrices
Hai-Quan Mao – Assistant Professor, Department of Materials Science and Engineering, Whitaker Biomedical Engineering Institute; Whiting School of Engineering, Johns Hopkins University
The use of stem cells to replace diseased tissues in the body is a promising avenue of research. However, this therapy depends on the stem cells surviving and growing into the correct type of cell after being placed in the body. Hai-Quan Mao talked about a technique for growing neural stem cells on nanofiber matrices, which can be manipulated to form the various environments found in the human body. By altering the nanotopography of the matrix and adding chemical cues, they can coax a neural stem cell to differentiate into a desired cell type. (by Adam Book)
Future Applications of Nanotechnology for the Treatment of Brain Tumors
Alessandro Olivi – Professor, Neurosurgery and Oncology; Chair, Department of Neurosurgery, Johns Hopkins Bayview Medical Center
Recent neurosurgical advances in imaging, preoperative planning, microsurgical techniques, and intra-operative and post-operative patient care are improving the treatment of brain tumors. Better imaging allows more precise targeting of the affected area and the determination of the optimal trajectory for procedures that are minimally invasive and more respectful of function. The use of nanoparticles for drug delivery, targeted nanoparticle immunotherapy, thermotherapy, photodynamic therapy, intracellular delivery, and the use of nanoparticles to increase MRI image delineation of brain tumors holds much promise with increased survival time. Targeted immunotherapy includes intercellular delivery and delivery via incapsulation and coating. Targeted drug delivery of chemotherapy agents over a three to four week period at the level of the tumor bed is now possible via the Gliadel Wafer. The use of nanotechnology will likely bring us to the next level in the treatment of malignant brain tumors. (by Gina Hagler)
*Gina Hagler is a is a master’s degree candidate in the Science and Medical Writing through the Krieger School of Arts and Sciences, Advanced Academic Programs.
**Adam Book is a master’s degree candidate in the Science and Medical Writing through the Krieger School of Arts and Sciences, Advanced Academic Programs.