Topographical Effects in Neuronal Calcium Signaling
- Soft-gel Microchannels to Study Curvature Effects in Neuronal Calcium Signaling.
- Fine-tuning Agarose Concentrations towards Soft-gel based Neuro-microfluidics
Much of my undergraduate work has revolved around designing and fabricating microenvironment to observe neuronal growth and communication. Particularly looking at how perturbations in various physical topographies effect calcium communication. So why start there? To begin, we need to first take a look at how the human brain develops and changes over time. It is no means a flat plane, rather the neocortex is filled with these "hills and valleys". Biological evolution has allowed our brains to attain a very large volume relative to surface area. Hilgetag and Barbas explain this very well. If we can model the finer topographical structures in the human cortex on a petri dish, then it stands that we can learn some of the factors that play a role in the morphology of cellular communication and subnetworks.
So why am I, an electrical engineer, researching this? Well, currently there is a multitude of techniques that capture neuronal development and communication in vitro. However, systemically elucidating neuronal communication using a curvature confinement within a petri dish has not been done. How does different bending affect the way that cells signal each other? What about cellular growth? When I first joined Kunze Neuroengineering lab on the summer of my junior year, microfabricating devices provided an avenue of interest. My advisor, Dr. Anja Kunze, thought it would be a great start to point me towards fabricating biocompatible microstructures to observe the way the neurons grow and communicate. At twenty years old I set off to piece together how to create a device that can do just that.
In hindsight I realize that much of my journey started off as any other researcher: absolute perplexity. Given the fact that I was several decades behind current neuroengineering methods, I had a lot of catching up to do. Eventually I settled on rerunning a couple of old experiments on agarose hydrogel. I later figured out that agarose was very straightforward to implement in cell culture systems. Given its thermo-responsive nature, it was also relatively easy to fabricate and best of all biocompatible. Much of my junior year was studying how neurons interacted with agarose. Eventually, I moved on to designing some sort of structure that can use agarose as a barrier to facilitate confine growth between neuronal networks. In collaboration with another undergraduate (now graduate student), we designed a high-throughput cell assay that allowed neurons to growth within their own confined curvatures using agarose hydrogels as a means of fabrication. This was when the project took off and now, six months later, the results that we obtained describes neuronal communication much better than we had any right to expect.
Elucidating Fundamental Biological Functions at Single-Cell Resolution
I am very interested in answering three questions in the neuroengineering field. First, can we rationally build a close-loop system that allows us to observe as many stages of the cellular network as we can? Secondly, how can we holistically quantify perturbations from single cell or sub-network communication? Thirdly, how can we better communicate our respective scientific discoveries to scientists of all fields? Since much of my work has been revolved around in vitro studies, I am curious on how to best translate discoveries between in vitro and in vivo. Much of these questions revolve around breaking down what we already know about the methods of each respective experimentation. There are several complications that arise from in vivo experimentation. There is a limitation on how invasive we want the device to be to study brain models, additionally there is the challenge of explaining the biological impacts of invasive methods. Temporally advantageous long term studies also restrict the repetition on how many times we can conduct the same experiment or if we want to test against a control. Remember systematic research requires changing only one variable at a time. As a result we see that in vitro studies prove promising in understanding sub-cellular environments of cell growth and communication. High throughput analysis can be done with rapid repeatability. The problem is translating any of these findings to in vivo models can lead to unreliable conclusions.
Therefore can we design a device that accurately mimics the in vivo environment of the human brain while simultaneously conducting temporally intensive high throughout experiments with high repeatability?
Disclosure: Since I have only been conducting neuroengineering research for two years much of my interest could change as I become more exposed to different methods and fields. But for now this is what I can envision my research going.
Novel Techniques in Controlling Sub-cellular Behaviors
- Quantifying Magnetic Nanoparticle Movement Under Micromagnetic Field Patterns.
- Neural network growth under heterogenous magnetic gradient patterns.
Magnetic nanoparticles are a versatile tool to modulate calcium signaling, alter intracellular vesicle dynamics, or interfere with gene expression in cerebral neurons through imposing magnetic field gradients on the nanoparticles
Currently, we are working on characterizing nanoparticle movement under define magnetic field patterns. Since magnetic interaction with neurons depend heavily on spatial information, quantifying how nanoparticles move through different magnetic field gradients is of much interest. Here we presented a method on how to track nanoparticle movement using particle image velocimetry (PIV). Additionally, we have found that inducing nanoparticle movement can influence cellular growth and orientation.
Using this application, I am part of a biotechnological startup in hopes to commercialize a product that our team has been working on. It is definitely an exciting venture for me – I have never been a part of a business driven project, and I hope we can push this project forward based on the previous research that we have done.