Visitor of the Week: Prashant Hariharan

Meet Prashant Hariharan of Wayne State University! The PhD Candidate is in his third year of a Biomedical Engineering program and a member of Dr. Carolyn Harris’ research group that uses tissue engineering to study and treat Hydrocephalus. Prashant joins us this week at the 2021 Brain Barriers virtual meeting where he presented a poster titled “Choroid Plexus-on-a-Chip―Characterizing a microfluidic model of cerebrospinal fluid secretion to study inflammation and hypersecretion associated with hydrocephalus”. He has presented a poster before but had this to say of his experience presenting during the CSHL Brain Barriers meeting:

This conference was certainly one of the most positive poster presentations experiences of my PhD. I had more people stop by to ask me interesting questions and give me suggestions than ever before at previous conferences. This was partially because almost every project could be associated with my own in some way. This thematic closeness of the CSH-BBB community was a unique and valuable experience!

Tell us about your research.
My thesis research involves the development of an “organ-on-a-chip” model of the choroid plexus, the part of the brain responsible for secretion of the cerebrospinal fluid. This model can be described as “a miniature, functioning diorama” of the choroid plexus tissue built using cells to study how injury affects fluid secretion in the brain.

How did you decide to focus on this area/project?
When I started my PhD program, I was studying the failure of ventricular catheters used to treat patients with hydrocephalus. This involved building a biobank of failed catheters collected from patients, some of who were only a few months old. This experience compelled me to research non-surgical treatment strategies, specifically drugs that could alter fluid secretion at the choroid plexus. Subsequently, I proposed building the organ-on-a-chip model to my mentor Dr. Harris and she graciously gave me room to explore the idea.

What and/or who is the inspiration behind your scientific journey?
As cliché as it may sound, my parents and my maternal grandfather are the biggest inspirations in my scientific journey. My mother was an organic chemist who sacrificed her career to support our family; she never passes up an opportunity to teach me the botanical name of a plant or to refresh my memory with bird names and cloud types. My father and my grandfather share a passion for preserving the environment and a voracious appetite for scientific literature. Together, they gave me a sense of wonder about biology and science in general.

What impact do you hope to make through your work?
During my PhD, I hope to validate my organ-on-a-chip model of the choroid plexus, and test my hypothesis pertaining to how inflammation affects barrier integrity and fluid secretion. I also hope to answer pivotal questions about the obstruction of ventricular catheters that may help reduce the failure rate. These are very small steps towards improving the quality of life for hydrocephalus patients.

After my PhD, I aspire to add complexity and expand my organ-on-a-chip model to enable researchers studying hydrocephalus, Alzheimer’s, cancer cell transcytosis, circadian rhythms, or drug delivery to the brain, to test their hypothesis quickly and cost-effectively.

Where do you see yourself in five years?
Ideally, in 5 years, I see myself in the middle of a post-doctoral program where I am diving deeper into understanding the choroid plexus using new and interesting techniques while also improving my organ-on-a-chip model and broadening its applications. 

What do you love most about being a researcher?
There are three aspects of being a researcher that I find immensely satisfying:

1. Working to improve on a skill (such as writing or giving a lecture) and making tangible improvements after years of work.

2. Iterative problem solving that ends with finding an “elegant”, simple solution.

3. Working on projects where I can move seamlessly from the lab bench to reading literature, with both activities informing each other.

What drew you to attend this meeting?
Being a biomedical engineer and a newcomer to the choroid plexus research community, it was not clear to me if my model would add value. I was looking for experts who could opine on my work and guide me in the right direction. When my mentor Dr. Harris first brought this meeting to my attention, I noticed that many of the leading researchers within my area of interest were attending this conference. I was eager to interact with them and take their feedback on my model.

What is your key takeaway from the Meeting; and how do you plan to apply it to your work?
There are a lot of unanswered questions with regards to the role of choroid plexus and glymphatic spaces in different pathophysiologies; an understanding of how fluid moves across different compartments in the brain is still elusive. Personally, my model could find a wider application in the study of different brain barriers and could pair very well with other techniques currently being used if I could find a way to incorporate primary cells from animals of different ages as well as cells from a pluripotent source.

What feedback or advice would you share with someone considering to participate in this meeting?
My advice to anyone who may attend a future meeting would be to go through the schedule before the day of the meeting and pick out the talks and posters that are of interest. Trying to sit through every talk will tire you out and reduce your capacity to absorb or process information by the last day.

Show up with questions about your own project that have been difficult to answer and network with others doing similar research to figure out how they tackled the same issues. This may seem like an obvious thing to do but you’d be surprised how much inertia there is in doing this.

Take advantage of the ‘PI Chats’ sessions to network with PIs who may be of interest to you but do not rely solely on these sessions to interact with PIs. Reach out to them before the meeting, introduce yourself and frame your questions clearly so they can help you.

Images provided by Prashant Hariharan.

Thank you to Prashant for being this week's featured visitor. To meet other featured researchers - and discover the wide range of science that takes part in a CSHL meeting or course - go here.

Visitor of the Week: Nunya Chotiwan

Meet Nunya Chotiwan of the Umeå University (Sweden) and Molecular Infection Medicine Sweden. The Thai national is a MIMS Excellence by Choice Programme postdoctoral fellow in Dr. Anna Överby’s lab and is at CSHL participating in Blood Brain Barrier. At her inaugural CSHL meeting, Nunya presented a poster titled “Visualizing Invasion and Spread of Neurotropic Tick-borne Flavivirus in Brain by Whole Tissue Ex Vivo Imaging” and though this was “not [her] first time for a poster presentation…it [was her] first time presenting in a neuroscience conference.” The virology-trained scientist “just started working with brains 5 months ago” learned a lot from the meeting and received great feedback and tools to use towards her work.

What are your research interests? What are you working on?
My work focuses on tick-borne flaviviruses. These viruses are in the same family as the West Nile and Zika viruses but are transmitted by tick instead of mosquitoes. These viruses can cause encephalitis (inflammation of the brain), but we do not know how they enter and spread in the brain.  I am interested in using imaging techniques to capture the entry and spread of these viruses in the mouse brain.

How did you decide to make this the focus of your research?
Flavivirus is near and dear to my heart. I have studied it for several years. When I started my postdoc, I wanted to get out of my comfort zone and study this virus from other perspectives. I am always interested in brain and felt like it is very challenging to study. Since several flaviviruses cause encephalitis and there are a lot of unanswered questions in this research area, I picked this topic for my postdoc research. 

How did your scientific journey begin?
I grew up watching a lot of disaster movies, like Deep Impact, Armageddon and Outbreak. In these movies, the real heroes who saved humanity, to me, were the scientists. When I am exposed to science, either in class or in my research, I am always amazed by the complexity of the biology. I always feel excited to design experiments to solve scientific problems. This positive energy is what drives me to continue on this road. 

Was there something specific about the Blood Brain Barrier meeting that drew you to attend?
I am new to this field, I am looking for the conference where I can learn from the experts and get a feedback from my poster. My research interest is about the viral invasion into the brain, which needs to cross some types of brain barrier in order to get to the brain. This meeting is perfect for me.

What is your key takeaway from the meeting?
I always thought blood brain barrier (BBB) is a ‘wall’ that protects the brain, but this meeting gave me an appreciation that BBB is very tightly regulated and dynamic. I am also glad to learn that what I am interested in, choroid plexus, is still understudied. There are a lot of unknown areas that I can study about.

What did you pick up or learn from the meeting that you plan to apply to your work?
My goal for this conference was to find out cell specific markers to identify cell types that are infected with virus and tools to study choroid plexus. Through talks and posters, I have acquired tools, techniques and collaboration that can help me with my project.

If someone curious in attending a future iteration of this meeting asked you for feedback or advice on it, what would you tell him/her?
The quality of science at this meeting is at a high level. Experts in the field did share new findings and even their most recent unpublished data. For those familiar to the filed, you will learn the most current findings, and for those new to the field, you will still learn several exciting information and see where the field is heading.

Blood Brain Barrier is your first meeting at CSHL—what did you think of it?
I imagined that it would be a focused but relaxed meeting with a relatively small number of participants, which enhanced the interaction and networking between the participants. I also imagined that the lab is located in an urbanized area with a lot of buildings. But now that I am here, the meeting is very engaged and there are a lot of networking opportunities. The talks and presentations are very interesting but dense, so my brain is quite overwhelmed with these interesting presentations. The campus, on the other hand, is very beautiful, close to nature and very relaxing. (I am a little jealous of the scientists who work here.)

Thank you to Nunya for being this week's featured visitor. To meet other featured scientists - and discover the wide range of science that takes part in a CSHL meeting or course - go here.

Repeat Visitor: Tatiana Schnieder

Among the ~9,000 scientists we hosted this year, a number of them participated in multiple meetings and/or courses. Kicking off the 2018 edition of our Repeat Visitor series is Tatiana Schnieder, an assistant professor of clinical neurobiology at Columbia University and an adjunct assistant professor at Hunter College. Tatiana divides her work between two research labs – the neuropathology laboratory of Dr. Andrew Dwork at Columbia University Irvin Medical Center and epigenetics laboratory of Dr. Fatemeh G. Haghighi at Mount Sinai School of Medicine. This year, Tatiana took part in the 83rd CSHL Symposium on Quantitative Biology and joined the ranks of both the CSHL Protein course (Expression, Purification, & Analysis of Proteins & Protein Complexes) and The Genome Access Course (TGAC). Previously, she presented a poster during the Glia in Health & Disease meeting in 2016 as well as attended Blood Brain Barrier that same year. We reached out to Tatiana to chat with her about her experiences in CSHL meetings and courses, and to learn more about what keeps her coming back to campus.

Tell us about your research interests.

My research is focused on the question of brain-periphery interactions in psychiatric disorders. To be more specific, I am currently investigating whether or not the reported relationship between suicide and central and peripheral inflammation is mediated by changes in blood-brain barrier (BBB) permeability.

How did you decide to make this the focus of your research?

During my doctoral training, I investigated prefrontal white matter microglia in individuals who died by suicide; and although I did not find any significant differences in microglial activation between suicides and non-suicides, suicide decedents had significantly higher densities of juxtavascular phagocytic cells in dorsal white matter than diagnostically-matched non-suicide decedents. Interestingly, however, studies of animal models of psychiatric symptoms have attributed maladaptive behavior in rodents to peripheral inflammation and to the influx of peripheral immune cells into the brain parenchyma. These findings and my own findings in postmortem human brains prompted me to investigate the involvement of peripheral immune cells in pathology associated with completed suicide. Further research revealed that non-parenchymal immune cells do not contribute to the increase in perivascular cell density that we observed in suicide; which suggests that resident microglial cells -- rather than non-parenchymal immune cells -- cross-communicate immune responses between the periphery and central nervous system in suicide. Moreover, those who died by suicide had a lower surface area density of microvessels in dorsal white matter -- the same brain region where I found increased densities of perivascular phagocytes. Cumulatively, these findings indicated that changes in the properties of the neurovascular unit could be contributing to pathological changes that lead to suicide. This piqued my interest in the role of BBB in psychiatric disorders. The goal of my current project is to determine if completed suicide is associated with transcriptional, epigenetic, or protein changes in the neurovascular unit.

Expression, Purification & Analysis of Protein & Protein Complexes Class of 2018

What led you to apply for the Protein course and how has it contributed to your work?

I applied to the Protein course to find answers to the challenges I faced during the preparation of my samples for HPLC/mass spectrometry. To assess changes in the expression level of key proteins crucial for BBB function and identify novel differentially expressed proteins, I use HPLC/mass spectrometry proteomics to interrogate protein expression profiles in isolated microvessels. To investigate BBB changes in psychiatric disorders and suicide specifically, I wanted to optimize a microvessel isolation protocol from postmortem frozen human tissue. It was important for me to develop the best method for the extraction of cytosolic, membrane, and transmembrane proteins that seal a gap between the brain endothelial cells. The two-week course gave me a lot of hands-on practice in protein isolation and, through extensive communication with the Instructors and use of the course materials, I was able to come up with the optimal protocol for my project. My main takeaway from the course is that it is imperative to learn as much as possible about your protein/s of interest before you start your experiments. Know your target well because what may work for one protein can be detrimental to another.

How about TGAC? Why did you register for it and what is your key takeaway?

My BBB project involves data that will require knowledge of bioinformatics, and I want to understand what goes into the analyses of the data I produce at the bench. I took TGAC to start learning how to analyze high-throughput data obtained using next-generation sequencing methods and mass spectrometry. As for my key takeaway: Apply what you learn in the course without delay. To acquire a new skill, one needs to practice often – if not daily – therefore it is important to “play” with your data so as to avoid forgetting what you pick up from the course.

The two courses have very different formats: the Protein course consists of hands-on training in a laboratory setting while The Genome Access Course is purely computational. What can you share about the differences or similarities between your experiences in the two courses?

The Genome Access Course Class of 2018 (Spring)

The two courses I took were indeed very different: TGAC was a short two-day course, whereas Protein course was two weeks long and so requires a completely different level of commitment. What is expected of you is also different: TGAC course is mostly lecture-based with some hands-on computer work, and the Protein course is mostly lab-based with lectures sprinkled throughout the day and evening. You cannot really choose to opt out, and by the end of the first week you already feel like you are a part of a team. In fact, working in a team and as a team will be the main mode of learning in a longer course. Irrespective of which course you decide to take, you will be taught by the top experts in the field within a friendly and supportive learning environment, where you will always have the ability to discuss and clarify concepts that may be confusing. It was an amazing experience: I was challenged to step out of my comfort zone, which is how personal and professional growth happens.

The focus of the CSHL Symposium changes annually. This year its topic was “Brains & Behavior: Order & Disorder in the Nervous System,” with an emphasis on neuroscience and related technologies. Besides the overall topic, what attracted you to participate in it?

Once you graduate, it is easy to focus on your specific area of research and, sometimes, you lose sight of the bigger picture. I strive to prevent this from happening to me. As a college professor, I need to stay abreast of the new discoveries in the field of brain research, and attending the Symposium was a perfect way to catch up with the latest findings. It provided a diverse range of topics and speakers from top-notch brain research labs. When this Symposium hones in on this topic again, I would recommend aspiring neuroscientists to attend. If you haven’t yet decided what you want to dedicate your research to or are looking to expand your network, this is a great conference.

Since you’ve now experienced both meeting and course life at CSHL, what differences or similarities did you notice about the two program types?

The courses had a much more focused agenda and required a few prerequisites so you are more likely to meet people who share similar professional or academic experiences as you. The meetings, on the other hand, were eclectic and brought together people from very diverse backgrounds. But in both instances, expect to be surrounded by like-minded people enthusiastic about science and the discoveries it brings.

What did you like most about your meeting and courses this year?

I am very lucky to live a short train ride away from CSHL. Since the first CSHL meeting I attended in 2016 on Glia in Health and Disease, I keep coming back because the quality of the meetings and courses have always been stellar, and the content and organization of the events always meet my expectations. In fact, I am looking forward to attending the Blood Brain Barrier meeting in 2019.

Both the Protein course and TGAC will return to the Laboratory in 2019; and applications are already being accepted. Apply to the Protein course by January 31, 2019 here.

Thank you to Tatiana for sharing with us her experience, and we look forward to having her back at the Laboratory again. To meet other featured scientists - and discover the wide range of science that takes part in a CSHL meeting or course - go here and here.