Faces of the Foundation: Asmamaw Wassie

April 2, 2018
Bennett McIntosh
Livermore, Calif

Asmamaw “Oz” Wassie is taking engineering to a new frontier – the inner workings of our brain.

Before he was a Hertz Fellow, as a first-year graduate student in MIT’s bioengineering program, Oz had already helped build an electronic nose to smell trace elements in the air through DARPA’s RealNose program. He cast about for other interesting biological systems to tinker with, motivated, he said, by a simple metric: “I want to do cool stuff.”

He found that “cool stuff” in the lab of Hertz Fellow Ed Boyden, where an interdisciplinary team of scientists and engineers were building new tools to study the brain. It seemed like a field ripe for an engineer like Oz. “Neuroscience is an area that could greatly benefit from engineering, for research and therapeutics.”

At the same time, Oz applied for the Hertz Fellowship, after hearing about it from Fellow James Pelletier, who had just joined the same lab that Oz worked in as an undergrad. “I saw it was a unique set of individuals, driven and ambitious, who are not OK with what is currently possible,” says Oz. “I wanted to be a part of this.”

Upon joining the Boyden lab and the Hertz Community, Oz says he found two groups of researchers who are “fearless” in their choice of project – which exactly meshed with his style. His first project in the Boyden lab was an ambitious attempt to measure the activity of neurons in living brains with extremely small diamonds (“nanodiamonds”). As often happens with risky projects, the idea didn’t pan out from a technical standpoint, but Oz says he learned the failure, both as a scientist and as a student.

His next projects both built off of Expansion Microscopy, a technique developed by a team in Boyden’s lab, including Hertz Fellow Paul Tillberg, now a Fellow at the Janelia Research Campus. The technique uses an expanding polymer to physically swell biological samples, letting ordinary microscopes examine the samples in much richer detail.

Ordinarily, Expansion Microscopy expands the tissue’s volume about 100-fold – much bigger, but still too small to see some of the smallest molecular features of a cell. By the simple expedient of re-applying the technique to expand the sample once again, a team of researchers including Oz found that they could grow samples large enough to visualize the proteins in the synapses between neurons.

At the same time, Oz and fellow PhD student Fei Chen were developing a technique called ExFISH, which used expansion microscopy to show the position of important RNA sequences within tissue samples. RNA is the molecule that carries the instructions from DNA to the cell’s protein-making machinery, so the RNA in a given cell gives an excellent snapshot of what it is doing in this very moment. Finding RNA sequences of a tumor or tissue sample, on a cell-by-cell basis, thus gives a fine-grained snapshot of how an entire complex of cells is behaving at a given time.

“It’s possible to use ExFISH to see what’s different between different cell types, and what makes one cell type within a tumor more susceptible to treatment than another cell type,” says Oz.

And it’s not just tumors. Neurodegenerative diseases like Alzheimer’s, or any other disease that involves interactions between different cells, could reveal their secrets under ExFISH.

For the rest of his Hertz Fellowship and beyond, Oz plans to continue developing new technologies to tackle problems in neuroscience and the life sciences in general. “Whenever I get the opportunity I try to take on risky and impactful ideas,” he says.