"I fell in love with the aesthetics of biology during a class. That's how it all started," says Théry. "I was fascinated by the electron microscopy images of the architecture of the cytoskeleton. It's a dynamic structure with a three-fold symmetry that constantly comes together and falls apart—a beautiful, living rose pattern." At the beginning of his career, he wanted to understand how the network of cables that radiates from the center of the cell (centrosome) and towards its periphery is structured and allows the cell to move.

That was back in 2000. During a casual discussion at the terrace of a café, he heard that the "pope of the centrosome" worked at Institut Curie, right across the street from where he was sitting!  He says that's how "a young, really excited guy met with a wise old man", Michel Bornens, and what motivated him to start a thesis and choose a career in research. Théry then became a specialist of cell mechanics, studying the forces underlying the movements and life of the cell, via the actin filaments and microtubules that are anchored to the centrosome, and can be seen as their muscles and nervous system, respectively. It did not take long for him to find success, with a paper published in Nature Cell Biology in 2005 in which he revealed that cells are not only affected by the chemistry of their environment, but also its geometry. By building microscopic squares and triangles, he showed that the cell can "feel" the shape beneath, adhere to it, and change shape. "We formulated the equations that determine the cell-division orientation axes. That was a real scoop!" he says.

Théry joined CEA in 2006 and participated in the creation of the start-up Cytoo, which leverages its expertise in micro-technologies to provide the scientific community with microstructures for biologists to study the influence of environment geometry on genome transcription and cell division: how they assemble, merge, and migrate. The start-up has been a worldwide success. He then teamed up with biochemist Laurent Blanchoin to reconstruct the basic building principles of intracellular architecture from simple mixtures of purified proteins.

This researcher has now shifted his interest to stem cells. Changes in the spatial conformation of stem cell niches affect the proliferation rate and the nature of the cells produced. "Even though hormonal stimulation remains the main factor, niche geometry does influence cell population," Théry said. Hence the idea to create a branch of his laboratory at the Saint Louis Hospital in Paris, recognized for its expertise in cell therapy for blood diseases. "If we were able to better control the amount and type of blood cells from a culture medium, this would have a direct impact on the protocol to treat these diseases," he says.