Talking to cells: biomolecular ultrasound to image and control cells deep inside the body

Terms: No registration required, subject to availability
Audience: Intended for a scientific audience
Speaker: Mikhail G. Shapiro, Professor of Chemical and Medical Engineering at Caltech, Fulbright France - Tocqueville Chair Laureate 2024/25

Studying biological functions in intact organisms and developing targeted cellular therapies requires methods to image and control specific cell functions deep within the body. Fluorescent proteins and optogenetics fulfill this role in small, translucent specimens but are limited by the poor penetration of light into deeper tissues. In contrast, most non-invasive techniques, such as ultrasound and magnetic resonance imaging, rely on energy forms that penetrate tissue but are not effectively coupled to cellular function. The work of Mikhail G. Shapiro’s team seeks to bridge this gap by engineering biomolecules with the physical properties necessary to interact with sound waves and magnetic fields.

In this talk, Mikhail G. Shapiro will discuss his recent advances in biomolecular reporters and actuators for ultrasound. These reporters are based on gas vesicles—a unique class of air-filled protein nanostructures derived from buoyant photosynthetic microbes. These proteins scatter sound waves, enabling their detection via ultrasound. Shapiro will describe his team’s progress in understanding the biophysical and acoustic properties of these biomolecules, introducing them genetically into various cell types for in vivo imaging, and converting them into dynamic sensors of intracellular molecular signals.

Beyond their imaging applications, gas vesicles can also be used to control cellular location and function. They act as receivers of acoustic radiation force or can seed localized bubble cavitation. Additional control mechanisms are provided by thermal bioswitches—biomolecules that enable switch-like regulation of gene expression in response to slight temperature changes. Mikhail G. Shapiro will explain how these functionalities support the development of remote-controlled cell therapies and engineered biomaterials.