Photothermal Delivery of Large Cargo into Mammalian Cells
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: It is currently impossible to transfer certain large biomolecules and structures, such as chromosomes, organelles, pathogens, or even the nucleus into soft, fragile cells, such as normal body cells or embryonic stem cells (ESCs). This roadblock in enabling technology precludes the generation of accurate models of certain diseases for studies of drug efficacy or mechanisms of action. This impediment also blocks the engineering of replacement cells with modified components, such as repaired mitochondria for energy generation, and the development of advanced regenerative medicine approaches of the future. In this proposal, we provide a radically new approach to generate designer cells that model human disease and advance futuristic therapies. We focus on this new technology, termed photothermal microinjection, and on its automation as a rapid, large-scale delivery vehicle for 100,000 or more cells, as well as on its miniaturization, to provide access for California’s academic and commercial biotechnology labs. We further focus on chromosome transfer into ESCs as an initial, and high impact, proof-in-principle operation that will generate highly unique and valuable cell resources currently unobtainable by other methods. For over 3 years, Drs. Chiou and Teitell have collaborated to invent this new approach that consists of a metallic thin film firmly attached to the tip of an injection micropipette that is used to deliver large cargos, such as chromosomes or live pathogens, into living cells. This specialized pipette is placed lightly touching a cell membrane by a robotic controller on a microscope stage. A pulse of non-damaging laser light rapidly heats the thin film so that it can generate a precisely sized membrane opening that re-seals after material transfer from the delivery pipette. This technique is not a simple improvement of standard microinjection technology used in infertility clinics, for example. Rather, it is a fusion between the most desirable aspects of pressurized cargo delivery and a new, light energy-driven method to open a delivery window in a cell membrane that is much larger, and safer, than any other method. Pilot studies have shown transfer efficiencies of ~50% with cell viabilities of &gt;90% for introducing live bacteria into human cells, an operation that is currently impossible with any other known technology or approach. We have assembled a very strong team with expertise in optics and electronics, cancer and stem cell biology to lead this effort. OUR PROJECT GOAL is to 1) optimize photothermal microinjection and generate valuable chromosome-transferred ESCs for future studies beyond this proposal, 2) develop a high-throughput platform to enable large cargo delivery into 100,000 cells or more simultaneously for delivering multiple cargo combinations and 3) miniaturize our invention so that it can be shared with California’s academic and bio-industrial centers to benefit its people and economy.