A San Francisco biotech turning immune-cell target discovery from a months-long slog into a same-day job.
In a lab a stone's throw from UCSF Mission Bay, a machine is doing something that used to take a research team an entire season. It is reading the private conversation between immune cells and a tumor - millions of exchanges at once, one single cell at a time - and it will be done before the coffee gets cold.
This is the daily reality at Shennon Biotechnologies. The company is small, roughly sixteen people, and its ambition is not. The problem it went after is the one that has quietly throttled cancer immunotherapy for years: not a shortage of clever drug ideas, but the agonizing slowness of finding which specific immune cell can actually recognize a tumor. The industry has a name for that search. It calls it finding a needle in a haystack. Shennon calls it a solvable engineering problem.
Identifying which specific T or B cells can recognize cancer antigens is like finding a needle in a haystack.
Those numbers describe a bet. The bet is that in immunotherapy, speed isn't a convenience - it's a therapy in its own right. Every week shaved off discovery is a week returned to a patient waiting on a treatment that works.
Modern immunotherapy has a dirty secret: the science moves fast, but the discovery moves slow. Before you can engineer a cell therapy, a T cell engager, or a bispecific antibody, you first have to know which immune cells recognize the enemy - and traditional methods pull those rare cells out of a crowd of millions over weeks or months. That waiting period is a tax paid in time, money, and patient lives.
Shennon's answer is a functional screen that isolates the rare, activated cells that actually do the job - and it runs on the clock of a single day.
The name is a pun - "T cell" plus "accelerator" - and the engineering underneath is exactly as direct. TCELERATOR pairs a microfluidic biochip with AI models to functionally profile millions of single cell-cell interactions at the same time. Instead of guessing which cells matter from surface markers alone, it watches what cells actually do, isolates the functionally activated rare ones, and hands back their cognate antigens.
A microfluidic device that stages millions of single-cell interactions in parallel, so rare responders don't get lost in the crowd.
Profiles cells by what they do, not just what they look like - catching the one-in-a-million cell that recognizes a tumor antigen.
Models TCR-pMHC interactions and predicts neoantigens, turning raw functional signal into validated, developable targets.
A discovered target is a beginning, not an end. Shennon's platform feeds the whole downstream pipeline of modern immunotherapy - the tools that turn a recognized antigen into a treatment.
TCR and antibody targets for solid tumors and autoimmune disease, complete with neoepitope prediction and interaction modeling.
Validated targets flow into next-generation cell therapies, T cell engagers, and bispecific antibodies aimed at the indications that resist everything else.
The through-line is solid tumors - the cancers that have stubbornly shrugged off the immunotherapy revolution that transformed blood cancers. Beyond oncology, the company plans to point the same functional lens at autoimmune disease, where knowing which immune cells misfire is just as valuable.
Li Sun's resume reads like a deliberate approach to a single problem. Materials science at MIT under Yet-Ming Chiang. A PhD in Applied Physics from Harvard, in David Weitz's celebrated microfluidics lab, focused on single-cell analysis. Then a detour into venture capital at Foundation Capital and Bessemer - where she learned to spot a bet worth making before making her own. Fittingly, one of her former firms went on to back Shennon.
Colleagues describe her method as first-principles to a fault: find the simplest, most direct solution to a problem. In her case, the problem was "why does finding a T cell take months?" - and the solution was a chip.
In March 2023, Shennon closed an oversubscribed $13 million seed round led by deep-tech investor DCVC, with Foundation Capital, AV8, and angel investors joining. The plan for the capital is refreshingly unglamorous: expand the platform's capabilities and scale discovery to build a pipeline of validated targets for solid tumors.
Work with us to cure the uncurable.
Shennon Biotechnologies founded in San Francisco by Li Sun, PhD.
Closes an oversubscribed $13M seed round led by DCVC to scale the TCELERATOR platform.
Expands platform capabilities, builds a target pipeline for solid tumors, and establishes clinical collaborations for patient-sample studies.
Presence at SITC 2025 (Society for Immunotherapy of Cancer), signaling ongoing immuno-oncology research output.
Back in that lab near Mission Bay, the machine finishes its run. The conversation between immune cell and tumor has been transcribed - millions of exchanges, sorted, scored, and handed back not as a mystery to be solved over months, but as an answer available the same afternoon.
That is the whole idea. Shennon Biotechnologies didn't set out to reinvent immunotherapy's chemistry; it set out to abolish its waiting room. If the bet pays off, the needle-in-a-haystack cliche loses its grip - not because the haystack got smaller, but because someone finally made it transparent, and made the needle glow. For patients whose tumors have outrun every other option, a faster answer is not a small thing. It might be the whole thing.