The Billion Cell×Cell Project

A global effort to map, model, and engineer causal cell–cell interactions at scale.

The Billion Cell×Cell Project is a coordinated effort to build the world’s largest atlas of cell–cell encounters. By measuring defined cellular dyads across diverse biological systems, disease settings, and perturbations, the project aims to uncover the rules by which cells influence one another — and to turn those rules into a foundation for understanding, predicting, and engineering multicellular biology.

Why Cell×Cell?

Many of the most important processes in biology and medicine are not properties of single cells alone, but of communication between cells. Development, immunity, repair, degeneration, and therapy response all depend on how one cell changes the state of another.

Today’s tools have transformed our ability to catalog cell states and map tissues. But they often fall short of identifying which neighboring cells caused a response, when that response began, and how it unfolded. The Billion Cell×Cell Project is designed to fill that missing causal layer.

Scientific Objectives

1 / Map the interaction universe

Create a reference atlas across major human cell classes and states to define the matrix of cell×cell encounters that shape development, immunity, repair, and disease.

2 / Add temporal dynamics

Measure interaction trajectories across time to distinguish early sensing, commitment, durable state change, reciprocal influence, and memory.

3 / Capture human diversity

Incorporate donor variation, age, sex, ancestry, healthy and disease cohorts, and other forms of biological heterogeneity to reflect real human biology.

4 / Systematically perturb conversations

Test drugs, cytokines, genetic edits, and engineered therapies in controlled two-cell settings to reveal mechanisms and create a scalable therapy-design testbed.

5 / Enable predictive models

Generate benchmark datasets for causal inference, virtual cells-in-context, and future tissue digital twins.

Join the Project

We are building a growing community around the measurement, modeling, and engineering of cell–cell interactions. We welcome researchers, technologists, clinicians, trainees, and partners interested in contributing data, tools, models, biological systems, and ideas.