Blood is the most interrogated human specimen which informs scientific inquiry and directs clinical care. Yet, there is no complete Human Immune Cell Atlas that delineates the full spectrum of blood cell states across perturbations, thus limiting our understanding of circulating immune cell functionality in health and disease.
We collected peripheral blood mononuclear cells from patients with 6 immune-mediated diseases (20 patients/disease), including auto-immune and infectious diseases and healthy controls. We implemented a unique experimental design to profile rare immune cell populations and concurrently measure RNA and protein expression at the single-cell resolution.
We identified immune cell populations which are shared across conditions and others which are unique to specific disease states. Specifically, we identified that NK cells have variable gene expression signatures across diseases, revealing surprising similarities between some diseases. Co-expression analysis of gene programs from different cell states can show how different cells operate together in different diseases.
This compendium will be the largest single-cell blood atlas described to date, both in magnitude of cells and in diversity of perturbations. This novel resource will provide a catalogue of the full spectrum of blood cells, empowering the comparison of immune-mediated disease mechanisms with unprecedented granularity.