Human Cell Atlas and cell-type authentication for regenerative medicine

Regenerative medicine: Precise cell identification will improve future therapies The characterization of cells into more precise groups will improve the chances of selecting the best types of cells to use for regenerative medicine. Traditionally, cell types are defined by physiological and morphological markers and molecular properties. However, sequencing technologies are enabling researchers to classify cells into increasingly distinct subgroups. Wataru Fujibuchi at Kyoto University, Japan, and co-workers reviewed progress in cell-type identification to help guide regenerative medicine. They examined the insights gained from the Human Cell Atlas project, an international collaboration of over 1000 institutes across 71 countries. Participants in this project are sequencing cellular RNA and categorizing hundreds of thousands of individual cells, demonstrating that many assumptions about cells are too simplistic. Such data will inform regenerative therapies, for example, by selecting the best platelet-producing stem cells for blood donation. In modern biology, the correct identification of cell types is required for the developmental study of tissues and organs and the production of functional cells for cell therapies and disease modeling. For decades, cell types have been defined on the basis of morphological and physiological markers and, more recently, immunological markers and molecular properties. Recent advances in single-cell RNA sequencing have opened new doors for the characterization of cells at the individual and spatiotemporal levels on the basis of their RNA profiles, vastly transforming our understanding of cell types. The objective of this review is to survey the current progress in the field of cell-type identification, starting with the Human Cell Atlas project, which aims to sequence every cell in the human body, to molecular marker databases for individual cell types and other sources that address cell-type identification for regenerative medicine based on cell data guidelines.