Rethinking Nomenclature for Interspecies Cell Fusions

Abstract

Cell fusions have long enhanced biomedical research. These experimental models, historically referred to as ‘somatic cell hybrids,’ involve combining the plasma membranes of two cells and merging their nuclei within a single cytoplasm. Cell fusion studies that involve human and chimpanzee pluripotent stem cells highlight the need for careful and principled communication. Names matter. How scientists describe cell lines can shape public perception and inform policy. Referring to source cell lines as ‘parental,’ or calling fused cells ‘hybrids’ evokes a reproductive potential that doesn't exist between humans and other species. We propose a precise, versatile, and generalizable nomenclature that describes the contributing species, ploidy, and cell type. For lay audiences, we recommend the term ‘composite cell line’ to distinguish experimentally fused cell lines from natural cell fusion events and actual reproductive hybrids.

Keywords: cross-species, cybrid, hybrid, chimera, cell fusion, pluripotent stem cells, composite cell line, embryogenesis, 14-day rule, science communication, biomedical research ethics