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Rethinking nomenclature for interspecies cell fusions

Nature Reviews Genetics volume 23, pages 315–320 (2022)Cite this article

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Abstract

Cell fusions have a long history of supporting 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 involving human and chimpanzee pluripotent stem cells, rather than somatic cells, highlight the need for responsible communication and a revised nomenclature. Applying the terms ‘hybrid’ and ‘parental’ to the fused and source cell lines, respectively, evokes reproductive relationships that do not exist between humans and other species. These misnomers become more salient in the context of fused pluripotent stem cells derived from different but closely related species. Here, we propose a precise, versatile and generalizable framework to describe these fused cell lines. We recommend the term ‘composite cell line’, to distinguish cell lines that are experimentally created through fusions from both reproductive hybrids and natural cell fusion events without obscuring the model in overly technical terms. For scientific audiences, we further recommend technical nomenclature that describes the contributing species, ploidy and cell type.

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Fig. 1: Distinct nomenclature for reproductive hybrids and composite cell lines.
Fig. 2: Example of nomenclature applied to a three-species composite cell line.

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Acknowledgements

N.K.S. is supported by the Weill Neurohub Fellowship. A.A.P. acknowledges funding from the National Institutes of Health (NIH) (DP2MH122400-01), the Schmidt Futures Foundation and the Shurl and Kay Curci Foundation and is a New York Stem Cell Foundation Robertson Investigator. The authors acknowledge C. Lowe, C. Dorsett and members of the Pollen laboratory for critical feedback and insights.

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Authors and Affiliations

  1. The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, USA

    Bryan J. Pavlovic, Nathan K. Schaefer & Alex A. Pollen

  2. Department of Neurology, University of California San Francisco, San Francisco, CA, USA

    Bryan J. Pavlovic, Nathan K. Schaefer & Alex A. Pollen

  3. Center for Health Law Policy & Bioethics, University of San Diego, School of Law, San Diego, CA, USA

    Dov Fox

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Correspondence to Alex A. Pollen.

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Pavlovic, B.J., Fox, D., Schaefer, N.K. et al. Rethinking nomenclature for interspecies cell fusions. Nat Rev Genet 23, 315–320 (2022). https://doi.org/10.1038/s41576-021-00447-4

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