In vitro and ex vivo strategies for intracellular delivery

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Intracellular delivery of materials has become a critical component of genome-editing approaches, ex vivo cell-based therapies, and a diversity of fundamental research applications. Limitations of current technologies motivate development of next-generation systems that can deliver a broad variety of cargo to diverse cell types. Here we review in vitro and ex vivo intracellular delivery approaches with a focus on mechanisms, challenges and opportunities. In particular, we emphasize membrane-disruption-based delivery methods and the transformative role of nanotechnology, microfluidics and laboratory-on-chip technology in advancing the field.

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Figure 1: Intracellular delivery is a key step in investigating and engineering cells.
Figure 2: Map of the relationship between intracellular delivery approaches, basic mechanism and conventional physical and biochemical categorizations.
Figure 3: Membrane disruption and recovery in the context of intracellular delivery.
Figure 4: Selected modes of bulk, microscale and nanoscale approaches for membrane-disruption-based intracellular delivery.


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This work was supported by the US National Institute of Health (R01GM101420-01A1). M.P.S. was supported by the Swiss NSF through the advanced postdoc mobility fellowship P300P3_151179. M.P.S. acknowledges support from a Keith Murdoch Fellowship via the American Australian Association, a Life Sciences Research Foundation Fellowship sponsored by Good Ventures, and a Broadnext10 Catalytic Steps funding gift from the Broad Institute. A.S. was supported by a Ragon Institute fellowship. We thank the following people for comments and constructive criticism: E. van Leen, D. Irvine, J. Voldman, S. Manalis, J. Weaver, J. Lieberman, R. Karnik, R. Lee, D. Mueller, S. Bhakdi, Y. Toyoda, Z. Maliga, H.-J. Lee, N. Yang, E. Lim, R. Sayde and K. Blagovic.

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R.L. and K.F.J. shaped ideas and provided guidance. M.P.S. constructed the figures. M.P.S. and A.S. wrote the manuscript (with assistance from X.D. and G.S.).

Correspondence to Robert Langer or Klavs F. Jensen.

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A.S., K.F.J. and R.L. have a financial interest in SQZ Biotech, a startup company focused on engineering immune cell function for cell based therapies (

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Nature thanks L. Lee, M. Prausnitz and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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Stewart, M., Sharei, A., Ding, X. et al. In vitro and ex vivo strategies for intracellular delivery. Nature 538, 183–192 (2016) doi:10.1038/nature19764

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