Abstract
Cells contain membrane-bound and membraneless organelles that operate as spatially distinct biochemical niches. However, these reaction centers lose fidelity due to aging or diseases. A grand challenge for biomedicine is restoring or augmenting cellular functionalities. An excited strategy is the delivery of protein-based materials that can directly interact with cellular biological networks. In this study, we sought to develop long-lasting materials capable of cellular uptake, akin to intracellular interaction hubs. We develop a delivery method to efficiently transplant stable micron-size peptide-based compartments into living cells. By loading coacervates with nanobodies and bioPROTACs, we demonstrate successful target sequestration of natively expressed GFP to our synthetic hubs, and function as bioreactors to selectively degrade GFP inside human cells. These results represent an important step toward the development of synthetic organelles that can be fabricated in vitro and taken up by cells for applications in cell engineering and regenerative medicine.
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The data supporting the findings of this study are available within the Article and Supplementary Information. Source data are provided as Source Data files. Source data are provided with this paper.
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Acknowledgements
We thank A. Stout and the Penn CDB Microscopy Core for imaging support, M. Wadley for human primary monocytes cell culture, and W. Wentao for FACS for GFP cell line generation. We thank Emily Cento, Zhilin Chen, Max A. Eldabbas, and Emileigh Maddox of the Human Immunology Core and the Division of Transfusion Medicine and Therapeutic Pathology at the Perelman School of Medicine at the University of Pennsylvania for providing de-identified, primary human monocytes that were purified from healthy donor apheresis using StemCell RosetteSep™ kits. The HIC is supported in part by NIH P30 AI045008 and P30 CA016520. This study was partially supported by the National Institute of Biomedical Imaging and Bioengineering grant, EB028320 (M.C.G.), by National Science Foundation through the University of Pennsylvania Materials Research Science and Engineering Center (MRSEC) (DMR-2309043), and a seed award from the Center for Precision Engineering for Health (CPE4H) at the University of Pennsylvania (M.C.G., A.J.P.).
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M.C.G, W.T., and A.J.P. conceptualized the project. M.C.G., W.T., R.Q.T., and D.M.C. designed the experiments. W.T. and P.J. performed initial peptide synthesis. W.T. and R.Q.T. designed and cloned genetic constructs. W.T. purified cargo and nanobody proteins and performed experiments for assembly, co-assembly, FRAP, in vitro targeting experiments, and coacervate stability experiments. W.T. and R.Q.T performed imaging for characterization of coacervate distribution and mobility in various cell types. W.T. performed experiments for GFP targeting in cells. W.T. analyzed experimental data. M.C.G and W.T. wrote the manuscript with feedback from A.J.P. and D.M.C.
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Tu, W., Theisen, R.Q., Jin, P. et al. Delivery of peptide coacervates to form stable interaction hubs in cells. Nat Commun (2026). https://doi.org/10.1038/s41467-026-68793-7
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DOI: https://doi.org/10.1038/s41467-026-68793-7
