bioRxiv preprint doi: https://doi.org/10.1101/2020.02.11.944504; this version posted February 12, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Kupffer Cell Release of Platelet Activating Factor Drives Dose Limiting Toxicities of Nucleic Acid Nanocarriers. Meredith A. Jackson1, Shrusti S. Patel1, Fang Yu1, Matthew A. Cottam2, Evan B. Glass1, Bryan R. Dollinger1, Ella N. Hoogenboezem1, Prarthana Patil1, Danielle D. Liu1, Isom B. Kelly1, Sean K. Bedingfield1, Allyson R. King1, Rachel E. Miles1, Alyssa M. Hasty2,3, Todd D. Giorgio1, Craig L. Duvall1*. 1Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA 2Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA 3Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, 37212, USA *Email:
[email protected] bioRxiv preprint doi: https://doi.org/10.1101/2020.02.11.944504; this version posted February 12, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Abstract In vivo nanocarrier-associated toxicity is a significant and poorly understood hurdle to clinical translation of siRNA nanomedicines. In this work, we demonstrate that platelet activating factor (PAF), an inflammatory lipid mediator, plays a key role in nanocarrier- associated toxicities, and that prophylactic inhibition of the PAF receptor (PAFR) completely prevents these toxicities.