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Abstract Black soldier fly larvae (BSFL) have demonstrated cold tolerance that suggests the presence of cryoprotective molecules. The objective of this research was to investigate if the proteins present in the BSFL have ice recrystallization inhibition (IRI) activity and how different environmental factors affect the activity. Osborne fractionation of the defatted BSFL was performed to separate the proteins based on solubility, then preparative size exclusion chromatography was used to fractionate the albumin fraction by molecular size to isolate IRI or ice binding proteins. The major proteins in the active fractions were identified by mass spectrometry, and molecular dynamic simulations were performed with two proteins identified to investigate their behaviors in an ice-water system. The main finding is the strong IRI activity of the water-soluble BSFL albumin fraction and the column fractionated fraction 1. This fraction had a 40.4-79.9% reduction in ice crystal size at 1% concentration and under a wide pH (3-9) and salt (10-200 mM NaCl) concentration. Pure proteins recovered were sequenced and identified as cuticle proteins by mass spectrometry. One cuticle protein demonstrated strong H-bonding and structural flexibility by molecular dynamic simulations, explaining the IRI and ice binding activity. This is the first time BSFL protein is reported to possess IRI activity, and such protein extract can be feasibly obtained compared to other naturally occurring antifreezing proteins.
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This content will become publicly available on January 24, 2026
Protein corona formed on lipid nanoparticles compromises delivery efficiency of mRNA cargo
Abstract Lipid nanoparticles (LNPs) are the most clinically advanced nonviral RNA-delivery vehicles, though challenges remain in fully understanding how LNPs interact with biological systems.In vivo, proteins form an associated corona on LNPs that redefines their physicochemical properties and influences delivery outcomes. Despite its importance, the LNP protein corona is challenging to study owing to the technical difficulty of selectively recovering soft nanoparticles from biological samples. Herein, we developed a quantitative, label-free mass spectrometry-based proteomics approach to characterize the protein corona on LNPs. Critically, this protein corona isolation workflow avoids artifacts introduced by the presence of endogenous nanoparticles in human biofluids. We applied continuous density gradient ultracentrifugation for protein-LNP complex isolation, with mass spectrometry for protein identification normalized to protein composition in the biofluid alone. With this approach, we quantify proteins consistently enriched in the LNP corona including vitronectin, C-reactive protein, and alpha-2-macroglobulin. We explore the impact of these corona proteins on cell uptake and mRNA expression in HepG2 human liver cells, and find that, surprisingly, increased levels of cell uptake do not correlate with increased mRNA expression in part likely due to protein corona-induced lysosomal trafficking of LNPs. Our results underscore the need to consider the protein corona in the design of LNP-based therapeutics. Abstract Figure
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- Award ID(s):
- 2305663
- PAR ID:
- 10580427
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- bioRxiv
- Sponsoring Org:
- National Science Foundation
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