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Cellulose nanocrystals (CNCs) have great potential in many areas of research, applications, and future commercialization prospects. Recently, CNCs have emerged as attractive candidates for biomedical applications such as drug and gene delivery systems. As such, cytotoxicity studies have been the major focus in the past decade. However, despite the rod-like nature of CNCs, the potential immune response of surface-modified CNCs is not well investigated. The current study examined the potential immune and antioxidant response induced by CNCs grafted with β -cyclodextrin (CNCs- β -CD) in a human monocyte cell line (THP-1) and a mouse macrophage-like cell line (J774A.1). We analyzed the secretion of the proinflammatory cytokine, interleukin 1 β (IL-1 β ), by ELISA and mitochondria-derived reactive oxygen species (ROS) using fluorescence cell imaging and examined the intracellular levels of proteins involved in the immune and antioxidant response by immunoblotting. Our results indicated a dramatic increase neither in the IL-1 β secretion nor in the mitochondria-derived ROS resulting in no changes in the intracellular antioxidant response in THP-1 cells treated with different concentrations of CNCs- β -CD. Overall, CNCs- β -CD is nonimmunogenic and do not induce an increased antioxidant response under the conditions tested and hence has the potential to be used as a drug delivery carrier.
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Synthesis and Cytotoxicity Studies of Wood-Based Cationic Cellulose Nanocrystals as Potential Immunomodulators
Polysaccharides have been shown to have immunomodulatory properties. Modulation of the immune system plays a crucial role in physiological processes as well as in the treatment and/or prevention of autoimmune and infectious diseases. Cellulose nanocrystals (CNCs) are derived from cellulose, the most abundant polysaccharide on the earth. CNCs are an emerging class of crystalline nanomaterials with exceptional physico-chemical properties for high-end applications and commercialization prospects. The aim of this study was to design, synthesize, and evaluate the cytotoxicity of a series of biocompatible, wood-based, cationic CNCs as potential immunomodulators. The anionic CNCs were rendered cationic by grafting with cationic polymers having pendant +NMe3 and +NH3 moieties. The success of the synthesis of the cationic CNCs was evidenced by Fourier transform infrared spectroscopy, dynamic light scattering, zeta potential, and elemental analysis. No modification in the nanocrystals rod-like shape was observed in transmission electron microscopy and atomic force microscopy analyses. Cytotoxicity studies using three different cell-based assays (MTT, Neutral Red, and LIVE/DEAD®) and three relevant mouse and human immune cells indicated very low cytotoxicity of the cationic CNCs in all tested experimental conditions. Overall, our results showed that cationic CNCs are suitable to be further investigated as immunomodulators and potential vaccine nanoadjuvants.
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- Award ID(s):
- 1703890
- PAR ID:
- 10291768
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 10
- Issue:
- 8
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 1603
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/nano10081603
