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Vaccine Adjuvants in Immunotoxicology
Published in Mesut Karahan, Synthetic Peptide Vaccine Models, 2021
Self-assembling concept-generated nanosize vaccine candidates utilize the well-documented aggregation properties of certain peptides. The advantages of the self-assembling peptide materials include molecular specificity, nanoscaled positioning of the ligands, multivalency, multifunctionality, and biocompatibility (Skwarczynski and Toth 2011). Yano et al. have reported that use of nanoparticles increased the binding of the peptide epitopes to the specific receptors in the immune system when peptide epitopes are assembled into arginine-glycine-aspartate nanoparticles (Yano et al. 2005). However, peptide-based conjugates have lower immunogenic properties compared to lipid and polymer-based nanostructures; therefore, peptide-based conjugates require a use at higher doses (Zhao et al. 2017).
Regeneration: Nanomaterials for Tissue Regeneration
Published in Harry F. Tibbals, Medical Nanotechnology and Nanomedicine, 2017
A recent study led by Rutledge Ellis-Behnke of Massachusetts Institute of Technology is an example of the versatility of self-assembly for neural scaffolds. In this research, a peptide-based nanofiber scaffold was used to enable the regeneration of the severed optic tract in the hamster brain. This represented a significant milestone for in vivo brain regeneration. Ellis-Behnke and his colleagues used a self-assembling peptide scaffold material that had been shown to be permissive for cell attachment in previous in vitro experiments. Synthetic peptide polymers have the following advantages: they form a network of nanofibers similar to the natural extracellular network in scale and composition; they biodegrade into natural L-amino acids potentially usable by the surrounding tissue; they are free of chemical and biological contaminants that typically are present in animal-derived biomaterials such as collagens; and they appear relatively immunologically inert. The peptide sequences are synthesized to present targets for cell attachment, such as arginine-alanine-aspartate-alanine (RADA), which is known to promote neuron growth. Visual ability was regained in 75% of the treated animals [103]. The scaffolds were also used to reknit spinal cord injuries in rats [104].
Intelligent Nanomaterials for Medicine: Carrier Platforms and Targeting Strategies—State of the Art
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
Georgette B. Salieb-Beugelaar, Marc Wolf, Roman Lehner, Kegang Liu, Stephan Marsch, Patrick Hunziker
Peptides can have lipophilic or hydrophilic properties based on their amino acid composition and can therefore be used to construct amphiphilic molecules that form nanostructures by self-assembly [132–134]. Design considerations of these biopolymers for drug carriers are similar to other biocompatible polymers, but should take into account that peptides may act as strong immunogens and that the body already contains several lines of defense against foreign proteins and peptidic structures like virus capsids. In addition, a variety of peptidases exist in the body; if a system is preclinically developed for later clinical use in man, species differences in peptidase expression needs to be carefully considered. Virus self-assembly can act as an inspiration to build hollow or solid peptidic nanostructures [135, 136]. Bawa et al. showed enhanced cellular delivery and activity of the anticancer drug ellipticine to human lung carcinoma A549 cells using self-assembling peptide-based nanoparticles [137]. Naskar et al. presented the formation of multivesicular structures from self-assembling peptides, depicting sensitivity upon exposure to calcium ions leading to vesicular disruption. This intelligent sensing/switching functionality, allows cargo release suited for medically relevant payloads [138]. However, a natural extension of peptide-based systems is the exploitation of biologic peptide functions like their use as receptor ligands or enzymatic activity, naturally leading to nanomaterials with complex or switchable functionalities. Clinically, peptidic systems have entered clinical trials dominantly as nanoplatforms for vaccines offering multivalency as a potent immune system stimulant.
Self-assembling peptides-based nano-cargos for targeted chemotherapy and immunotherapy of tumors: recent developments, challenges, and future perspectives
Published in Drug Delivery, 2022
Xue-Jun Wang, Jian Cheng, Le-Yi Zhang, Jun-Gang Zhang
Multivalency is a critical property of self-assembling nanostructures, as it enables the formation of multivalent interactions, which improve the binding affinity of weakly specific interactions (Lim et al., 2009a). Self-assembling peptides have the important property of multivalency because peptides produce self-assembling nanoparticles by a bottom-up self-assembling process. Immune system activation can be caused by multivalent antigens recognized by B cells, which are important in bioactive functionalization (Puffer et al., 2007). Furthermore, in biological systems, multivalency plays a significant role in enhancing avidity and specificity, whereas monovalency does neither as well. The associativity of receptors can be improved by reorganizing some of the receptors on the cell surface into multivalency. Thus, multivalency SAPs can be used to activate immunogenicity and promote immunotherapy for tumors (Rudra et al., 2012). Vaccines and vaccine adjuvants against tumor cells are currently being developed using SAPs with multivalency (Collier, 2008). SAPs have a unique advantage in immunotherapy and other fields because of their multivalency (Liu & Kiick, 2008).
Novel temporin L antimicrobial peptides: promoting self-assembling by lipidic tags to tackle superbugs
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Rosa Bellavita, Annarita Falanga, Elisabetta Buommino, Francesco Merlino, Bruno Casciaro, Floriana Cappiello, Maria Luisa Mangoni, Ettore Novellino, Maria Rosaria Catania, Rossella Paolillo, Paolo Grieco, Stefania Galdiero
Much research is focussed on membrane interactions of monomeric AMPs and how to control lipid affinity to obtain selective destruction of bacterial membranes48,49. However, growing shreds of evidence have shown that AMPs self-assembly offers great opportunities to modify the ratio between hydrophobicity and hydrophilicity and thus antimicrobial activity and selectivity50. Nevertheless, aggregation of amphiphilic peptides decreases their effective hydrophobicity masking the apolar moieties from the aqueous phase and membrane binding is reduced. Moreover, in model membranes mechanisms that are present in cellular studies and that could affect selectivity through aggregation, are likely absent; self-assembled AMPs might be ineffective in crossing the LPS layer or the cell wall, and thus in reaching the plasma membrane of bacteria while being still able to interact with the unprotected membrane of host cells. These drawbacks are responsible for the fact that the development of self-assembling peptides with antibacterial activity has not been widely exploited.
The interaction between self – assembling peptides and emodin and the controlled release of emodin from in-situ hydrogel
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Weipeng Wei, Cui Meng, Yuhe Wang, Yongsheng Huang, Wenbin Du, Hongfang Li, Yanfei Liu, Hong Song, Fushan Tang
In recent years, self-assembling peptides have been widely researched as nanomaterials in cell culture [23,24], tissue engineering, organ regeneration repairing [25–28], hemostasis [29,30], drug delivery [31–35] and other biomedical fields. Self-assembling peptides include ion-complementary self-assembling peptides, amphiphilic peptides, cyclic peptides, surface-active peptides, aromatic peptides, and many other types [36]. Among them, ion-complementary self-assembling peptides have attracted the most research interests of many researchers. The ion-complementary self-assembling peptides contain alternately arranging positively charged amino acids and negatively charged amino acids with hydrophobic amino acids in their structures, and thus can self-assemble under the electrostatic force, hydrophobic interaction and hydrogen bond [37]. Studies have shown that the ion-complementary self-assembling peptide RADA16-I (shown in Figure 1(B)) is not only a potential carrier for protein drugs [20], but also can pack strong anticancer activity of the drug paclitaxel [38] and 5-fluorouracil [39]. The potential of ion-complementary self-assembling peptides as carrier of hydrophobic drugs need to be exploited and verified through further subsequent researches.