Harnessing the Potential of Self-Assembled Peptide Hydrogels for Neural Regeneration and Tissue Engineering.

Spinal cord injury, traumatic brain injury, and neurosurgery procedures usually lead to neural tissue damage. Self-assembled peptide (SAP) hydrogels, a type of innovative hierarchical nanofiber-forming peptide sequences serving as hydrogelators, have emerged as a promising solution for repairing tissue defects and promoting neural tissue regeneration. SAPs possess numerous features, such as adaptable morphologies, biocompatibility, injectability, tunable mechanical stability, and mimicking of the native extracellular matrix. This review explores the capacity of neural cell regeneration and examines the critical aspects of SAPs in neuroregeneration, including their biochemical composition, topology, mechanical behavior, conductivity, and degradability. Additionally, it delves into the latest strategies involving SAPs for central or peripheral neural tissue engineering. Finally, the prospects of SAP hydrogel design and development in the realm of neuroregeneration are discussed.

Nanotechnology-based cell-mediated delivery systems for cancer therapy and diagnosis.

The global prevalence of cancer is increasing, necessitating new additions to traditional treatments and diagnoses to address shortcomings such as ineffectiveness, complications, and high cost. In this context, nano and microparticulate carriers stand out due to their unique properties such as controlled release, higher bioavailability, and lower toxicity. Despite their popularity, they face several challenges including rapid liver uptake, low chemical stability in blood circulation, immunogenicity concerns, and acute adverse effects. Cell-mediated delivery systems are important topics to research because of their biocompatibility, biodegradability, prolonged delivery, high loading capacity, and targeted drug delivery capabilities. To date, a variety of cells including blood, immune, cancer, and stem cells, sperm, and bacteria have been combined with nanoparticles to develop efficient targeted cancer delivery or diagnosis systems. The review paper aimed to provide an overview of the potential applications of cell-based delivery systems in cancer therapy and diagnosis.

Recent advances in design and applications of biomimetic self-assembled peptide hydrogels for hard tissue regeneration.

ABSTRACT: The development of natural biomaterials applied for hard tissue repair and regeneration is of great importance, especially in societies with a large elderly population. Self-assembled peptide hydrogels are a new generation of biomaterials that provide excellent biocompatibility, tunable mechanical stability, injectability, trigger capability, lack of immunogenic reactions, and the ability to load cells and active pharmaceutical agents for tissue regeneration. Peptide-based hydrogels are ideal templates for the deposition of hydroxyapatite crystals, which can mimic the extracellular matrix. Thus, peptide-based hydrogels enhance hard tissue repair and regeneration compared to conventional methods. This review presents three major self-assembled peptide hydrogels with potential application for bone and dental tissue regeneration, including ionic self-complementary peptides, amphiphilic (surfactant-like) peptides, and triple-helix (collagen-like) peptides. Special attention is given to the main bioactive peptides, the role and importance of self-assembled peptide hydrogels, and a brief overview on molecular simulation of self-assembled peptide hydrogels applied for bone and dental tissue engineering and regeneration.

Single-chain antibody-decorated Au nanocages@liposomal layer nanoprobes for targeted SERS imaging and remote-controlled photothermal therapy of melanoma cancer cells.

The development of theranostic platforms combining surface-enhanced Raman spectroscopy (SERS) imaging with NIR-stimulated photothermal therapy (PTT) is of utmost importance for the precise diagnosis and selective treatment of cancers, especially in superficial solid tumors. For this purpose, a versatile theranostic nanoprobe of liposomal layer-coated Au nanocages (AuNCs) was decorated with an anti-MUC18 single-chain antibody (scFv). 4-mercapto benzoic acid (p-MBA)-labeled AuNCs (p-AuNCs) were coated by a liposomal layer (p-AuNCs@lip), followed by conjugating anti-MUC18 scFv via post-insertion method to form immuno-liposomal layer-coated AuNCs (p-AuNCs@scFv-lip). Physicochemical characterizations of the p-AuNCs@scFv-lip were investigated by transmission electron microscopy (TEM) and UV-vis and Raman spectroscopy. Furthermore, the targeting ability and theranostic efficiency of the nanoprobe were evaluated for specific diagnosis and treatment of cancerous melanoma cells by flow cytometry, SERS mapping, and live/dead assay. The formation of lipid layer on p-AuNCs surface was confirmed by TEM imaging. After decorating the liposomal layer with scFv, a relevant red shift was observed in the UV-vis spectrum. Moreover, p-AuNCs@lip presented characteristic peaks in the Raman spectrum, which exhibited only a minor change after scFv conjugation (p-AuNCs@scFv-lip). Interestingly, the cellular uptake of AuNCs@scFv-lip by A375 cell line (MUC18+) showed a 24-fold enhancement compared with SKBR3 cells (MUC18-). AuNCs@scFv-lip specifically identified A375 cells from SKBR cells via SERS mapping and effectively killed A375 cells through the PTT mechanism. Taken together, this theranostic platform can provide a promising tool for both in situ diagnosis and remote-controlled thermal ablation of cancer cells.

Antibody-guided nanomedicines as novel breakthrough therapeutic, diagnostic and theranostic tools.

Recent advances in nanotechnology, such as the development of various types of nanoparticles and hybrid nanomaterials, have revolutionized nanomedicine. The small size, customizable surface, enhanced solubility, and multi-functionality endow the nanoparticles with an ability to interact with complex cellular and biological functions in new ways. Furthermore, these systems can deliver drugs to specific tissues and provide a targeted therapy. For this purpose, different categories of molecules, particularly antibodies, have been used as ligands. Antibody-conjugated nanomaterials can significantly enhance the efficiency of nanomedicines, especially in the field of cancer. This review is focused on three major medical applications of antibody-conjugated nanomaterials, namely, therapeutic, diagnostic and theranostic applications. To provide comprehensive information on the topic and an overview of these hybrid nanomaterials for biomedical applications, a brief summary of nanomaterials and antibodies is given. Moreover, the review has depicted the potential applications of antibody-conjugated nanomaterials in different fields and their capabilities to empower nanomedicine, particularly in relation to the treatment and detection of malignancies.