6 research outputs found
Engineering Neurotoxin-Functionalized Exosomes for Targeted Delivery to the Peripheral Nervous System
The administration of therapeutics to peripheral nerve tissue is challenging due to the complexities of peripheral neuroanatomy and the limitations imposed by the blood–nerve barrier (BNB). Therefore, there is a pressing need to enhance delivery effectiveness and implement targeted delivery methods. Recently, erythrocyte-derived exosomes (Exos) have gained widespread attention as biocompatible vehicles for therapeutics in clinical applications. However, engineering targeted Exos for the peripheral nervous system (PNS) is still challenging. This study aims to develop a targeted Exo delivery system specifically designed for presynaptic terminals of peripheral nerve tissue. The clostridium neurotoxin, tetanus toxin-C fragment (TTC), was tethered to the surface of red blood cell (RBC)-derived Exos via a facile and efficient bio-orthogonal click chemistry method without a catalyst. Additionally, Cyanine5 (Cy5), a reactive fluorescent tag, was also conjugated to track Exo movement in both in vitro and in vivo models. Subsequently, Neuro-2a, a mouse neuronal cell line, was treated with dye-labeled Exos with/without TTC in vitro, and the results indicated that TTC-Exos exhibited more efficient accumulation along the soma and axonal circumference, compared to their unmodified counterparts. Further investigation, using a mouse model, revealed that within 72 h of intramuscular administration, engineered TTC-Exos were successfully transported into the neuromuscular junction and sciatic nerve tissues. These results indicated that TTC played a crucial role in the Exo delivery system, improving the affinity to peripheral nerves. These promising results underscore the potential of using targeted Exo carriers to deliver therapeutics for treating peripheral neuropathies
A targeted near-infrared nanoprobe for deep-tissue penetration and imaging of prostate cancer
Fluorescent guided surgery (FGS) has been highlighted as a potential to increase precision of
diseased tissue whilst minimising the removal of surrounding healthy tissue, particularly
relevant for increasingly prevalent prostate cancer (PCa). There remain challenges in the
design of imaging probes presenting high selectivity for tumour tissue, clear visualization and
minimal toxicity. Here we report the design and development of a novel NIR-nanoprobe and
evaluate its potential in penetration inside PCa tumour tissues. Prostate-specific membrane
antigen (PSMA) receptor-targeted near infrared emitting quantum dots (PSMA-NIR-QDot)
are demonstrated as deep tissue imaging agents for intraoperative navigation during surgery
and improving detection specificity for PCa. Probes were designed and synthesized by
conjugating functionalized amino-PEG QDots through a heterobifunctional linker to a DUPA
targeted polypeptide construct. Nanoprobes were evaluated in vitro in PSMA+ PCa cell lines
for specificity and affinity determined by flow cytometric analysis. The penetration efficacy
was tested further on large PCa 3D tumour spheroids (dia ~ 1.2 mm, width ~ 250 µm) by
deep tissue multiphoton imaging. The PSMA-NIR-Qdot was found to be an efficient deep
tissue penetrating intra-operative guided surgical tool with high affinity (KD = 15 nM) and
penetrative capacity. The results have been demonstrated in vitro in 2D and 3D tissue models,
mimicking cancer lesions in vivo. The presented deep-tissue imaging NIR nanoprobes target
prostatic lesions that (i) bind to PSMA+
tumour with sub-nanomolar affinity and high
specificity, (ii) show excellent safety profile in primary cell lines in vitro, and (iii) show high
penetrative capacity in 3D prostate tumour model (~ 250 µm tissue depth). These probes may
potentially offer vastly improved surgical accuracy for diseased tissue removal.</p
Novel solid-phase strategy for the synthesis of ligand-targeted fluorescent-labelled chelating peptide conjugates as a theranostic tool for cancer
In this article, we have successfully designed and demonstrated a novel continuous process for assembling targeting ligands, peptidic spacers, fluorescent tags and a chelating core for the attachment of cytotoxic molecules, radiotracers, nanomaterials in a standard Fmoc solid-phase peptide synthesis in high yield and purity. The differentially protected Fmoc-Lys-(Tfa)-OH plays a vital role in attaching fluorescent tags while growing the peptide chain in an uninterrupted manner. The methodology is versatile for solid-phase resins that are sensitive to mild and strong acidic conditions when acid-sensitive side chain amino protecting groups such as Trt (chlorotrityl), Mtt (4-methyltrityl), Mmt (4-methoxytrityl) are employed to synthesise the ligand targeted fluorescent tagged bioconjugates. Using this methodology, DUPA rhodamine B conjugate (DUPA = 2-[3-(1,3-dicarboxypropyl)ureido]pentanedioic acid), targeting prostate specific membrane antigen (PSMA) expressed on prostate, breast, bladder and brain cancers and pteroate rhodamine B, targeting folate receptor positive cancers such as ovarian, lung, endometrium as well as inflammatory diseases have been synthesized. In vitro studies using LNCaP (PSMA +ve), PC-3 (PSMA −ve, FR −ve) and CHO-β (FR +ve) cell lines and their respective competition experiments demonstrate the specificity of the newly synthesized bioconstructs for future application in fluorescent guided intra-operative imaging
Digital Light Processing 4D Printing of Poloxamer Micelles for Facile Fabrication of Multifunctional Biocompatible Hydrogels as Tailored Wearable Sensors
The lack of both digital light processing (DLP) compatible
and
biocompatible photopolymers, along with inappropriate material properties
required for wearable sensor applications, substantially hinders the
employment of DLP 3D printing in the fabrication of multifunctional
hydrogels. Herein, we discovered and implemented a photoreactive poloxamer
derivative, Pluronic F-127 diacrylate, which overcomes these limitations
and is optimized to achieve DLP 3D printed micelle-based hydrogels
with high structural complexity, resolution, and precision. In addition,
the dehydrated hydrogels exhibit a shape-memory effect and are conformally
attached to the geometry of the detection point after rehydration,
which implies the 4D printing characteristic of the fabrication process
and is beneficial for the storage and application of the device. The
excellent cytocompatibility and in vivo biocompatibility
further strengthen the potential application of the poloxamer micelle-based
hydrogels as a platform for multifunctional wearable systems. After
processing them with a lithium chloride (LiCl) solution, multifunctional
conductive ionic hydrogels with antifreezing and antiswelling properties
along with good transparency and water retention are easily prepared.
As capacitive flexible sensors, the DLP 3D printed micelle-based hydrogel
devices exhibit excellent sensitivity, cycling stability, and durability
in detecting multimodal deformations. Moreover, the DLP 3D printed
conductive hydrogels are successfully applied as real-time human motion
and tactile sensors with satisfactory sensing performances even in
a −20 °C low-temperature environment
Digital Light Processing 4D Printing of Poloxamer Micelles for Facile Fabrication of Multifunctional Biocompatible Hydrogels as Tailored Wearable Sensors
The lack of both digital light processing (DLP) compatible
and
biocompatible photopolymers, along with inappropriate material properties
required for wearable sensor applications, substantially hinders the
employment of DLP 3D printing in the fabrication of multifunctional
hydrogels. Herein, we discovered and implemented a photoreactive poloxamer
derivative, Pluronic F-127 diacrylate, which overcomes these limitations
and is optimized to achieve DLP 3D printed micelle-based hydrogels
with high structural complexity, resolution, and precision. In addition,
the dehydrated hydrogels exhibit a shape-memory effect and are conformally
attached to the geometry of the detection point after rehydration,
which implies the 4D printing characteristic of the fabrication process
and is beneficial for the storage and application of the device. The
excellent cytocompatibility and in vivo biocompatibility
further strengthen the potential application of the poloxamer micelle-based
hydrogels as a platform for multifunctional wearable systems. After
processing them with a lithium chloride (LiCl) solution, multifunctional
conductive ionic hydrogels with antifreezing and antiswelling properties
along with good transparency and water retention are easily prepared.
As capacitive flexible sensors, the DLP 3D printed micelle-based hydrogel
devices exhibit excellent sensitivity, cycling stability, and durability
in detecting multimodal deformations. Moreover, the DLP 3D printed
conductive hydrogels are successfully applied as real-time human motion
and tactile sensors with satisfactory sensing performances even in
a −20 °C low-temperature environment