Bone-Targeted Exosome Modification Service

The skeletal system consists of bones, joints, and ligaments, including bone, cartilage, fibrous connective tissue, blood vessels, blood, and nerve tissue, and is essential for the structure and support of the body. If there is a problem with the skeletal system of the human body, it will have a great impact on many aspects such as movement, activity, and hematopoiesis. Common bone diseases include osteoporosis (OP), osteoarthritis (OA), and malignant tumors. Precision therapy of bone diseases generally requires invasive surgical procedures to implant drugs to maintain effective drug concentrations in bone. However, this invasive implant still lacks specific targeting. Therefore, specific drug delivery systems that actively target bone are very important. Exosomes are natural novel nano-delivery vehicles. The surface modification of exosomes can be artificially endowed with cell or tissue specificity. Creative Biolabs can construct engineered exosomes that can target bone, providing a platform and research ideas for this problem.

Engineered Exosomes Modified with Bone-Targeting Peptides

Due to its high affinity to low-crystalline hydroxyapatite and calcium phosphate on the bone-forming surface, the validated bone-targeting peptide, a polypeptide consisting of 6 repeating aspartate-serine-serine sequences (DSS6), can be modified on exosomes for bone-targeted drug delivery. Phospholipid molecule-DSS6 can be inserted into the exosomal phospholipid bilayer through hydrophobicity, resulting in bone-targeted exosomes (DSS6-Exo) with DSS6 on the surface. Previous studies have shown that DSS6-Exo loaded with siRNA can promote the bone formation of osteoblasts and angiogenesis. This indicates that DSS6-Exo is expected to be used in the precise treatment of OP.

Fig.1 Preparation of BT-Exo-siShn3 and the therapeutic mechanism. (Cui, 2022)

Engineered Exosomes Modified with Cartilage -Targeting Peptides

The dense connective tissue formed by the extracellular matrix of chondrocytes has been an obstacle to drug delivery by exosomes. Excitingly, researchers have screened out a chondrocyte affinity peptide (CAP, sequence: DWRVIIPPRPSA) through phage display technology, which can transport drugs into chondrocytes. Furthermore, the researchers have achieved fusion expression of CAP and lysosome-associated membrane glycoprotein 2b (Lamp2b) to construct CAP-Exo targeting chondrocytes. CAP-Exo encapsulated with miR-140 can play the biological role of miR-140 in the deep chondrocyte region through joint injection, inhibit cartilage degradation proteases, and alleviate the progression of OA.

Fig.2 Engineered exosomes for cartilage repair. (Liang, 2020)

Bone-targeted exosomes can specifically guide therapeutic drugs to target tissues, showing their great potential for clinical translation. Creative Biolabs is committed to the development and clinical transformation of exosome technology and can provide one-stop services for the construction, extraction, and efficacy verification of engineered exosomes. Please feel free to contact us with your needs. Our professionals will provide customers with personalized solutions and a full range of services.

References

Cui, Y.; Guo, Y.; et al. A bone-targeted engineered exosome platform delivering siRNA to treat osteoporosis. Bioactive Materials. 2022. 10:207-221.
Liang, Y.; Xu, X.; et al. Chondrocyte-targeted microRNA delivery by engineered exosomes toward a cell-free osteoarthritis therapy. ACS Applied Materials & Interfaces. 2020. 12(33):36938-36947.

Plant Exosome Isolation