Reverse-engineered silk hydrogels for cell and drug delivery

Silk is an important biopolymer for (bio)medical applications because of its unique and highly versatile structure and its robust clinical track record in human medicine. Silk can be processed into many material formats, including physically and chemically cross-linked hydrogels that have almost limitless applications ranging from tissue engineering to biomedical imaging and sensing. This concise review provides a detailed background of silk hydrogels, including silk structure–function relationships, biocompatibility and biodegradation, and it explores recent developments in silk hydrogel utilization, with specific reference to drug and cell delivery. We address common pitfalls and misconceptions while identifying emerging opportunities, including 3D printing

Impact of 3D cell culture on bone regeneration potential of mesenchymal stromal cells

As populations age across the world, osteoporosis and osteoporosis-related fractures are becoming the most prevalent degenerative bone diseases. More than 75 million patients suffer from osteoporosis in the US, the EU and Japan. Furthermore, it is anticipated that the number of patients affected by osteoporosis will increase by a third by 2050. Although conventional therapies including bisphosphonates, calcitonin and oestrogen-like drugs can be used to treat degenerative diseases, they are often associated with serious side effects including the development of oesophageal cancer, ocular inflammation, severe musculoskeletal pain, and osteonecrosis of the jaw. The use of autologous mesenchymal stromal cells/mesenchymal stem cells (MSCs) is a possible alternative therapeutic approach to tackle osteoporosis while overcoming the limitations of traditional treatment options. However, osteoporosis can cause a decrease in the numbers of MSCs, induce their senescence, and lower their osteogenic differentiation potential. Three-dimensional (3D) cell culture is an emerging technology that allows a more physiological expansion and differentiation of stem cells compared to cultivation on conventional flat systems. This review will discuss current understanding of the effects of different 3D cell culture systems on proliferation, viability, osteogenic differentiation, as well as on the immunomodulatory and anti-inflammatory potential of MSCs

The use of 3D printed microporous-strut polycaprolactone scaffolds for targeted local delivery of chemotherapeutic agent for breast cancer application

Local recurrent cancer remains a challenge for breast cancer patients receiving implants after mastectomy or lumpectomy. The use of radiotherapy and/or systemic administration of chemotherapeutic agents post-surgery can be beneficial yet they also kill healthy cells and introduce systemic side effects. In this study, a new method was introduced to utilize 3D printed microporous polycaprolactone (PCL) scaffolds as a multifunctional device—an implant and a drug delivery vehicle for targeted local delivery. Their microporous structure was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The dependence of release profiles of Doxorubicin (DOX) loaded scaffolds on pH and ionic strength of the environment was demonstrated. Lastly, their chemotherapeutic effect was characterized by in vitro. Overall, the results demonstrated the utility of the microporosity and surface charge of PCL scaffolds to immobilize DOX for local, targeted drug delivery