Anti-NES monoclonal antibody, clone HU734

Regenerative strategies for human articular cartilage are still challenging despite the presence of resident progenitor cell population. Today, many efforts in the field of regenerative medicine focus on the use of platelet derivatives due to their ability to reactivate endogenous mechanisms supporting tissue repair. While their use in orthopedics continues, mechanisms of action and efficacy need further characterization. We describe that the platelet lysate (PL) is able to activate chondro-progenitor cells in a terminally differentiated cartilage tissue. Primary cultures of human articular chondrocytes (ACs) and cartilage explants were set up from donor hip joint biopsies and were treated in vitro with PL. PL recruited a chondro-progenitors (CPCs)-enriched population from ex vivo cartilage culture, that showed high proliferation rate, clonogenicity and nestin expression. CPCs were positive for in vitro tri-lineage differentiation and formed hyaline cartilage-like tissue in vivo without hypertrophic fate. Moreover, the secretory profile of CPCs was analyzed, together with their migratory capabilities. Some CPC-features were also induced in PL-treated ACs compared to fetal bovine serum (FBS)-control ACs. PL treatment of human articular cartilage activates a stem cell niche responsive to injury. These facts can improve the PL therapeutic efficacy in cartilage applications.

Electrospun nanofibrous scaffolds show huge potential to improve the neurological outcome in central nervous system disorders. In this study, we cultured mouse embryonic stem cells (mESCs) on an electrospun nanofibrous polylactic acid/Chitosan/Wax (PLA/CS/Wax) scaffold and surveyed the attachment, behavior, and differentiation of mESCs into neural cells. Differentiation in neural-like cells (NLCs) was investigated with a medium containing SB431542 as a small molecule and conjugated linolenic acid after 20 days. We used Immunocytochemistry and quantitative real-time polymerase chain reaction (RT-PCR) techniques to assess neural marker expression in differentiated cells. SEM imaging demonstrated that mESCs could strongly attach, stretch, and differentiate on PLA/CS/Wax scaffolds. MESCs that were cultured on PLA/CS/Wax scaffolds showed enhanced numbers of neural structures and neural markers including Nestin, NF-H, Tuj-1, and Map2 in neural induction medium compared to the control sample. These results revealed that electrospun PLA/CS/Wax scaffolds associated with the induction medium can assemble proper conditions for stem cell differentiation into NLCs. We hope that the development of new technologies in neural tissue engineering may pave a new avenue for neural tissue regeneration.