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Working group 2 (WG2) of the Asia Partnership Conference of Regenerative Medicine has discussed eligibility of mesenchymal stromal cells (MSCs) as starting cells for the manufacture of cell therapy products, and comparability before and after changes in their manufacturing process. Asian countries and regions have their own regulations on the quality of starting cells, and these regulations are not harmonized. As cell therapy products are being developed across countries and regions, we propose a risk-based approach based on donor location, window period of virus test, and additional virus tests on the master cell bank to fill the gaps in regulation while controlling the risk of viral contamination. Moreover, a standard procedure of comparability assessment after changes in the manufacturing process of MSC-based products does not exist. The WG2 discussed points of comparability assessment specifically for MSC-based products considering the similarities and differences with parallel assessments for protein and polypeptide products, which are within the scope of the International Council for Harmonization Q5E guideline. We also summarize possible characterization procedures for MSC-based products and report our discussion on stability evaluations under accelerated and stress conditions for comparability assessment of cell therapy products.

Considering higher risks of candidates for cardiac regenerative therapy with compromised cardiac function, it is anticipated to develop less invasive surgical procedures. In the present study, we aimed to develop a prototype of totally endoscopic cell sheet delivery device and evaluate the surgical technique for epicardial cell sheet placement using three-dimensional (3D) printed simulators based on human computed tomography data.

We designed an endoscopic cell sheet delivery device with outer and inner frame with self-expandable applicator which can be opened in thoracic cavity. We launched spout line to provide liquids on the applicator surface and tension line to gently bend the applicator dorsally. We prepared human mesenchymal stem cell (MSC) sheets and compared wet/dry conditions of 3D printed heart/porcine heart and applicator to identify suitable conditions for cell sheet transplantation. Finally we validated the feasibility of endoscopic transplantation to anterior and lateral wall of left ventricle using 3D printed simulators.

Moist condition of both 3D printed heart/porcine heart surface and applicator at transplantation yielded highest successful rate (100%, p=0.0197). For both endoscopic transplantation sites, MSC sheets were successfully deployed. The procedure duration was 157±23s for anterior wall and 123±13s for the lateral wall in average, respectively.

We developed a novel prototype of endoscopic cell sheet delivery device for minimally-invasive cardiac regenerative therapy utilizing a 3D printed simulator. The commercialization of the prototype may provide a safe minimally-invasive method to deliver potential cardiac regenerative therapy in the future.

We developed a novel prototype of endoscopic cell sheet delivery device for minimally-invasive cardiac regenerative therapy utilizing a 3D printed simulator. The commercialization of the prototype may provide a safe minimally-invasive method to deliver potential cardiac regenerative therapy in the future.

In the development of cell therapy products for human use, studies on the biodistribution of transplanted cells in animals are important for assessing the safety and efficacy of these products. Although a few reports have described the biodistribution of human cells in animals using

-based-polymerase chain reaction (Alu-PCR), most have used genomic DNA or synthetic oligonucleotide as calibrators, as opposed to actual cells. In addition, bioanalytical variability in the quantification of cells with respect to specificity, selectivity, accuracy, and precision, has not been evaluated. Accordingly, in this study, we validated the utility of this bioanalytical method for human T cells in mice to establish assay performance using cells as a calibrator.

A standard curve was constructed for the addition of cell lysates to mouse tissues and blood, and DNA was extracted. Alu-PCR was applied for the quantification of human peripheral blood CD8

T cells in mice. To determine assay performance, we evaluated accurac cells in animals without the necessity of cell labeling. The data presented herein will be useful for standardizing bioanalytical approaches in biodistribution studies of cell therapy products.

The Alu-PCR technique developed in this study showed sufficient specificity and sensitivity in detecting human peripheral blood CD8+ T cells in mice. This technique, which targets the primate-specific Alu gene, is applicable for quantifying transplanted human cells in animals without the necessity of cell labeling. The data presented herein will be useful for standardizing bioanalytical approaches in biodistribution studies of cell therapy products.The study of regenerative dentistry receives a fast growing interest. The potential ability of the dentin-pulp complex to regenerate is both promising and perplexing. To answer the challenging nature of the dental environment, scientists have developed various combinations of biomaterial scaffolds, stem cells, and incorporation of several growth factors. One of the crucial elements of this tissue engineering plan is the selection and fabrication of scaffolds. However, further findings suggest that cell behavior hugely depends on mechanical signaling. Nanotopography modifies scaffolds to alter cell migration and differentiation. However, to the best of the author’s knowledge, there are very few studies addressing the correlation between nanotopography and dentin-pulp complex regeneration. Therefore, this article presents a comprehensive review of these studies and suggests a direction for future developments, particularly in the incorporation of nanotopography design for dentin-pulp complex regeneration.

Growth factors are crucial bioactive molecules invitro and invivo. RIP kinase inhibitor Among them, basic fibroblast growth factor (bFGF) has been used widely for various applications such as cell culture and regenerative medicine. However, bFGF has extremely poor stability in aqueous solution; thus, it is difficult to maintain its high local concentration. Heparin-conjugated materials have been studied recently as promising scaffold-immobilizing growth factors for biological and medical applications. The previous studies have focused on the local concentration maintenance and sustained release of the growth factors from the scaffold.

In this paper, we focused on the biological stability of bFGF immobilized on the heparin-conjugated collagen (hep-col) scaffold. The stability of the immobilized bFGF was quantitatively evaluated at physiological temperature (37°C) using cell culture and ELISA.

The immobilized bFGF had twice higher stability than the bFGF solution. Furthermore, the hep-col scaffold was able to immobilize not only bFGF but also other growth factors (i.