Extracellular Matrix Scaffolds - A Tissue-Specific Bioactive Niche for Stem Cells in Regenerative Therapy

Aiming to restore the normal function of diseased or injured tissues, regenerative therapy approaches are generally based on the engineering of complex tissue-mimicking grafts, encompassing biomaterial scaffolds, stem cells, or their combinations [1-4]. Due to the major role of stem cells in physiological regenerative mechanisms, regenerative therapies normally rely on either stem cells transplantation or stem cell recruitment from the neighboring tissue into the implanted scaffold

Clinical application of both amniotic membranes and adipose derived mesenchymal stem cells in a cat with a large skin defect

Surgical procedures on large skin defects can be challenging in the short term due to the size of the lesion, infection, and tissue defect. A regenerative therapy for skin wounds has been applied to promote the healing process. An 8-month-old, Korean domestic short-haired female cat, weighing 3 kg, was rescued with extensive defects on the right flank to right inguinal region caused by bite wounds. In this case, amniotic membranes and adipose-derived mesenchymal stem cells were used as the regenerative therapy to treat the large skin defect rather than a surgical intervention alone. To the best of our knowledge, this is the first report of a case with of a large skin defect treated by applying allogeneic amniotic membranes and allogeneic mesenchymal stem cells to a cat.

The Present State and Future Perspectives of Cardiac Regenerative Therapy Using Human Pluripotent Stem Cells

The number of patients with heart failure (HF) is increasing with aging in our society worldwide. Patients with HF who are resistant to medication and device therapy are candidates for heart transplantation (HT). However, the shortage of donor hearts is a serious issue. As an alternative to HT, cardiac regenerative therapy using human pluripotent stem cells (hPSCs), such as human embryonic stem cells and induced pluripotent stem cells, is expected to be realized. Differentiation of hPSCs into cardiomyocytes (CMs) is facilitated by mimicking normal heart development. To prevent tumorigenesis after transplantation, it is important to eliminate non-CMs, including residual hPSCs, and select only CMs. Among many CM selection systems, metabolic selection based on the differences in metabolism between CMs and non-CMs is favorable in terms of cost and efficacy. Large-scale culture systems have been developed because a large number of hPSC-derived CMs (hPSC-CMs) are required for transplantation in clinical settings. In large animal models, hPSC-CMs transplanted into the myocardium improved cardiac function in a myocardial infarction model. Although post-transplantation arrhythmia and immune rejection remain problems, their mechanisms and solutions are under investigation. In this manner, the problems of cardiac regenerative therapy are being solved individually. Thus, cardiac regenerative therapy with hPSC-CMs is expected to become a safe and effective treatment for HF in the near future. In this review, we describe previous studies related to hPSC-CMs and discuss the future perspectives of cardiac regenerative therapy using hPSC-CMs.

Current progress of rehabilitative strategies in stem cell therapy for spinal cord injury: a review

Stem cell-based regenerative therapy has opened an avenue for functional recovery of patients with spinal cord injury (SCI). Regenerative rehabilitation is attracting wide attention owing to its synergistic effects, feasibility, non-invasiveness, and diverse and systemic properties. In this review article, we summarize the features of rehabilitation, describe the mechanism of combinatorial treatment, and discuss regenerative rehabilitation in the context of SCI. Although conventional rehabilitative methods have commonly been implemented alone, especially in studies of acute-to-subacute SCI, the combinatorial effects of intensive and advanced methods, including various neurorehabilitative approaches, have also been reported. Separating the concept of combined rehabilitation from regenerative rehabilitation, we suggest that the main roles of regenerative rehabilitation can be categorized as conditioning/reconditioning, functional training, and physical exercise, all of which are indispensable for enhancing functional recovery achieved using stem cell therapies.

Heart stem cells: hope or myth?

The search and study of endogenous heart repair remains an urgent issue in modern regenerative medicine. It is generally accepted that the human heart has a limited regenerative potential, but recent studies show that functionally significant regeneration is possible. However, the mechanisms underlying these processes remain poorly understood. In the heart, there are populations of resident mesenchymal cells that have some properties of stem cells that carry certain markers, such as c-kit+, Sca-1, etc. The ability of these cells to differentiate directly into cardiomyocytes remains controversial, but their use in clinical trials has shown improved cardiac function in patients with myocardial infarction. Currently, approaches are being developed to use, mainly, induced pluripotent stem cells as a promising regenerative therapy, but the cardioprotective role of cardiac mesenchymal cells remains the subject of active study due to their paracrine signaling.

Immunomodulation and Regenerative Capacity of MSCs for Long-COVID

The rapid mutation of the SARS-CoV-2 virus is now a major concern with no effective drugs and treatments. The severity of the disease is linked to the induction of a cytokine storm that promotes extensive inflammation in the lung, leading to many acute lung injuries, pulmonary edema, and eventually death. Mesenchymal stem cells (MSCs) might prove to be a treatment option as they have immunomodulation and regenerative properties. Clinical trials utilizing MSCs in treating acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) have provided a basis in treating post-COVID-19 patients. In this review, we discussed the effects of MSCs as an immunomodulator to reduce the severity and death in patients with COVID-19, including the usage of MSCs as an alternative regenerative therapy in post-COVID-19 patients. This review also includes the current clinical trials in utilizing MSCs and their potential future utilization for long-COVID treatments.