Current Regenerative Medicine Formerly: Recent Patents on Regenerative Medicine - Volume 7, Issue 1, 2017

The analytical review is devoted to the current state of the world problem of restoring the anatomical and functional integrity of the spinal cord after trauma in experimental animal models and humans. The review includes the epidemiology and pathophysiology of spinal cord injury (SCI), the use of stem cells for local transplantation in the central nervous system, including embryonic or induced pluripotent stem cells or the precursors of neuronal and glial cells. An important place in the review is devoted to the use of neuronal trophic factors in the concept of reconstructive therapy of spinal cord injuries. The authors singled out the experimental and clinical directions of the restoration of the conduction pathways and functions of the spinal cord when it is damaged placing emphasis on the combined use of cellular, neuronal trophic ingredients based on the most modern biodegradable implants with the properties of target molecule system delivery. Considering the fact that obtaining reprogrammed neuronal cells from IPSCh take a long time with a small output of specialized cell mass, the authors of the review give examples of modern promising technologies for solving this problem. The analysis of biodegradable matrices for cell transplantation into the area of spinal cord injury focuses on the role of chitosan biopolymer as a promising material for regenerative medicine, in particular for the elimination of spinal cord injury. The authors' own results point to the successful experimental use of cellular collagen-chitosan matrices in the reconstruction of the spinal cord during its full transection. A separate section is devoted to the role of angiogenesis factors in the restoration of spinal cord functions and the contribution of chitosan polymers in the formation of therapeutic angiogenesis in spinal cord injury. The authors of the article draw attention to recommendations for basic and clinical trials of cellular products, biological surveillance, transparency of manipulation and ethics, presented by the International Campaign for Cures of Spinal Cord Injury Paralysis (ICCP) and the International Society for Stem Cell Research (ISSCR).

The human endometrium is a very dynamic tissue undergoing an extraordinary growth during pregnancy and, in a cyclic manner, during the reproductive life of each woman. Endometrial stem cells (ESCs), undifferentiated auto-renewable cells able to generate daughter cells showing a higher level of differentiation, play a fundamental role in endometrial regeneration and repair. Therefore, they have a great therapeutic potential in many diseases and research fields. However, recent data suggest that an irregular function of ESCs can contribute to the pathogenesis of endometriosis and other disorders. In addition, ESCs have also been found in human leiomyomas and malignant tumours, and could be involved in their development. In this review we analyze the enormous regenerative potential of endometrium, which is, unfortunately, not exempted from its negative effects. This coexists with the good one as two faces of the same coin and constitutes the risk behind the fundamental protective and regenerative mechanisms to defend reproduction, and therefore the miracle of life itself.

Mesenchymal stem cells (MSCs) are pluripotent stem cells isolated from adipose tissue (AD-MSCs), bone marrow (BM-MSCs) and umbilical cord (UC-MSCs). Due to their ability to differentiate into multiple cell types, homing to injury sites and immunosuppressive properties have been proposed as a promising option in regenerative medicine. Studies have shown that the majority of regenerative effects of MSCs are exerted through their paracrine effects. Moreover, it has been shown that some of the regenerative functions of MSCs are mediated by exosomes, and MSC-derived exosomes play a vital role in the treatment of diseases. Since angiogenesis is a crucial process in the regeneration of damaged tissues, this review discusses the angiogenic capabilities of MSC-derived exosomes (MSC-DEs) and their mechanisms that are responsible for the control of angiogenesis in wound healing, cardiovascular diseases (CVDs) and bone defects.

Background: Chondrogenic differentiation of human embryonic stem cells (hESCs) has been investigated by maintenance of 3-dimensional cultures in the presence of various exogenous growth factors added during defined stages of culture, or in cocultures with primary chondrocytes, making the cultivation process rather complex. Thus, there is a need for easier and more handy expansion and differentiation protocols. Objective: The present study is aimed to investigate the potential of hESCs for chondrogenic differentiation in simpler culture conditions. Methods: The hESCs were directly cultured for 3 weeks on feeder-free gelatin-coated plates in chondrocyte culture medium without any growth factor supplements after 6-day culture on feeder-free gelatin- coated plate with conditioned medium. Results: Immunocytochemical and gene expression analyses indicated that these human directly differentiated cells (hDDCs), which derived from the hESCs, abundantly expressed Sox9, aggrecan, and procollagen α1(II) mRNAs. Upon further passaging, the hDDCs behaved similarly to primary chondrocytes, although the aggrecan mRNA expressions were maintained at a relatively constant level throughout passaging. The procollagen α1(II) mRNAs expression was high in the beginning of the hDDC culture, but declined upon further passaging, which is typical for the primary chondrocytes. The hDDCs could be easily expanded in the monolayer culture using chondrocyte culture medium. Differentiation assays showed that the hDDCs could be differentiated towards chondrocytes, but not adipocytes or osteoblasts. Conclusion: Our data suggests that the chondrogenic gene expression could be induced in the directly differentiated hESCs without a need for chondrocyte coculture. In contrast, no osteogenic or adipogenic differentiation was observed.