Some small molecules are capable of alteration of many essential cellular processes such as apoptosis, proliferation and differentiation. The anticonvulsant and antiepileptic drug, VPA, for example, can mainly exert these effects through epigenetic modifications such as direct and indirect inhibition of histone deacetylases (HDAC) and DNA methyl transferases, respectively.
Umbilical cord blood (CB) is a natural source of hematopoietic stem cells (HSCs) and is an accepted alternative to bone marrow for transplantation purposes in a variety of diseases such as leukemia, congenital immunodeficiencies, hereditary metabolic disorders,
hemoglobinopathies, and bone marrow failure syndromes (1–4). Gluckman et al. reported the first successful CB transplantation for Fanconi anemia in 1989 (5).
The interior of the amniotic sac is filled with amniotic fluid, which allows the fetus to move freely in the womb and absorbs physical forces of mechanical injury. The amniotic sac also participates in the metabolism of the fetus, allowing for nutrient transport and contributing to maternal-fetal tolerance.
Stem cells (SCs) have been considered among the most promising cell populations for regenerative medicine. SCs can be defined as pluripotent or multipotent cells which have the capability of self-renewal and the potential to differentiate into several lineages. SCs can be classified into embryonic, fetal or adult stem cells that are further divided mainly into hematopoietic and mesenchymal stem cells (MSCs) .
Chronic liver disease (CLD) results in the development of chronic hepatic wound healing, characterised by persistent liver inflammation and the accumulation of extracellular matrix proteins (ECM), collectively described as fibrosis [1, 2]. Crucial to the pathogenesis of liver fibrosis are hepatic stellate cells (HSCs) and macrophages [3, 4].
Cellular therapy has evolved quickly over the past decade, with valuable experience gained in both preclinical research and clinical trials. One group of adult stem cells, mesenchymal stem cells (MSCs), has generated great interest in the fields of regenerative medicine and immunotherapy due to their unique biological properties.
The first reported clinical use of perinatal-derived biomaterials was at Johns Hopkins over a century ago in 1910 as an aid for dermal wound healing. In recent years, both clinical and research applications of these biomaterials have increased in scope to include roles in tissue engineering, regenerative medicine, and cell-based therapies, especially in the field of orthobiologics.
The study of neural development draws on both neuroscience and developmental biology to describe the cellular and molecular mechanisms by which complex nervous systems emerge during embryonic development and throughout life. Some of the landmarks of the neural development include the birth and differentiation of neurons from stem cell precursors, their migration, protrusions of axons and dendrites, and finally generation of synapses between these axons.
The compensation of demyelination is one of promising approaches to overcome consequences of spinal cord injury (SCI). It is experimentally confirmed that after injury, the Schwann cells (SCs) migrate from the peripheral nervous system towards the site of injury and participate in axon remyelination .
Keloids are dermal tumors categorized by a group of unusual fibroblasts with excessive deposition of extracellular matrix components such as collagen, elastin, fibronectin, and proteoglycans. Clinically, keloids are characterized by a painful pruritic raised scar that grows beyond the boundary of the original margin of wounds.
Bone pathologies are the main causes of disability. With the increase in life expectancy, it is foreseeable that millions of people in many countries will be affected by diseases affecting the bones. The diseases affecting the bone, both acute, such as fractures, and chronic, i.e., osteoporosis and tumors, require treatments which involve the use of cells, growth factors and bone substitutes, as biomaterials/scaffolds, with biocompatibility, osteoinductive, and osteoconductive properties [1–3].
Tissue engineering involves functional biomaterial scaffolds and cells for restoring of damaged or diseased tissue. Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) can differentiate into several lineages, including adipose cells, chondrocytes, osteoblasts, neuronal cells, endothelial cells, cardiomyocytes, hepatocyte-like, and pancreatics beta cells [1-3].
There is still no precise definition for mesenchymal stem cells (MSCs) despite almost half a century having passed since the first isolation of plastic-adherent non-haematopoietic bone marrow (BM) cells capable of clonal expansion [1, 2]. There is also no consensus on nomenclature, with terms including mesenchymal stem cell, mesenchymal stromal cell and multipotent mesenchymal stromal cell – preferred by the International Society for Cell Therapy (ISCT) – all being known by the abbreviation MSC .
In general, the ‘stemness’ of cells can be defined as the most primitive cell state that combines two inseparable properties: the ability of self-renewal and the ability to differentiate. More accurately, stem cells (SCs) can generate daughter cells that are identical to their mother cells (self-renewal), as well as progenitor/precursor cells with more restricted potential (differentiation) [1–4].
The development of new treatments for bone-related diseases resulting from trauma or pathophysiological age-, sex- or infection-associated bone resorption has become a priority in the field of regenerative medicine [1–4]. In this context, autologous cell-based therapy has been presented as a promising approach to promote bone regeneration in both pre-clinical and clinical settings [5–8].
The development of tissue engineering has made it an attractive method with great repairing potential for tissue defects. Bone tissue engineering techniques based on autogenously cell/tissue transplantation would eliminate problems of donor compatibility, limitation of autograft implantation, pathogen transfer and immune response of allograft bone transplantation .
Of the diverse range of scaffolds available for use in maxillofacial surgery and dentistry, autografts have been reported to be the “gold standard” with respect to bone grafting procedures . However, harvesting of autografts, usually from the iliac crest, requires surgical intervention, which is associated with additional risks of blood loss, infection, and morbidity, and supply is limited [2, 3].
Stem cell and tissue engineering (SC&TE) are modern technologies that have been controversial from their initial reporting. Today they still are, despite years of successful research. This controversy lives among the general public and law makers, as well as some medical care givers, researchers, scientists and eventually among public decision makers .