Stem cell sources and therapeutic approaches for central nervous system and neural retinal disorders

Abstract

<jats:p>✓ In the past decades, stem cell biology has made a profound impact on our views of mammalian development as well as opened new avenues in regenerative medicine. The potential of stem cells to differentiate into various cell types of the body is the principal reason they are being explored in treatments for diseases in which there may be dysfunctional cells and/or loss of healthy cells due to disease. In addition, other properties are unique to stem cells; their endogenous trophic support, ability to home to sites of pathological entities, and stability in culture, which allows genetic manipulation, are also being utilized to formulate stem cell–based therapy for central nervous system (CNS) disorders. In this review, the authors will review key characteristics of embryonic and somatic (adult) stem cells, consider therapeutic strategies employed in stem cell therapy, and discuss the recent advances made in stem cell–based therapy for a number of progressive neurodegenerative diseases in the CNS as well as neuronal degeneration secondary to other abnormalities and injuries. Although a great deal of progress has been made in our knowledge of stem cells and their utility in treating CNS disorders, much still needs to be elucidated regarding the biology of the stem cells and the pathogenesis of targeted CNS diseases to maximize therapeutic benefits. Nonetheless, stem cells present tremendous promise in the treatment of a variety of neurodegenerative diseases.</jats:p>

Lumbar Intraspinal Injection of Neural Stem Cells in Patients with Amyotrophic Lateral Sclerosis: Results of a Phase I Trial in 12 Patients

“…Advances in stem cell biology have raised the question of whether cellular therapies may be a viable option for the treatment of ALS, either by replacing diseased cell populations directly or by introducing a cell population that can be supportive to the motor neurons affected by the disease process [1]. Several cell types have been proposed for testing in ALS, including mesenchymal stem cells (MSCs) derived from bone marrow, glial progenitor cells, and spinal cord-derived neural progenitor cells [2][3][4]. Each of these cell types has preclinical data both in vitro and in animal models supporting their potential as therapeutic options for ALS.…”

Therapeutic Effect of Human Umbilical Cord Multipotent Mesenchymal Stromal Cells in a Rat Model of Stroke

“…Stem cells present tremendous potential in the treatment of a variety of neurodegenerative diseases (2). Multipotent mesenchymal stromal cells (MSC), which are previously known as mesenchymal stem cells (3), have become a promising candidate for cell-based therapy because of their multipotency and immune tolerant feature (4,5).…”

Molecular Imaging for Stem Cell Transplantation in Neuroregenerative Medicine

“…On the other hand, although many studies have aimed to replace necrotic or dysfunctional neural tissue by the direct implantation of stem cells following CNS injury, only little functional recovery has been observed until now [11] . A more realistic goal for stem cell therapy to restore injured CNS tissue might therefore be the implantation of genetically modified stem cell populations in order to produce neurotrophic factors (like brain-derived neurotrophic factor, neurotrophin-3 or glial cell line-derived neurotrophic factor), with the potential to enhance survival of the existing neurons and endogenous neuroregeneration [3,11] .…”

“…A more realistic goal for stem cell therapy to restore injured CNS tissue might therefore be the implantation of genetically modified stem cell populations in order to produce neurotrophic factors (like brain-derived neurotrophic factor, neurotrophin-3 or glial cell line-derived neurotrophic factor), with the potential to enhance survival of the existing neurons and endogenous neuroregeneration [3,11] . By this approach, stem cells can be genetically manipulated in vitro to express desired transgenes for improved expandability, as well as for delivery of toxic payloads.…”