Future research and therapeutic applications of human stem cells: general, regulatory, and bioethical aspects

Abstract

There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases). Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell) and the efficacy (maximum effect) and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further aggravated.

Corneal endothelium: developmental strategies for regeneration

“…Subcutaneous adipose tissue is more abundant and often waste product in liposuction cosmetic and therapeutic type. 97,98 The ability of adult stem cells to secrete different types of molecules with anti-apoptotic, immunomodulatory, angiogenic, chemoattractant, and anti-scarring properties provides the basis for their use in regenerative medicine. 99 Investigative therapies have been used in clinical trials with some designed to treat autoimmune diseases, including multiple sclerosis, lupus erythematosus, and Crohn's disease, as well as diabetes mellitus, myocardial infarction, different types of cancer, neurological disorders, and ocular surface diseases.…”

Stem Cells Cloning Prons & Cons

“…Strategies to circumvent these problems, such as the expression of immune systemmodulating genes by stem cells, creation of chimeric, immunotolerable bone marrow or suppression of HLA genes have been suggested. In this context, nuclear transfer technology has been recently extended to human embryonic stem cells [7].…”

“…Additionally undifferentiated embryonic stem cells have the potential to form a type of cancer called a teratocarcinoma. Safety precautions are therefore necessary, and currently, protocols are being developed to allow the complete depletion of any remaining undifferentiated embryonic stem cells [6,7].…”

Stem Cell Therapy for Amyotrophic Lateral Sclerosis

“…MSCs can be relatively easily obtained from adult tissues, and their application does not pose substantial ethical issues [58,59], and because ALS does not influence MSC expansion and differentiation [60], the cells can be extracted from patients themselves, thus avoiding immune rejection. So, MSCs seem to be an attractive candidate for ALS cell therapy.…”