Stem Cell Therapy

Abstract

Stem cell therapy has partially been used for treatment of some diseases although the method is still under early stages of research. This method involves differentiation where stem cells are turned into specific cells which are then transplanted into patients with an aim of treating different injuries and diseases. The research and clinical trials on the use embryonic stem cells, MSCs (mesenchymal stem cells) and induced pluripotent stem cells therapy is expected to bring about significant benefits to patients suffering from different diseases. The use if stem cell therapy has raised concerns of failures due to lack of concrete research, ethical and risk issues related to harvesting and transplanting the differentiated cells.

Introduction

Stem- cell therapy refers to the use of stem cells in the prevention and treatment of diseases or conditions. The most widely used and well-established treatment on stem cell involve the blood stem cell transplantation for the treatment of immune system and blood diseases and conditions  or in restoration of blood system  after  treatment of certain cancers has been undertaken.  Majority of stem cell therapies are research in the earliest stages and are considered to be long way from being used for clinical purpose.  The clinical investigations by use of stem cells treatment products are addressing many conditions and they include using various kinds of stem cells.  Some ethical issues have emerged from the use of stem cells for the treatment of various diseases ranging from research done on stem cells to respect for human life in the treatment of various conditions.  There have also been concerns about the risks versus benefits of using this therapy, but the studies on the risks have not yet fully been explored in the medical field.  Some arguments have been put across to counter the notion that the use of stem cell therapies amount to lack of respect for human life.

Discussion

While there have been many reports in the media  concerning the potential  found in stem cell therapy ,  a large part of medical research and studies is still in earliest stages that involve animal studies and basic laboratory tests.  For this therapy to be used in treatment of any disease,   it has to be tested first in animals and then on humans so that it can be shown to be effective and safe before being availed to patients.  This therapy involves a process called differentiation where stem cells are turned into specific cells and then transplanting them into patients with an aim of treating different injuries and diseases, and this is considered to be part of regenerative medicine.  This intervention usually has a goal of using these stem cells in replacing tissues that were damaged from a disease or an injury although the obstacles to successful use of the method.  Such obstacles include the patient’s body rejecting the transplanted cells and the requirement that patients have to take some drugs that will suppress the immune system (Trounson, & Courtney, 11). On that note, scientists bet on induced pluripotent stem cells which can be created from the actual patient’s cells and as such the body may not reject them after transportation.  The only stem cells types that may differentiate (are pluripotent) are embryonic stem cells and these are developed into partly differentiated stem cells which may result to various different cell lines but they cannot become any cell type any longer (are multipotent (Trounson, & Courtney, 12). Stem cells from adults are multipotent cells present restricted differentiation ability and normally develop into specific tissue, organ or organ system cells.  The harvesting of adult stem cells can be done from the adipose tissue, bone marrow and blood from umbilical cord.   It is worth noting that ethical concerns surrounding research on stem cells are not related to adult stem cells but majorly on embryonic stem cells (Lanza and Anthony, 647).

 It has been expected that the use of stem cell therapy will be beneficial in curing a wide range of ailments and conditioned that patients are suffering from.  The benefits of bone marrow transplant have particularly been expected to benefit those patients needing hematopoietic and immune systems’ reconstruction, using stem cell transplantation using other types of cells.  Optimism has been especially high for pluripotent stem cells and also induced pluripotent stem cells for various applications.  The research on the use of cell therapy has been sponsored through public funding through academic institutions and private sector companies, and the combination of the two has received great advocate (Trounson, & Courtney, 17).  This support has focused on trials in clinical stem cells and translation for sustainable capacity.  Such funding is very important considering that success in new therapies involves a significant cost which may not be sustained easily in absence of guidance and evaluation. Cell therapies prevalence for diseases and injuries  in major organs such as  the eye has a notable trend , and such progress can be attributed to few factors which includes smaller number of cells being required , accessibility  of easy surgery and uncomplicated visualization and assessment  of related grafts(Trounson, & Courtney, 17).  In addition, the eye’s allogeneic transplants appears to have some  immune privilege and the fact that it is possible to use one eye as a control upon the application of cell therapy to the other eye since disease is mostly bilateral.  Differentiating pluripotent cells into the type of cells required for regenerative function is also easy and therefore, many cells types have been put into use while carrying out clinical trials for eye injury and disease. Such successes represent exciting prospects for various stem cell therapies arising from previous trials in addition to some disappointments that are killing the optimism for other cures being successful across a wide range of injuries and diseases (Trounson, & Courtney, 22).

Therapies of Induced pluripotent stem cells and embryonic stem cells have become popular in clinical trials due therapeutic potential expectation especially where it is difficult to access, derive and expand adult stem cells that are functional.  The  various diseases in which this therapy can be used seems to be the pancreas, the eye and some degenerative injuries or disorders injury on spinal cord and Parkinson’s disease , and are possible candidates for cell therapy based on pluripotent stem cells. Cancer treatment has also been the focus of scientist using the same therapy. Therapy on transplant of Limbal stem cells has been used in restoring corneal epithelium which is transparent and is capable of self-renewing in patients suffering from corneal destruction as a result of burns (Nikolic, Boris, et al, 999). Neural stem cell therapy is in the stage of clinical trial and the primary aim of its application is to repair central nervous system that has been damaged. However, the best neural cell type for use in this regenerative repair has not yet been determined and may differ in accordance to the injury and the disease.   Therapies using progenitor and placental stem cells are being studied currently for various diseases .A portion of placental mesenchymal stem cells has been applied in the treatment of patients suffering from idiopathic pulmonary fibrosis (Nikolic, Boris, et al, 1003).  Cell therapies that use Mesenchymal stem cells are being studied in various clinical trials, while such cells play an important role in suppressing proliferation of activated T cell and related cytokine production. This therapy also expected to have a large contribution in the repairing of cartilage and bones and in the union of bone fracture; it has shown to reduce the time needed.

There have been concerns of failures in the use of stem cell therapy, relating to multi-potentiality and pluri-potentiality for some cells of different origins like the small vascular system cells, cells from amniotic fluid and umbilical cord blood. They have not converted to initially anticipate wide utilization, in treatment and prevention of diseases.  There have been inconsistencies on collected clinical data on the benefits of treating diseases such as ischemic disease of the heart. There have also been frequent failures on therapies using mesenchymal stem cells and in most recent cases, trials for treating ulcerative colitis, cardiac repair and ischemic stroke (Nikolic, Boris, et al, 1007).  While it is possible that the failures could have resulted from using dead cells due to the methods applied, it shows that there is danger in transplanting stem cells that are undifferentiated leading to formation of complications in the patients targeted.  However, the progress made on the use of stem cell therapy in clinical trials raises the optimism of future success, since most of these trials are in second stage and there is accumulation related clinical data.  It is too early to conclude that the stem cells utilization in therapy will deliver on their promise. Some trials have not yet obtained approval to be used in the human studies, though there has been one patient who was successfully treated for a condition of muscular degeneration (Nikolic, Boris, et al, 1007). The lack of such approval can be attributed to lack of sufficient documented scientific data that can show strong benefit for the use of stem cell therapy.  The previous efficacy studies have not shown enough clinical benefit to warrant enough regulator support or even a lot of finances; this calls for the need to show clearly that there is considerable clinical benefit especially for studies in phase II (Nikolic, Boris, et al, 1010). This is because of the heterogeneity of diseases affecting humans, which erodes the importance of small benefits clearly observed in the early trials.  The routine use of stem cell therapy in treatment of diseases such as lymphoma and leukemia at times serve to support its use in a myriad of other conditions after successful clinical trials .As a result, the use of this therapy may become a clinical reality in specific areas while in to other areas it is presently a promise and hope.  

 The use of stem cell therapy in the treatment of diseases and injuries has raised a myriad of concerns and ethical issues.  The majority of such issues have mostly emerged from the use of embryonic stem cells in treatment which is based on the necessary clinical research where humans are involved. A common argument holds that this results to lack of respect for precious human life, which requires that the human embryos be respected.  Some individuals believe that the whole process from carrying out studies in clinical settings to the final product for treatment violates the principle of respecting human life. They opposition results from the destruction of an embryo while harvesting the stem cells for the purpose of research and later transplantation in another human’s body (Nuffield Council on Bioethics, 7). Further concern involve the argument that creating embryos to be used in research and  derive stem cells leads to the possibility of human life de-sensitization , and the possibility of uncontrollable instrumentalization and even commercialization of human bodies .    This therapy and related issues are directly connected to the legal and moral status of the related human embryo.

 An important question raised in this debate is whether destruction of one embryo can be justified if it stems cells derived from it can cure many patients suffering from various diseases. Another issue regards the risks associated with the use of stem cell therapy for treatment diseases and injuries.  The issue is complicated by lack of published studies on the same and only preliminary research data is available in relation to the related risks.  For example, in the treatment of cancer, there may be a risk of aggravating further progress of this disease given that the stem cell therapy involves the introduction of foreign stem cells into the affected body part. Even if the stem cell is to be harvested from the patients themselves so that they are not foreign to their body, there is the possibility of aspects like uncontrolled growth still occurring and hence, worsening the condition further (Nuffield Council on Bioethics, 8).  Moreover, where there exist no regulation and thorough supervision, there is a danger of using disallowed stem cells such ones h harvested from the other animals.

Works cited

Lanza, R P, and Anthony Atala. Handbook of Stem Cells: Vol. 1. London: Elsevier/Academic Press, 2013. Print. 646-648

Trounson, Alan, and Courtney McDonald. "Stem cell therapies in clinical trials: progress and challenges." Cell Stem Cell 17.1 (2015): 11-22.

Nikolic, Boris, et al. "Stem cell therapy: a primer for interventionalists and imagers." Journal of Vascular and Interventional Radiology 20.8 (2009): 999-1012.

Nuffield Council on Bioethics. Stem Cell Therapy: The Ethical Issues: a Discussion Paper. Nuffield Council on Bioethics, 2000.7,9