Clinical uses of mesenchymal stem cells – Wikipedia, the free …

Adult mesenchymal stem cells (MSCs) are being used by researchers in the fields of regenerative medicine and tissue engineering, to artificially reconstruct human tissue which has been previously damaged. Mesenchymal stem cells have the capacity to become any type of fully developed cell, which can contribute to replacing muscle tissues or internal organs. To help discover the therapeutic uses of these stem cells they are grown in laboratories or by using medication to stimulate new cell growth within the human body.[1][2][3] In MSC therapy the cells are extracted from the adult patients bone marrow via a procedure called bone marrow aspiration. This usually involves inserting a needle into the back of the patients hip bone and removing the sample from there. These cells are then grown under controlled in vitro conditions in a lab, so that they can multiply and same time mature( also referred to as differentiated. This process may take two to three weeks.[1] The kind of mature, fully differentiated cell phenotype and the number of those cells created though this can be influenced in three ways. Firstly by varying the initial seed density in the culture medium, secondly through changing the conditions of the medium during expansion, and lastly through the addition of additives such as proteins or growth hormones to the culture medium.[4] They are then harvested and put back into the patient through local delivery or systemic infusion.[1][2][4]

MSCs possess many properties that are ideal for the treatment of inflammatory and degenerative diseases.[2][3] They can differentiate into many cell types including bone, fat, and muscle which allow them to treat a large range of disorders.[1][4] They possess natural abilities to detect changes in their environment, such as inflammation. They can then induce the release of bioactive agents and the formation of progenitor cells in response to these changes.[4] MSCs have also been shown to travel to sites of inflammation far from the injection site.[3][5][6]

MSCs can be easily extracted through well-established procedures such as bone marrow aspiration.[3] Also, transplanted MSCs do not pose any potential for rejection by the patient as they are derived from the patients own tissue.[2]

Several different forms of stem cells have been identified and studied in the field of regenerative medicine. One of the most extensively studied stem cell types are embryonic stem cells (ESCs). ESCs possess many of the same therapeutic properties as MSCs, including the ability to self-regenerate and differentiate into a number of cell lineages.[1] Their therapeutic abilities have been demonstrated in a number of studies of autoimmunity and neurodegeneration in animal models.[1][3][5][7]

However, their therapeutic potential has been largely limited by several key factors.[3] Injected ESCs have been shown to increase the risk for tumor formation in the host patient.[1][3][7] Also, the hosts immune system may reject injected ESCs and thus eliminate their therapeutic effects1.[3] Finally, research has been largely limited due to the ethical issues that surround their controversial procurement from fertilized embryos.[1][7]

MSCs have been used to treat a variety of disorders including cardiovascular diseases, spinal cord injury, bone and cartilage repair, and autoimmune diseases.[4]

A vast amount research has been conducted in recent years for the use of MSCs to treat multiple sclerosis (MS).[8][9] This form of treatment for the disease has been tested in many studies of experimental allergic encephalomyelitis, the animal model of MS, and several published and on-going phase I and phase II human trials.[1][2][4][7]

Current treatments are unable to prevent the accumulation of irreversible damage to the central nervous system (CNS).[6] MS patients experience two major forms of damage, damage resulting from on-going autoimmune induced processes and damage to natural pair mechanisms.[2] Therefore, an ideal treatment must possess both immunomodulating properties to control irregular autoimmune responses to prevent further damage and regenerative properties to stimulate natural repair mechanisms and replace damaged cells.[1][2]

The exact therapeutic mechanisms of MSCs in the treatment of MS are still very much up to debate among stem cell researchers.[1][2][4] Some of the suggested mechanisms are immunomodulation, neuroprotection, and neuroregeneration.[2]

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Clinical uses of mesenchymal stem cells - Wikipedia, the free ...