The Science Behind Regenerative Medicine
About Regenerative Medicine
Regenerative medicine is a new, exciting approach to treating degenerative diseases and injuries that utilizes specially-grown tissues and cells (mostly various stem cells), synthesized compounds, and artificial organs. Targeted and combined applications of these approaches amplify the natural healing ability of the human body in the places it’s needed most and is even capable of replacing the function of a permanently damaged organ or tissue.
The goals of regenerative therapies are to reduce, relieve, and manage specific painful, chronic diseases and dysfunctional conditions, with the purpose of improving function and increasing the patient’s overall quality of life through minimally invasive regenerative procedures. Regenerative medicine shifts the paradigm of treatment to a focus on healing, rather than a focus on pain and disease. By utilizing biomedical stem cell building blocks and growth factors, science can bolster and accelerate the body’s natural healing processes.
About MSCs, from The Institute of Stem Cell Therapy:
What Are Mesenchymal Stromal Cells (MSCs)?
Mesenchymal stromal cells (MSCs) are “multipotent” cells, meaning that they can produce many, but limited types of cells. They are derived from multiple organs and tissues, some of which include bone marrow, umbilical cords, Wharton’s jelly, dental pulp, and peripheral muscle (read more about where MSCs come from here). MSCs are progenitor cells with multiple sources, initially from bone marrow as fibroblastoid colony forming units, and most recently as what’s known as multipotent mesenchymal stromal cells.Mesenchymal stromal cells (MSCs) are “multipotent” cells, meaning that they can produce many, but limited types of cells. They are derived from multiple organs and tissues, some of which include bone marrow, umbilical cords, Wharton’s jelly, dental pulp, and peripheral muscle (read more about where MSCs come from here). MSCs are progenitor cells with multiple sources, initially from bone marrow as fibroblastoid colony forming units, and most recently as what’s known as multipotent mesenchymal stromal cells.
Recent clinical and preclinical studies show that MSCs can play a role in tissue repair and regeneration, and have some remarkable immunosuppressive properties as well. This discovery has led to breakthroughs in many cardiovascular, central nervous, gastrointestinal, renal, orthopedic, and hematopoietic treatment applications.
Another essential property of MSCs is that matching tissue between the MSC donor and recipient doesn’t appear to be necessary. This means that MSCs have the potential to be the first cell type used as an off-of-the-shelf therapeutic product, which is groundbreaking in nearly all treatment applications of MSCs.
What Are Mesenchymal Stromal Cells Used For?
MSCs are increasingly being used to treat a wide variety of disorders including diseases of the musculoskeletal system, aiding wound healing, and vascular disorders. MSCs possess the unique ability to differentiate into several types of cells such as cartilage, bone, and fat. Recent clinical and preclinical studies show that MSCs can play a role in tissue repair and regeneration, and have some remarkable immunosuppressive properties as well. This discovery has led to breakthroughs in many cardiovascular, central nervous, gastrointestinal, renal, orthopedic, and hematopoietic treatment applications. The therapeutic use of MSCs is the foundation for the recent emergence of new self cell-repair technology.
Are Some MSCs More “Potent” Than Others?
The efficiency with which MSCs form colonies is an important factor in determining the overall quality of cells. This essentially means that some cells are “more potent” than others and have higher cell function — or they have a higher capacity to multiply and produce new, healthy cells. Because of this, there have been multiple tests devised to measure both the viability and potency of cells in a specified unit. The most commonly used test that measures the ability of the cells to grow and form colonies in a cell culture is called the colony-forming unit (CFU) assay. The most significant advantage to the CFU assay is that it is able to measure cell function in addition to the number of viable cells. And in fact, most studies show that the number of CFUs in a cell progenitor unit is the single best indicator of viability and potency.
The Future of Regenerative Medicine
The overall aim is to bring advanced solutions that aid and supplement the natural healing mechanisms of the body. One such solution is recapitulating tissue and organ structures by the decellularization and recellularization of organs before transplantation.
Decellularization of organs involves several processes to remove immunogenic cells and molecules from the organ, sparing the framework substance of the tissue, or the extracellular matrix. Decellularized tissue (without recellularization) has been used to repair large tissue damage. A variation of the method is in use for kidney dialysis where blood vessels are processed and decellularized before placing them in patients. While excellent progress has been made in regenerative medicine through decellularization, it is necessary that protocols be further developed to optimize the process.
Another approach in development is altering the host environment and immune system to promote tissue repair. This involves the administration of specific cells, which can indirectly trigger natural therapeutic responses, such as growth factors, without injecting the cells directly into the damaged tissue. One particularly impressive example is injecting cord blood stem cells into a patient with acute stroke to promote migration of neuroblasts to the injury site for the repair and regeneration of brain tissue.
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