Stem Cells are cells that have not yet decided what they want to be. Stem cells therefore can be any other cell of the body. The body was developed from embryonic stem cells and is maintained and repaired by adult stem cells. Adult stem cells are located in all tissues of the body and are kept in a resting state until called upon for tissue repair.
Stem Cell Videos
Panzer received stem cell therapy for hip dysplasia and elbow dysplasia (Fragmented Coronoid Processes, or FCP) on May 7, 2015. Panzer is a 13-year-old Rottweiler.
Although IVDD affects all breeds of dogs, as many as 1 in 5 miniature Dachshunds will suffer from the pain and impairment of disk compression. At 6 years old, Scout became acutely paralyzed. Watch his journey to healing with regenerative stem cell therapy.
When stem cells are transplanted into a new location in the body they can change, adapt and modify their function based on the environmental conditions that they find themselves in. The stem cells are like workers that receive their instructions in the form of chemicals in the local environment. They use the raw materials and structure like a carpenter uses lumber and blueprints to rebuild what is missing, damaged or poorly functional. The stem cells’ DNA is modified by the chemicals surrounding the cells causing each cellular division to more closely approximate the original cell and tissue structure. Therefore, a daughter stem cell may differ in cell type from its parent. For example, a stem cell from fat will form new cartilage cells when placed into a joint that has arthritis.
As well as making new cells, stem cells also pump out chemical instructions that regulate and instruct other cells how to participate in the healing regenerative process. Stem cells modulate the inflammation present in a damaged tissue so as to reduce its harmful effects. Stem cells can also resuscitate dying cells by donating missing elements of life from the stem cells’ cytoplasm to an injured cells’ cytoplasm.
If we want to grow replacement organs in the laboratory we need to understand the structure of the tissues. Stem cells live in a body that has three-dimensional structure. Each organ has a structural framework and specific cells attached to it. This 3D structure and the cells and scaffolds that hold it speak a tactile language to the stem cell communicating the needs of the tissue. This communication plus the chemical and cellular communication all happening at a microscopic level determines the ultimate fate of these cells. For example, a lung from a pig can be digested free of cells leaving only the structural collagen “skeleton”. Then stem cells from a human can be applied to this three-dimensional structure and will grow to form a complete functional human lung that can be transplanted into that human with an identical genetic match and without tissue rejection that is commonly seen with donor supplied transplanted lungs.
There are three basic groups of stem cells, embryonic stem cells (ESC), induced pluripotent stem cells (iPSC) and adult stem cells. Embryonic stem cells are found in the placenta and embryos. Induced pluripotent stem cells are genetically modified fibroblasts that have similar properties to embryonic stem cells. Adult stem cells are present in blood, bone marrow and many tissues of the body. In recent years researchers have found that fat tissue has a rich supply of adult stem cells.
While embryonic stem cells have more potential for development into different tissues than adult stem cells they are less predictable and less hardy than the adult stem cells. Embryonic stem cells come from fertilized eggs and must be grown in tissue culture. This is a difficult process requiring strict infection control and strict environmental manipulation. Any stress on these cells causes them to change, to adapt to try to survive by differentiating themselves thereby creating a challenge in the control of the outcome with these cells. Controlled differentiation is possible through the manipulation of the nutrients and chemicals present in their culture so that different cell types can be created. These may be muscle cells, nerve cells or bone cells and so on. Cells that produce insulin have been created in the laboratory from embryonic stem cells. Large numbers of these cells would be necessary for therapy however and growing large numbers is problematic and the longer they grow in culture the less tolerant of normal body conditions they become. Embryonic stem cells have been studied for over three decades with many researchers spending their lives trying to unravel the complexities of the control and characterization of these remarkable cells. Another disadvatage of embyonic cells is that unless our parents had the forsight to have some placental cells stored when we were born we would need to rely on donated cells for treatment.
Induced pluripotent stem cells (iPSCs) can be grown from fibroblasts which are found in skin. Induced pluripotent stem cells are adult cells that have been genetically reprogrammed to an embryonic stem cell–like state by being forced to express genes and factors important for maintaining the defining properties of embryonic stem cells. Although these cells meet the defining criteria for pluripotent stem cells, it is not known if iPSCs and embryonic stem cells differ in clinically significant ways. Mouse iPSCs were first reported in 2006, and human iPSCs were first reported in late 2007. I have had the privilege of spending time training in the creation and cultivation of these cells in the laboratory learning techniques for culturing and characterizing human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), as well as reprogramming techniques for the creation of iPSCs. Although there is huge potential for programming these cells there is much research still to be done before we can grow our own replacement body parts from spare skin.
Adult stem cells were first found in the blood and bone marrow. They were found in small numbers and had to be cultured and expanded to larger numbers to be available for research and therapeutics. These cells have been used in the treatment of leukemia since the 1960’s. Radiation is used to remove all cells in the bone marrow including the cancer cells. Then the bone marrow is repopulated with stem cells called hematopoietic stem cells. These stem cells grow all the different constituents of the blood producing cells located in the bone marrow. Adult stem cells have recently been found in other tissues of the body. In fact, most if not all tissues of the body have adult stem cells. These stem cells are for the restoration, repair and regeneration of damaged tissue. In most tissues, such as the brain spinal cord and heart, these cells are few and far between but in some tissues such as fatty (adipose) tissues these cells are present in huge numbers. These adult stem cells are called mesenchymal stem cells and are the hottest topic in regenerative medicine today. Adipose derived stem cells (ADSCs) for the first time offer a therapeutic option yielding enough cells that are robust and ready to heal to make it clinically viable.
Adipose derived stem cells (ADSCs) are collected by harvesting a small amount of fatty tissue from the belly of the pet. This fat is then gently chemically digested and centrifuged to separate the cells from the stroma and vessels. This mixture of stem cells (ADSCs) and highly active chemical mediators of regeneration and healing is called the stromal vascular fraction (SVF). The administration of the stromal vascular fraction into damaged areas such as joints with arthritis, failing kidneys, failing hearts, damaged spinal cords and so on leads to rapid reduction in inflammation, restructuring and rebuilding of tissue and return to function. This is accomplished within a couple of hours of the pet arriving at the hospital for therapy.
Previously adult stem cells were collected by a bone marrow biopsy. Then the cells were cultured and the culture expanded. The process of culturing and growing enough cells to be effective could take three to six weeks. As well as this time delay the bone marrow derived cells had now been grown in culture and are less hardy and may have lost some of their ability to heal. We can harvest enough adipose derived stem cells from our pet’s own fat that there is no need to culture the cells, therapy can be done within a few hours of removing the fatty tissue.