The Types of stem cells: Totipotent Pluripotent Multipotent

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1 Stem Cells is the main material for building and regeneration of the body Stem cells are not differentiated and can transform to any cell of organism Stem cells are capable of indefinite renewal through cell division and retention of their generic or unspecialized state at the same time maintaining their potential to give rise to daughter cells of a more specialized type The Types of stem cells: Totipotent Pluripotent Multipotent

2 Totipotent stem cells are known as the master cells of the body because they have the capacity to differentiate into the 216 specialized cell types that comprise the human body plus the placenta. A fertilized egg is an example of a totipotent cell. Pluripotent stem cells are highly versatile cells and can give rise to any specialized cell type in the body except those needed to develop a fetus. Embryonic stem cells are pluripotent. Multipotent stem cells can give rise to several specialized daughter cells but are limited to the particular tissue, organ or physiological system of origin. For example, hematopoietic stem cells can produce many types of blood cells in the circulatory system but cannot differentiate into a brain cell. Hematopoietic stem cells are an example of adult stem cells and are multipotent. Stem cells from umbilical cord blood are also multipotent based on evidence to date.

3 Sources of Totipotent, Pluripotent and Multipotent Stem Cells Sources of Stem cells Fertilized Eggs Stem cells (totipotent) Embrionic Stem Cells (pluripotent) Fetal Tissue Stem Cells ( pluripotent/multipotent ) Umbilical Blood Stem Cells ( pluripotent/multipotent ) Bone Marrow Mesenchimal SC ( multipotent ) Adult Stem Cells from Different Tissues (multipotent)

4 Embryonic Stem Cells Pluripotent Embryonic Stem Cells Embryonic Germ Cells Embryonic Carcinoma Cells

5 Differentiation of Human Body Cells from Totipotent Stem Cells to Unipotent Tissue Cells

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7 Totipotent stem cells are the master cells of the body because they have the capacity to differentiate into the 216 specialized cell types that comprise the human body plus the placenta. The only totipotent cells are the fertilized egg and the first 4 or so cells produced by its cleavage. In mammals, the expression totipotent stem cells is a misnomer totipotent cells cannot make more of themselves

8 Stem Cells From FertIized Egg Embrionic pluripotent stem cells are derived from the inner cell mass of blastocysts created during artificial in vitro fertilization of human eggs

9 Pluripotent stem cells are highly versatile cells and can give rise to any specialized cell type in the body except those needed to develop a fetus.

10 Embrionic Germ Stem Cells Embrionic Carcinoma Stem Cells Embryonic Germ (EG) Cells are isolated from the precursor to the gonads in aborted fetuses. Embryonic Carcinoma (EC) Stem Cells can be isolated from teratocarcinomas, a tumor that occasionally occurs in a gonad of a fetus.

11 Fetus Stem Cells Fetus Stem Cells are isolated from aborted fetuses. Fetus Stem Cell using has caused ethical problems and debates Aborted fetus material often is contaminated and its using as the source of stem cells rare is safe

12 Cord blood, which traditionally has been discarded, has emerged as an alternative source of hematopoietic stem cells for the treatment of leukemia, lymphoma and other lethal blood disorders. Umbilical cord blood from newborns is a rich source of hematopoietic stem cells.

13 Adult Stem Cells Adult Stem Cells Bone Marrow Stem Cells Neural Stem Cells Skeletal Muscle and Heart Stem Cells Skin Stem Cells Fat Tissue Stem Cells Peripheral Blood Stem Cells Stem Cells of Cornea, Intestines, etc.

14 Adult Multipotent Somatic Stem Cells Adult ( Somatic ) stem cells are unspecialized cells that are found in different parts of the body and, depending on the source tissue have different properties. The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found.

15 Bone Marrow Stem Cells Hematopoietic stem cells that give rise to all blood and immune cells are today the most understood of the adult stem cells. Hematopoietic stem cells from bone marrow have been providing lifesaving cures for leukemia and other blood disorders for over 40 years.

16 Bone Marrow Stem Cells Hematopoietic stem cells are primarily found in the bone marrow but have also been found in the peripheral blood in very low numbers. Compared to adult stem cells from other tissues, hematopoietic stem cells are relatively easy to obtain. Mesenchymal stem cells are also found in the bone marrow Mesenchymal stem cells are a mixed population of cells that can form fat cells, bone, cartilage and ligaments, muscle cells, skin cells and nerve cells.

17 Bone Marrow Stem Cells Adult stem cells are multipotent, meaning that they appear to be limited in the cell types that they can produce. But adult stem cells may have more plasticity than originally thought. Stem cell plasticity is the ability of a stem cell from one tissue to generate the specialized cell type(s) of another tissue. For example, bone marrow stromal cells are known to give rise to bone cells, cartilage cells, fat cells and other types of connective tissue (which is expected), but they may also differentiate into cardiac muscle cells and skeletal muscle cells (this was not initially thought possible).

18 Adult Stem Cells There are a very small number of stem cells in each tissue. Stem cells are thought to reside in a specific area of each tissue where they may remain quiescent (non-dividing) for many years until they are activated by disease or tissue injury. A potential advantage of using stem cells from an adult is that the patient's own cells could be expanded in culture and then reintroduced into the patient. The use of the patient's own adult stem cells would mean that the cells would not be rejected by the immune system.

19 Adult Stem Cells Isolation And Cultivation Large numbers of embryonic stem cells can be relatively easily grown in culture, while adult stem cells are rare in mature tissues and Methods for expanding their numbers in cell Culture is still hard and complicated. This is An important distinction, as large numbers of cells are needed for stem cell replacement therapies.

20 Adult Stem Cell Plasticity Adult stem cell plasticity and transdifferentiation. Certain adult stem cell types are pluripotent. This ability to differentiate into multiple cell types is called plasticity or transdifferentiation. Hematopoietic stem cells may differentiate into: three major types of brain cells ( neurons, oligodendrocytes, and astrocytes); skeletal muscle cells; cardiac muscle cells; and liver cells. Bone marrow stromal cells may differentiate into: cardiac muscle cells and skeletal muscle cells. Brain stem cells may differentiate into: blood cells and skeletal muscle cells.

21 Diseases Treated With Stem Cells Alzheimer's Autism Autoimmune diseases Anemias Bone and cartilage deformities Burns Cancer (brain, breast, ovarian, etc.) Cerebral palsy Corneal scaring Crone's disease Diabetes Heart disease Immunodeficiencies Repair of cardiac tissue after MI Leukemias Lymphomas Melanoma Multiple sclerosis Multiple myelomas Muscular dystrophy Neural blastoma Osteoarthritis Paralysis Parkinson's Disease Rheumatoid arthritis Scleroderma Scleromixadema Spinal chord damage Stroke Systemic lupus Tendonitis

22 Stem Cells In Neurodegenerative Diseases Stem cell therapy is the most promising and effective cure of neurological diseases. In some neurodegenerative diseases stem cell therapy is 8-15 times more effective than standard therapy, in others stem cell therapy is the only treatment and hope for patients

23 Stem Cells In Neurodegenerative Diseases Stem cells of different origin (embryonic, umbilical cord blood, bone marrow, adult stem cells, etc.) can participate in repair of damage after stroke. Stem cells have a great potential in Parkinson disease, rescuing and preventing the degeneration of endogenous dopaminergic neurons. Stem cells provide remyelinization in multiple sclerosis and amyotrophic lateral sclerosis and may be the best choice for treatment of these diseases. Stem cells are very promising for the treatment of Alzheimer s diseases, head trauma, brain tissue injuries of different kind, in other neurological conditions and pathologies.

24 Stem Cells In Neurodegenerative Diseases In neurodegenerative diseases for by-passing blood-brain barrier stem cells may be injected sub thecal into spinal fluid or directly into the brain tissue.

25 Stem Cells In Heart Diseases Stem cells have been identified as Integrating into cardiac tissue, forming cardiomyocytes and / or cardiac blood vessels, regenerating infarcted heart tissue, and improving cardiac function. All kinds of stem cells injected into old animals seems capable of restoring cardiac function, apparently through increased activity for cardiac blood vessel formation.

26 Stem Cells In Heart Diseases The evidence has led numerous groups to use stem cells of different origin in treatment of patients with damaged cardiac tissue. Results from these clinical trials indicate that the stem cells, including cells from the patients themselves, can regenerate damaged cardiac tissue and improve cardiac performance in humans. In terms of restoring angiogenesis and improving blood circulation, results in patients are not limited to the heart. Stem cells from the patients themselves can improve blood circulation in gangrenous limbs, in many cases obviating the need for amputation.

27 Fat Tissue Stem Cells Adipose tissue, also known as fat tissue, is one of the most recently discovered sources of adult stem cells. In addition to stem cells, there lies within adipose tissue a defined population of cell types that are also major contributors to healing, referred to as 'regenerative cells.' Together, these stem and regenerative cells represent tremendous opportunities for treating cardiovascular disease, spine and orthopedic disorders, vascular conditions, reconstructive surgery as well as a variety of other areas of medicine.

28 Fat Is Rich Stem Cell Source Rich Cell Source Adipose tissue is the richest and most accessible known source in the human body of adult stem cells. By comparison, it contains a hundred times more stem cells in the same amount of bone marrow, a commonlyused source for stem cells. Adipose tissue is the richest known source for stem cells

29 Fat Stem Cell Action Adipose tissue contains numerous types of regenerative cells. These include adult stem cells, vascular endothelial cells, vascular smooth muscle cells and other cell types. These cells collectively contribute to healing and repair through a variety of mechanisms that involve promoting blood vessel growth in an area of injury, keeping alive injured cells that are at risk of dying (antiapoptosis), and the ability to differentiate into several tissue types, such as bone, cartilage, fat, skeletal muscle, smooth muscle and cardiac muscle.

30 Fat Stem Cells Separation And Cultivation There are lots of different separation techniques for isolation of fat stem cells: Acoustophoresis, Dielectrophoresis, Density Gradient Centrifugation, etc. There are also many techniques and protocols for fat stem cell cultivation in media.

32 American Armenian Health Development Center Collaboration between Armenia and USA in the field of Stem Cell therapy Address: Andranik 3 Yerevan, Armenia