Other sources of stem cells
The most studied sources of adult stem cells are:
- bone marrow
- peripheral blood
- umbilical cord blood
- adipose tissue
- umbilical cord tissue
- amniotic fluid
- milk teeth pulp
Recently the presence of stem cells was revealed in breasts milk. Also there is data about successful use of the muscular myoblasts (muscular tissue stem cells) in the treatment of ischemic heart disease. Moreover, the update scientific investigations disproved the myth that nervous cells do not restore, as in such evolutionary old parts of human brain as hippocampus, subventricular zones and the zone of the olfactory bulbs the neural stem cells were revealed, capable to give rise both to new neurons and supporting cells of the nervous tissue. But as the obtaining of stem cells from skin, muscular or cardiac tissue, liver or nervous system is accompanied by high traumatism and the methods of their separation are extremely expensive, the following adult stem cells sources found the widest use: bone marrow,peripheral and umbilical cord blood, adipose tissue and placenta. Bone marrow is the rich source of the hematopoietic and mesenchymal stem cells with the biggest experience of practical application in medicine (more than 50 years). Today the bone marrow transplantation in many cases is the only method of treatment of malignant and aplastic blood diseases. But the complications of the search of the matching bone marrow donor and traumatazing procedure of its collection (necessity of the general narcosis, duration about 1.5 h) mediated the wide use of the alternative sources of the hematopoietic stem cells, first of all peripheral and
About peripheral blood stem cells
Peripheral blood of the healthy adult contains small amount of hematopoietic stem cells, which usually is insufficient for the hematopoiesis restoration after chemotherapy/irradiation in the treatment of leukemias. But the developed methods of preliminary stimulation of hematopoiesis, most often due to administration of the granulocyte colony-stimulating growth factor in most cases enable to obtain the quality cell transplant.
Procedure of the collection of the stem cells from the peripheral blood is called apheresis (leuk-/cytapheresis). Cytapheresis implicates the catheterization of the peripheral or central vein of the donor and transmission of their blood through the special device, which enables to catch the hematopoietic stem cells from the blood flow. In many cases the stem cells, necessary for treatment may be obtained from the patients theirselves and autotransplantion is perfomed. This procedure usually lasts several hours and does not require anesthesia.
The use of the peripheral blood hematopoietic stem cells. The first in the world peripheral blood hematopoietic stem cells transplantation was prerfomed by Donnal Thomas. This scientist in turn in 1990 received the Nobel Prize for the improvement of this method for the treatment of leukemias and other life-threatening diseases. Today peripheral blood hematopoietic stem cells transplantation, besides blood cancer treatment, is widely used in regenerative therapy
- coronary heart disease; rheumatoid arthritis;
- systemic sclerosis;
- lupus erythematosis;
- diabetes mellitus and its complications;
- Parkinson’s disease;
- Crohn’s disease
- liver cirhosis;
- Alzheimer’s disease and others.
In December 2012 the European Assocoation on Bone Marrow Transplantation (EBMT) reported about millionth patient, to whom the peripheral blood hematopoietic stem cells transplantation was perfomed.
About the adipose tissue stem cells
Adipose tissue attracts more and more attention of the clinicists as the rich and accessible source of the mesenchymal stem cells. The first attemps to derive stem cells from the adipose tissue belong to the scientists Rodbell and Jones and are dated 1960. Today it was proved that the cells, obtained from so called stromal-vascular fraction of the adipose tissue, are capable to differentiate into the cells of the bone, cartilaginous and muscular tissues, give rise to endoteliocytes (vessel cells) and cardiomyocytes (cells of the heart muscle). Also in adipose tissue a variety of important immunocompetent cells were detected. Adipose tissue is a perspective source of the progenitors-cells, which may be used in the treatment of ischemic diseases of the heart and lower extremities. For example, it is known that 107-109 endothelial progenitor cells are required for the treatment of the ischemic diseases, the amount of which in peripheral blood is very low. The umbilical cord blood is the rich source of the endothelial progenitor cells, but for patients, who do not have the cryoconserved “reserve” of the own umbilical cord blood, collected at birth, the adipose tissue may be the best source. The important features of the adipose tissue stem cells are:
- Capability to transform into the other cells;
- Capability to migration to damaged tissues and organs;
- Engraftment in damaged tissues and organs and their restoration.
The decreased expression of HLA antigens is also an important biological characteristics of the adipose tissue stem cells transplant, and, relevantly, low immunogenecity. This allows, in the case of necessity, to use adipose tissue stem cells in other persons without risk of immunological complications.
Collection of adipose tissue stem cells. Today the most sparing methods of the adipose tissue collection under local anesthesia are developed – miniliposaction substantially from any part of the body. At the same time, the adipose tissue stem cells may be collected also at liposaction aimed at figure correction.
Clinical application of the adipose tissue stem cells. Actually in the world 64 clinical trials are conducted on the evaluation of the regenerative potential of the adipose tissue stem cells for the treatment of:
- Multiple sclerosis
- Crohn’s disease
- Degenerative arthritis
- Lower limbs ischemia
- Burger’s disease
- Coronary heart disease
- Parkinson’s disease.
Also stromal-vascular fraction of the adipose tissue is used in plastic and reconstructive surgery of breasts, for the treatment of recto-vaginal fistulas, in orthopedics and traumatology.