What Is A Stem Cell bank
A cell bank in its simplest form is a collection of containers of cryopreserved cells that are intgral part of a homogenous cell suspension derived from a single culture of cells.Cells are stored at ultra-low temperature and in this state the cells remain viable indefinitely. On thawing they are able to divide again.
A cryopreserved bank of cells is a kind of freezed culture. The cells can be characterised, qualified
and shared. Read more
How Are Embryonic Stem Cells Grown In Labortary?
Embryonic stem cells,are derived from embryos that develop from eggs that have been fertilized in vitro—in an in vitro fertilization clinic—and then donated for research purposes with informed consent of the donors.
The embryos from which human embryonic stem cells are derived are typically four or five days old and are a hollow microscopic ball of cells called the blastocyst.
The blastocyst is formed by
- Trophoblast, which is the layer of cells that surrounds the blastocyst
- Blastocoel, which is the hollow cavity inside the blastocyst
- Inner cell mass, which is a group of approximately 30 cells.
What Are Adult Stem Cells and Where Are They Found?
An adult stem cell is an undifferentiated cell found among differentiated cells in a tissue or organ. These cells can renew themselves and can differentiate to yield the major specialized cell types of the tissue or organ.
The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found.
They are also termed as somatic stem cell. The origin of adult stem cells in mature tissues is unknown.
Adult stem cells have been found in many more tissues than they once thought possible. In right environment, certain kinds of adult stem cells seem to have the ability to differentiate into a number of different cell types, given the right conditions. If this is possible under lab conditions, these cells may become the basis of therapies for many serious common diseases.
About 40 years ago, researchers discovered that the bone marrow contains at least two kinds of stem cells. One population, called hematopoietic stem cells, forms all the types of blood cells in the body. A second population, called bone marrow stromal cells, generate bone, cartilage, fat, and fibrous connective tissue.
There are a very small number of stem cells in each tissue.They may remain non-dividing for many years until they are activated by disease or tissue injury.
The adult tissues reported to contain stem cells include brain, bone marrow, peripheral blood, blood vessels, skeletal muscle, skin and liver.
Struggle, however is to grow adult stem cells in cell culture and manipulate them to generate specific cell types so they can be used to treat injury or disease.
How To Identify Adult Stem Cells?
One or more of the following three methods are used to identify adult stem cells
- Labeling the cells in a living tissue with molecular markers and then determining the specialized cell types they generate
- Removing the cells from a living animal, labeling them in cell culture, and transplanting them back into another animal to determine whether the cells repopulate their tissue of origin
- Isolating the cells, growing them in cell culture, and manipulating them, often by adding growth factors or introducing new genes, to determine what differentiated cells types they can become.
Brain Tissue Created From Stem Cells
Japanese researchers claim to have created functioning human brain tissue from stem cells, a world first that has raised new hopes for the treatment of disease.
Stem cells taken from human embryos have been used to form tissues of the cerebral cortex, according to experts at the government backed research institute Riken. The tissues self-organised into four distinct zones very similar to the structure seen in human fetuses, and conducted neuro-activity such as transmitting electrical signals.
“Transplanting tissues could raise hopes for greater functional recovery,” the institute said.
But study of invitro cultivation of more mature cortex tissue, such as those with six zones like in the adult human brain, will be stepped up. The tissues could also serve as “a mini organ” for studying the causes of Alzheimer’s disease.
Embryonic stem cells are harvested by destroying a viable embryo, a process that some find unacceptable. Riken said cortex tissues were also obtained from “induced pluripotent stem cells,” which are similar to embryonic stem cells but artificially induced.
How Do Stem Cells Develop and Work?
I can across a very good video that explains basics of stem cells and their functioning very well. This video is about eight minutes long and carries a good explanation about stem cells. Here we go–
What Are Stem Cells?
Stem cells are special types of cells which have the characteristic ability to renew themselves through mitotic cell division [ A kind of cell division in which two similar cells are produced from one cell] and differentiating into a diverse range of specialized cell types.
Stem cells are present in most multi-cellular organisms.
The two broad types of mammalian stem cells are
- Embryonic stem cells
These cells are isolated from the inner cell mass of blastocysts in embryo.In a developing embryo, stem cells can differentiate into all of the specialized embryonic tissues. - Adult stem cells
These are found in adult tissues and participate in repair system for the body, replenish specialized cells and maintain the normal turnover of regenerative organs, such as blood, skin or intestinal tissues.
Stem cells can now be grown and transformed into specialized cells with characteristics consistent with cells of various tissues such as muscles or nerves through cell culture.
Highly plastic adult stem cells from a variety of sources, including umbilical cord blood and bone marrow, are routinely used in medical therapies. Embryonic cell lines and autologous embryonic stem cells generated through therapeutic cloning are promising candidates for future therapies.
Hi
I am Dr Arun Pal Singh. You might know me from boneandspine.com. I would be writing on issues related to stemcells in this blog.
I needed a separate place to write on this topic as this topic is itself quite vast with all kind of possible ramifications.
Research in stem cells is quite promising and still evolving.
Be with me as I search and write.
If you are interested in this topic, you might like to visit this blog again and again. I would suggest you to bookmark the blog.