stem cells


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stem cells

Pluripotential progenitor cells from which a whole class of cells differentiate. A stem cell in the bone marrow, for instance, gives rise to the entire range of immune system blood cells (neutrophils, eosinophils, basophils, monocytes/macrophages, platelets, T cells and B cells) and the red blood cells (erythrocytes). Stem cells from embryos or umbilical cord blood have a considerable potential for medical treatment. Implanted stem cells are capable of converting to definitive tissue cells because they contain the complete genome and appropriate parts of this will be switched on in response to the new environment. Isolated adult mesenchymal stem cells have been shown to change appropriately in response to the physical density or toughness of that environment and become nerve tissue, fat, ligament, tendon, muscle, cartilage or bone. To be effective, stem cell therapy must take account of this fact.

Stem cells

Parent cells from which other cells are made.
Mentioned in: Amyloidosis
References in periodicals archive ?
The human cell lines were generated using ReNeuron's patented c-mycERTAM stem cell expansion technology, and were pre-screened for both genetic stability and their ability to differentiate into tyrosine hydroxylase (TH)-expressing neurons.
This work, Boyer predicts, will provide more insights both about pluripotency in stem cells and about the remarkable process by which a single fertilized cell becomes an entire organism.
Moreover, destroying an embryo for stem cells may not seem as grotesquely immoral as carving up an adult for parts, but the principle of expediency at work in both situations is still the same.
The mammary tumor stem cells represented only 2 percent of the unfractionated bulk tumor cells.
Although embryonic stem cells, or ES cells, hold the greatest potential for medical research, they also awaken the greatest fears about the direction of medical research.
Pluripotential stem cells can also differentiate into various kinds of specialized cells when they are appropriately stimulated.
And adult stem cells could be the solution to everyone's moral, religious and ethical issues.
Right now, all stem cell lines used to treat diseases have come from embryonic stem cells or adult stem cells donated by healthy people.
Upon closer inspection, the number of viable stem cell lines turns out to be fewer than a dozen.
According to the National Institutes of Health, stem cells from embryos, so-called "pluripotent" cells, are more flexible than adult stem cells and can thus be manipulated into more types of body tissues, including bone, skin, and muscle.
Before embryonic stem cells can be used for research, they must be used to create a continuously growing "line" of master cells, a difficult laboratory process that works only a small percentage of the time.
Stem cells from this embryo could be cloned and used to grow replacement liver tissue with matching DNA.