Question: Adult stem cells are cultivated for what purpose or purposes?
About the article "Stem cell", section "Adult".

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 Veterinary applications of stem cell therapy as a means of tissue regeneration have been largely shaped by research that began with the use of adult-derived mesenchymal stem cells to treat animals with injuries or defects affecting bone, cartilage, ligaments and/or tendons.
There are two main categories of stem cells used for treatments: allogeneic stem cells derived from a genetically different donor within the same species and autologous mesenchymal stem cells, derived from the patient prior to use in various treatments.
A third category, xenogenic stem cells, or stem cells derived from different species, are used primarily for research purposes, especially for human treatments.
Most stem cells intended for regenerative therapy are generally isolated either from the patient's bone marrow or from adipose tissue.
Mesenchymal stem cells can differentiate into the cells that make up bone, cartilage, tendons, and ligaments, as well as muscle, neural and other progenitor tissues, they have been the main type of stem cells studied in the treatment of diseases affecting these tissues.
The number of stem cells transplanted into damaged tissue may alter efficacy of treatment.
Accordingly, stem cells derived from bone marrow aspirates, for instance, are cultured in specialized laboratories for expansion to millions of cells.
Although adipose-derived tissue also requires processing prior to use, the culturing methodology for adipose-derived stem cells is not as extensive as that for bone marrow-derived cells.
While it is thought that bone-marrow derived stem cells are preferred for bone, cartilage, ligament, and tendon repair, others believe that the less challenging collection techniques and the multi-cellular microenvironment already present in adipose-derived stem cell fractions make the latter the preferred source for autologous transplantation.
New sources of mesenchymal stem cells are currently being researched, including stem cells present in the skin and dermis which are of interest because of the ease at which they can be harvested with minimal risk to the animal.
Hematopoetic stem cells have also been discovered to be travelling in the blood stream and possess equal differentiating ability as other mesenchymal stem cells, again with a very non-invasive harvesting technique.
There has been more recent interest in the use of extra embryonic mesenchymal stem cells.
Research is currently underway to examine the differentiating capabilities of stem cells found in the umbilical cord, yolk sac and placenta of different animals.
These stem cells are thought to have more differentiating ability than their adult counterparts, including the ability to more readily form tissues of endodermal and ectodermal origin.  
The stem cell controversy is the ethical debate centered only with research involving the creation, usage, and destruction of human embryos.
Most commonly, this controversy focuses on embryonic stem cells.
Not all stem cell research involves the creation, usage and destruction of human embryos.
For example, adult stem cells, amniotic stem cells and induced pluripotent stem cells do not involve creating, using or destroying human embryos and thus are minimally, if at all, controversial. 
Stem cell research has the potential to cure many diseases, though much skepticism surrounds the issue.
Those opposed to stem cell research concordantly agree on the primary basis that the research is unethical.
Currently, technology allows for the destruction of the human embryo and/or therapeutic cloning of the cells, therefore enabling eyebrows to be raised, although recent research has shown the ability to manipulate adult stem cells into embryonic like cells which can serve with the same purpose.
Both scientists and those opposing stem cell research may soon agree on the use of adult stem cells, rather than embryonic stem cells. 
Adult stem cells are undifferentiated cells, found throughout the body after development, that multiply by cell division to replenish dying cells and regenerate damaged tissues.
Also known as somatic stem cells (from Greek Σωματικóς, meaning "of the body"), they can be found in juvenile as well as adult animals and human bodies.
Scientific interest in adult stem cells is centered on their ability to divide or "self-renew" indefinitely, and generate all the cell types of the organ from which they originate, potentially regenerating the entire organ from a few cells.
Unlike embryonic stem cells, the use of human adult stem cells in research and therapy is not considered to be controversial, as they are derived from adult tissue samples rather than human 5 day old embryos generated by IVF (in vitro fertility) clinics designated for scientific research.
They have mainly been studied in humans and model organisms such as mice and rat. 
 therapies.
The therapeutic potential of adult stem cells is the focus of much scientific research, due to their ability to be harvested from the patient.
In common with embryonic stem cells, adult stem cells have the ability to differentiate into more than one cell type, but unlike the former they are often restricted to certain types or "lineages".
The ability of a differentiated stem cell of one lineage to produce cells of a different lineage is called transdifferentiation.
Some types of adult stem cells are more capable of transdifferentiation than others, but for many there is no evidence that such a transformation is possible.
Consequently, adult stem therapies require a stem cell source of the specific lineage needed, and harvesting and/or culturing them up to the numbers required is a challenge.