Question: How are stem cells primarily identified?
About the article "Stem cell", section "Identification".

Candidate passages:
The public in the United States has a general awareness of embryonic stem cells because of the stem cell controversy.
However, cord blood stem cells (hematopoietic stem cells) are not embryonic stem cells (pluripotent stem cells). 
Stem cell markers are genes and their protein products used by scientists to isolate and identify stem cells.
Stem cells can also be identified by functional assays.
Below is a list of genes/protein products that can be used to identify various types of stem cells, or functional assays that do the same.
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It is currently possible to collect two types of stem cells during childbirth: amniotic stem cells or umbilical cord blood stem cells.
To collect amniotic stem cells, it is necessary to do amniocentesis before or during the birth.
Amniotic fluid contains mesenchymal stem cells while umbilical cord blood contains both hematopoietic and mesenchymal stem cells.
Although there are many potential future applications of such stem cells, there are few current therapeutic applications of such stem cells. 
The NYSCF Laboratory is developing The NYSCF Global Stem Cell Array (Array), which, for the first time, manufactures standardized cells that act as human disease models.
Specifically, the Array captures the full spectrum of genetic and ethnic diversity within the human population as stem cell lines.
Both healthy donors and diseased patients contribute skin and/or blood.
Automated robotic technologies and proprietary protocols transform these samples into standardized, high-quality stem cell lines (i.e.
induced pluripotent stem cells or iPSCs), which may thereafter be reprogrammed into other cell types (e.g.
heart cells, liver cells, and brain cells).
These cells provide a platform by which researchers can study basic biological development and disease progression.
Researchers may anticipate, on a large scale, how people from genetically diverse backgrounds respond to new drugs—in other words, conduct “clinical trials in a dish.” For the first time, potential drug metabolism and toxicity issues are identified in advance of human clinical trials.
Additionally, the Array facilitates the customization of drugs and the creation of cell therapies to match a person’s own genetic type, increasing the likelihood of drug success and decreasing the odds of adverse effects. 
Muse cells are identified as cells which are positive for SSEA-3+, a well known marker for undifferentiated human ES cells.
They are also positive for general mesenchymal stem cell markers such as CD105, CD90 and CD29, so that Muse cells are double positive for pluripotent and mesenchymal stem cell markers.
Cell isolation by SSEA-3 cell sorting can be done using SSEA-3 antibody.
Muse cells do not express CD34 (hematopoietic and adipose stem cell markers) and CD117 (hematopoietic stem cells markers), Snai1 and Slug (skin-derived precursors markers), CD271 and Sox10 (neural crest-derived stem cells markers), NG2 and CD146 (perivascular cells) or CD31 and von Willebrand factor (endothelial progenitor markers).
This indicates that Muse cells do not belong to previously investigated stem cell types.