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Embryonic stem cell
open-in-new
<p>Embryonic stem cells (ESCs) are <a href="/facts/Cell_potency/81323LbR">pluripotent</a> <a href="/facts/Stem_cell/qgB9dFrI">stem cells</a> derived from the <a href="/facts/Inner_cell_mass/WSfgAhmH">inner cell mass</a> of a <a href="/facts/Blastocyst/WkRkxdzc">blastocyst</a>, an early-stage pre-<a href="/facts/Implantation_(human_embryo)/k6XJfNMv">implantation</a> <a href="/facts/Embryo/9QHnLVLN">embryo</a>. Human <a href="/facts/Embryo/9QHnLVLN">embryos</a> reach the <a href="/facts/Blastocyst/WkRkxdzc">blastocyst</a> stage 4–5 days post <a href="/facts/Human_fertilization/0E4Pp1qM">fertilization</a>, at which time they consist of 50–150 cells. Isolating the <a href="/facts/Inner_cell_mass/WSfgAhmH">inner cell mass</a> (embryoblast) using <a href="/facts/Immunosurgery/HrBPlQv3">immunosurgery</a> results in destruction of the blastocyst, a process <a href="/facts/Stem_cell_controversy/YVa4gSeu">which raises ethical issues</a>, including whether or not embryos at the pre-implantation stage have the same moral considerations as embryos in the post-implantation stage of development. </p><p>Researchers are currently focusing heavily on the therapeutic potential of embryonic stem cells, with clinical use being the goal for many laboratories. Potential uses include the treatment of <a href="/facts/Diabetes/2xeHXbsI">diabetes</a> and <a href="/facts/Heart_disease/HD420nMv">heart disease</a>. The cells are being studied to be used as clinical therapies, models of <a href="/facts/Genetic_disorders/hFqt2NLn">genetic disorders</a>, and cellular/DNA repair. However, adverse effects in the research and clinical processes such as tumors and unwanted <a href="/facts/Immune_response/dtLulqIy">immune responses</a> have also been reported. </p>