UNASSIGNED: A @entity44 is a @entity5 containing a mixture of differentiated tissues and organotypic derivatives of the three germ layers, while a @entity14641 also contains @entity189 cells (EC cells). Experimental @entity44 and @entity14641 have been derived from early @entity1 embryos transplanted into the adult animal (ectopic sites). In the @entity35 , the pluripotency of the transplanted epiblast was demonstrated and a quantifiable restriction of developmental potential persisted after subsequent transplantation of chemically defined cultivated postimplantation embryos. The @entity35 is nonpermissive for @entity14641 development and @entity35 pluripotent cell lines have been established only recently. Transplantation of @entity19 embryos, epiblast, or embryonic stem cells (mESCs) gave rise to @entity14641 . The pluripotency of reprogrammed @entity1 cells has been tested by a 'gold standard' trilaminar @entity44 assay in immunocompromised @entity19 in vivo. @entity1 pluripotent stem cells proposed for use in regenerative medicine such as @entity1 embryonic stem cell (hESC), @entity1 nuclear-transfer/therapeutic cloning embryonic stem cell (NT-ESC), or @entity1 induced pluripotent stem cell (hiPSC) lines, once differentiated in vitro to the desired cell type, should be again tested in a long-term animal @entity44 assay to exclude their @entity5 . Such an approach led to a recently implemented @entity1 therapy with retinal pigmented epithelium. For greater biosafety, the @entity44 assay should be standardized and complemented by assessments of mutations/epimutations, RNA/protein expression, and possible immunogenicity of autologous pluripotent cells. Furthermore, the standardized @entity44 assay should be directed more to the assessment of EC/malignant cell features than of differentiated tissues, especially after a unique case of @entity1 therapy with neural stem cells was found to lead to @entity5 . WIREs Dev Biol 2016, 5:186-209. doi: 10.1002/wdev.219 For further resources related to this article, please visit the WIREs website.

@entity44 : from spontaneous XXXX to the pluripotency/ @entity5 assay.

@entity1 :: ('9606', 'Species') :: ['mammalian', 'human', 'Human'] @entity14641 :: ('MESH:D018243', 'Disease') :: ['teratocarcinomas', 'teratocarcinoma'] @entity5 :: ('MESH:D009369', 'Disease') :: ['benign tumor', 'malignancy'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity189 :: ('MESH:D002277', 'Disease') :: ['embryonal carcinoma'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity44 :: ('MESH:D013724', 'Disease') :: ['teratoma', 'teratomas']
@entity5 :: (MESH:D009369,Disease) :: ['tumors']
