In Vivo Pluripotency Assays

MDS offers services for in vivo derivation and characterization of client's hES cell lines by Xenografting of hES cells in SCID mouse (teratoma model) and by expression analysis of markers characteristic for undifferentiated and differentiated hES cells as well as Karyotyping, FISH, Telomerase activity measurement.

• To determine the origin (human, mouse) and tissue type within teratomas, we combine histopathological and extensive marker expression analysis. To evaluate whether the tissues were of human origin we used several human-specific antibodies, e.g.,
  • Anti-E-cadherin
  • Anti-human nuclei
  • or other markers selected by client
• To confirm the presence of tissues derived from all three germ layers, we will focus on tissues that can be easily distinguished by immunohistopathological methods such as:
  • Neuroectoderm precursor (Nestin mAb)
  • Neurons (ß-tubulin-III mAb)
  • Cartilage
  • Kidney tubuli
  • Gut-like epithelium.
• To strengthen these conclusions, we will also use antibodies against markers characteristic for derivatives of the germ layers, e.g.,
  • Alpha -smooth muscle (actin, desmin, nestin, ß-III-tubulin, alpha-fetoprotein, and HNF3ß). Neuroectoderm precursor (Nestin mAb)
  • Neurons (ß-tubulin-III mAb)
  • Endodermal cells (mAb against Cdx2 ; gut endoderm, visceral endoderm, polyclonal antibodies against -1-fetoprotein and HNF3ß)
  • Mesodermal cells (desmin antibody)
  • hES cell-derived cells ( mAbs against human nuclei and human E-cadherin