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To verify that human induced pluripotent stem cells are indeed pluripotent, there are several available methods. Each have their advantages and disadvantages. For example, the teratoma assay can provide information about the trilineage differentiation potential of human iPS cell lines in a single experiment, but has the disadvantage of being expensive (due to animal housing costs), laborious and requiring a trained pathologist to identify the different lineages within the heterogenous tumor. An alternative means of proving trilineage differentiation potential is to directly differentiate new iPS cell lines to each of the three germ layers in vitro, using specialized media for endoderm, mesoderm and ectoderm germ layer specification. Using defined and reproducible cell culture media provides a robust and consistent method of assessing differentiation potential and these protocols can be scaled down to smaller well formats to increase throughput. STEMCELL offers our our STEMdiff™ line of differentiation products, which include media to generate definitive endoderm (STEMdiff™ Definitive Endoderm Kit), early mesoderm (STEMdiff™ Mesoderm Induction Medium) or neural progenitor cells (STEMdiff™ Neural Induction Medium). Using these three products creates a robust tool for the assessment of trilineage differentiation potential in newly-derived human iPS cell lines.