A pathologist's perspective on induced pluripotent stem cells

Abstract

Induced pluripotent stem cell (iPSC) technology was originally developed in 2006. Essentially, it converts somatic cells into pluripotent stem cells by transiently expressing a few transcriptional factors. Once generated, these iPSCs can differentiate into all the cell types of our body, theoretically, which has attracted great attention for clinical research including disease pathobiology studies. Could this technology then become an additional research or diagnostic tool widely available to practicing pathologists? Here we summarize progress in iPSC research toward disease pathobiology studies, its future potential, and remaining problems from a pathologist's perspective. A particular focus will be on introducing the effort to recapitulate disease-related morphological changes through three-dimensional culture of stem cells such as organoid differentiation.

Figure 1

Organoid generation from ESCs/iPSCs and ASCs and their applications. Organoids are generated from ESCs/iPSCs or ASCs. iPSCs can be established from peripheral blood mononuclear cells (PBMCs) or fibroblasts. ASC-based organoids are initiated from organ biopsy samples from normal or tumor tissue, followed by dissociation into epithelia containing stem cells. Both organoids are self-organized via three- dimensional (3D) culture with differentiation and/or expansion medium. They are utilized for disease modeling, drug screening and organoid biobank which can be a unique resource for pathobiology studies.