Are you confused about all the different types of stem cells? Read on to learn where different types of stem cells come from and what their potential is for use in therapy.
Stem cells (SCs) are defined as cells that show self-renewal either with or without differentiation, depending on the symmetry of the division. After fertilization of the oocyte, symmetric cell divisions (SD) followed by asymmetric cell divisions (AD) form a blastocyst. The inner cell mass (ICM) contains pluripotent embryonic stem cells (ESCs) which are able to differentiate into every cell type of the three germ layers (endoderm, mesoderm, and ectoderm) of the embryo (Figure). After the gastrulation process, the pluripotent SCs give rise to multipotent SCs which continue the developmental process with more specific tasks (Figure, adapted from Spaas et al., 2012a). The blood contains 2 types of multipotent SCs: mesenchymal stem cells (MSCs) and hematopoietic stem cells (HSCs). In Global Stem cell Technology, we work with MSCs which have the capacity to form cartilage, bone, fat, muscle and tendon. This is in contrast with HSCs which have the ability to form all the different types of blood cells.