Figure 2.

Different sources of stem cells and their mechanism of differentiation for cell-based therapies. ESCs (A) are isolated from the early blastocyst [61]. The sources of HSCs (B) and MSCs (C) include placenta, umbilical cord, bone marrow, and peripheral blood; for MSC, additionally, dental pulp, muscle, and adipose tissue can be utilized [60,83]. iPSCs (D) are derived from somatic cells by a reprogramming step. Triggered by different transcription and growth factors, all of them can be differentiated into hepatocytes.