Searching for naïve human pluripotent stem cells

Figure 2 Maintenance of pluripotency by leukemia inhibitory factor and small molecules. Green arrows indicate activation, red blunted lines indicate inhibition. The pluripotent cell must self-renew without committing to any specific cell type. This may be achieved by promoting self-renewal and inhibiting commitment by LIF; or by small molecules (in italic) which inhibit (1) signaling through the FGF receptor tyrosine kinase, thus inhibiting commitment; and (2) GSK3, promoting self-renewal. Adapted from[33]. LIF: Leukemia inhibitory factor; FGFr: Fibroblast growth factor receptor-specific tyrosine kinase; GSK3: Glycogen synthase kinase 3; MEK: Mitogen-activated protein kinase.