Modulation of stem cell differentiation is of significant interest to the biomedical community and could lead to novel therapeutic advances in treating disease. Achieving this goal requires specific strategies that manipulate the pathways regulating stem cell plasticity and behavior. The accumulating evidence indicates that just a few main signaling pathways regulate most types of stem cells, which suggests that strategies that modulate one type of stem cell might hold broad usefulness. However, as stem cell research becomes more and more specialized, investigators studying a particular pathway in one specialty can miss a breakthrough advancement made in another specialty. Thus, the aim of this special issue is to take a pathway-focused approach to detail strategies—both proven and theoretical—that modulate the activity of stem-cell-relevant pathways (such as Wnt, TGF-beta, BMP, Notch, and FGF). We hope this special issue will advance the larger stem cell field by providing pathway-focused content including cutting-edge original research articles and accessible in-depth reviews that bridge investigators studying the same pathway in multiple stem cell populations.

Potential topics include, but are not limited to:

• Recombinant agonists or antagonists
• Engineered agonists/antagonists
• Gene transfer approaches
• Chemical agonists or antagonists
• Neutralizing antibodies
• Decoy receptors
• Engineered cell-based systems