In addition, deficiencies of brain-derived neurotrophic factor (BDNF) have a role in depression, anxiety and other neuropsychiatric illnesses.55, 56 Indeed, the acute behavioral effects of SSRIs and tricyclic antidepressants seem to require BDNF signaling,57 suggesting that BDNF holds great potential as a therapeutic agent.58 Cell therapies focused on correcting BDNF deficiencies in mice have had some success. After a chronic stressor challenge, mice treated with human iPSC-derived neural progenitors overexpressing BDNF experienced greater neurogenesis than control mice.59 Thus, it is conceivable that iPSC-derived cells with inducable BDNF expression may one day be used in a form of cell-based therapy for psychiatric patients.