Protocol to photoactivate adipose-derived stem cell differentiation using a tightly-focused femtosecond laser

The technology to induce stem cell differentiation is of great importance in life science, stem cell therapy, and regenerative medicine. Here, we detail steps to noninvasively activate stem cell differentiation in vitro and in vivo using a tightly focused femtosecond laser. We describe how a single-time transient photoactivation can initiate differentiation without any gene engineering, exogenous substances, or physical contact. This protocol enables the differentiation of adipose-derived stem cells to osteoblasts in vitro and cerebellar granule neuron progenitors to granule neurons in vivo. For complete details on the use and execution of this protocol, please refer to Tang et al. (2022).