This detailed book collects original protocols aimed at encouraging and stimulating the scientific community to design and produce models for the laboratory that mimic cell guidance conditions as they occur in vivo. The protocols collected describe powerful strategies to exploit chemical cues involved in cell differentiation processes. Special emphasis is given to the use of methods for purification and characterization of exosomes and other secreted vesicles, as well as micro and non-coding RNAs, that have been demonstrated to control the tuning of the in vivo micro and macro environment in order to ensure the optimal soluble environment in vitro. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.