The invention disclosed provides populations and compositions of mesenchymal stem and progenitor cells derived from adult tissues that are subjected to a process or processes designed to enhance a biological mechanism prior to implantation of the cells for therapeutic use. The processes involve preconditioning of said mesenchymal stem cells with a physiological stressor in vitro, so as to enhance therapeutically significant biological properties. Specific embodiments of the invention include stimulation of angiogenic and immune modulatory properties by preconditioning with interferon-gamma, as well as other physiologically-relevant stressors such as activation of toll like receptors. Immunologically-relevant properties of preconditioned cells including the treatment of cytokine storm associated with sepsis, or viral infection. In the angiogenic embodiment of the invention, cells are used for the treatment of peripheral artery disease, its advanced form, critical limb ischemia, or ischemic heart failure.
