Micro-vesicles shed from stimulated cells[1] raise an increasing interest due to their potential for cancer therapy as cell-free vaccines[2] or to their role as “Trojan horses” to promote cell infection[3]. They are secreted by cells after fusion of specific intracellular compartments with plasma membrane. In that context, we intend to develop vesicles of intracellular origin which could transport magnetic nanoparticles and serve as multifunctional vectors for therapy. We assess the capability of the eukaryotic microorganism Dictyostelium discoideum to successively internalize superparamagnetic nanoparticles and release sub-micrometric vesicles loaded with these nanoparticles. Such biogenic vesicles were endowed with tracer qualities for magnetic resonance imaging, targeting properties by magnetic guidance and therapeutic potential through magnetically induced hyperthermia. Co-internalization by Dictyostelium of fluorescent dextran and magnetic nanoparticles led to the release of hybrid - fluorescent and magnetic – vesicles, suggesting the possibility to combine magnetic nanoparticles and antitumor drug in a single cell-derived vector.