Abstract: The present invention concerns methods and compositions utilizing gold nanoparticles for therapy for a medical condition, such as cancer. In particular aspects, the nanoparticles are included with or in a T cell to facilitate targeting of the nanoparticles to a desired location in vivo and/or to facilitate therapeutic treatment for the condition. In specific cases, the nanoparticle/T cell compositions further comprise microRNAs and/or peptides, and so forth.