A therapeutic or diagnostic delivery vehicle is provided. The delivery vehicle may include one or more particles, such as microparticles, nanoparticles and stimuli-responsive particles, conjugated to a tropic cell that targets at least one pathological entity or site. In addition, a pharmaceutical composition is provided. The pharmaceutical composition may include, among other things, a particle conjugated to a tropic cell such as those discussed above and at least one diagnostic or therapeutic agent, such as those described herein. In some aspects, the tropic cell may target at least one pathological entity or site. Further, methods for diagnosing, monitoring or treating a pathological condition in a subject are provided. Such methods may include administering a therapeutically effective amount of the pharmaceutical composition to a subject.