Chapter 4: The Effects of Nanoparticles on Bone Marrow Cells

This chapter reviews the observations made during the last decade in the area of nanoparticle effects on bone marrow cells such as nanoparticle biodistribution in the host including the bone marrow, nanoparticle-assisted imaging of the bone marrow, immunomodulatory effects, toxicity to bone marrow cells, and the use of nanoparticles for the radioprotection of the bone marrow. Depending on the nature of nanoparticles and their surface modifications, their biodistribution can be controlled to some extent, allowing the increase or decrease of their uptake into the bone marrow for the intended application. Magnetic resonance imaging with magnetic iron oxide nanoparticles has been gaining momentum with studies being conducted both in patients and animal models. Nanoparticles have proven to be useful in helping to induce the suppression or stimulation of the bone marrow as well as avoid the immunomodulatory effects of certain drugs altogether. The delivery of radioprotectors to the bone marrow by nanoparticles helps to enhance their radioprotective effect. Since the application of nanomaterials in biomedical research and medicine is a relatively new field, the most thorough evaluation of their potential toxicity, especially to the bone marrow, is paramount. While biodegradable nanoparticles in general lack bone marrow toxicity, metal and metal oxide nanoparticles vary in their effects on the bone marrow depending on the dose and route of administration, with TiO₂ particles having the highest cause for concern. Hence, research in this area should continue for any newly introduced nanomaterial.