Granulocyte-macrophage progenitor cells response to magnetite nanoparticles in a static magnetic field

The ability to modulate the life process of stem cells conjugated with MNPs via a magnetic field is promising as multifunctional tool in biomedicine. Experiment on mice demonstrates the high accumulation of iron ions measured via stripping voltammetry in the bone marrow in respect to bone, liver or kidney. Therefore, the potential cytotoxic effects of iron oxide magnetic nanoparticles (MNPs) on bone marrow cells become more predictable in comparison with the other examined cells. This study examined in vitro responses of mouse bone marrow-derived granulocyte-macrophage committed stem cells (colony-forming units of granulocytes and macrophages, CFU-GM) to a controlled amount of MNPs prepared by the exploding wire method; and to a moderate static magnetic field (SMF) of about 160 Oe. The moderate SMF did not affect CFU-GM capacity. Two different regimes of bone marrow cells cultivation with MNPs were investigated. Remarkably, adding MNPs to cells either decreased (1st cultivation regime, 6 pg MNPs per 1 cell) or enhanced (2nd regime, 20 pg MNPs per 1 cell) the colony-forming activity of CFU-GM, depending on the regimes of cultivation. The action of a moderate SMF on cells cultivated with MNPs inverts their effects on stem cell colony formation. Possible mechanisms of these phenomena are discussed. The main pathway was explained by a change in the presence of iron, either inside or outside of the cell, following the formation of free radicals susceptible to SMFs. Nanoscale magnetite activity within the pool of bipotent hemopoietic stem cells supports its proposed usage as supplement in cell technologies, theranostics, bone marrow repair and regenerative medicine. Further study is necessary to examine the intra- and intercellular mechanisms of the SMF's modulating effect on stem cell activity caused by magnetite MNPs.