Authors

Discussion

The use of magnetic nanoparticles to produce heat (magnetic hyperthermia) has gained considerable interest in development of novel cancer therapies due to the increased sensitivity of cancerous cells to heat shock. In the current study, we are taking the first steps to establish whether magnetic hyperthermia could be used as an inducible, controlled and localised form of thermotherapy for cutaneous leishmaniasis.

Stable ferrofluids were produced by coating a range of iron oxide nanoparticles with citric acid. Uptake of nanoparticles by the human monocytic cell line THP-1 and L. mexicana axenic amastigotes was analysed by FerroZine assays, microscopy and flow cytometry. Magnetic hyperthermia was induced by the application of an alternating magnetic field and the resulting effects on cell viability and morphology were investigated. The magnetic nanoparticles were readily taken up by differentiated THP-1 cells and a controlled increase of temperature of up to 20°C could be achieved by application of an alternating magnetic field. Treatment with nanoparticles alone had a limited effect on viability of macrophages and amastigotes, whereas the subsequent induction of magnetic hyperthermia was found to be highly effective in killing parasites in vitro. Studies are ongoing to characterise the uptake, localisation and effects of magnetic nanaoparticles in THP-1 and L. mexicana amastigotes and to determine the effects of magnetic hyperthermia on L. mexicana infected macrophages.