Differentiation, distribution, and chemical state of intracellular trace elements in LAD2 mast cell line

Oxidation state changes of metallic ions are involved in the generation and biological defense against reactive oxygen species. The relationship between allergy and oxidative damage by metallic elements was studied by X-ray fluorescence analysis using a mast cell line. The distribution of metallic elements is changed by the induction of reactive oxygen species. In mast cells, the degranulation leading to antigen or calcium ionophore stimulation is related to excessive accumulation of iron and to its chemical state. X-ray absorption near-edge structure spectroscopy showed that the oxidation state of iron in the cells shifted from Fe(II) to Fe(III) in degranulation. This finding might have implications for understanding the mechanisms involved in IgE-mediated cell responses as seen in allergic reaction.