Toxic effects of heavy metals on the immune system: evidence from population and in vitro studies

The immune system of children is still in the developing stages and is more susceptible to threats from toxic heavy metals as compared with the immune system of adults. However, data on how heavy metal exposure affects the immune system in children, especially those who live in an e-waste-exposed area (Guiyu), is relatively scarce. My research includes population and in vitro studies. The former investigated exposure to heavy metals (lead, cadmium, mercury and arsenic) and their effects on the immune system of children living in this area. We found exposure to e-waste-originated heavy metals might impact the development and proliferation of immune cells in children, such as monocytes, eosinophils, neutrophils, basophil, NK cells and B cells. Our findings suggest that exposure to heavy metals in children induced aberrant immune homeostasis and inflammatory activation. The latter used cell lines of reporter cells (THP1-XBlue™-MD2-CD14, HEK-Blue™-hTLR2, 3, 4, 5, 7, 8 and 9) and immune cells (MonoMac 6 and Jurkat) to evaluate potential mechanisms by which heavy metals impact immune function. We conclude that the effects of heavy metals on TLRs, NF-κB pathways, MAPK pathways and mitochondrial function can explain the immunotoxicity of heavy metals.