UC Davis Children's Center Finds Signaling Disruptions in Mouse Cells from Mercury-Containing Vaccine Preservative
Researchers at the University of California at Davis Children's Center have found that low levels of thimerosal -- a vaccine preservative containing ethylmercury -- disrupt the signaling system between mouse dendritic (immune system) cells when observed in cell culture dishes. A paper from UC Davis in Environmental Health Perspectivesshows uncoupling of ATP-mediated calcium signaling between dendritic cells, which initiate the primary immune response, as well alterations to immune system function (abnormal increases in IL-6 cytokine secretion) from thimerosal in nanomolar concentrations (20 ppb) after only a few minutes of exposure. The release of these cytokines is a sign of inflammation. The study found that immature dendritic cells were especially sensitive. In the past, thimerosal was widely used in vaccines and although its use is now more limited to trace amounts in most children's vaccines, it is still used in multidose flu vaccines and some other vaccines such as diptheria and tetanus used only for adults. It is also used in some over-the-counter pharmaceutical products including ear and nose drops and cosmetics. UC Davis researchers are now planning to investigate effects of thimerosal on human cells sampled from children enrolled in the CHARGE study, which is examining factors which may be related to autism.
Paper in Environmental