Multiple allergic reactions traced to single protein
Johns Hopkins and University of Alberta researchers have identified a single protein as the root of painful and dangerous allergic reactions to a range of medications and other substances. If a new drug can be found that targets the problematic protein, they say, it could help smooth treatment for patients with conditions ranging from prostate cancer to diabetes to HIV. Their results appear in the journal Nature on Dec. 17.
Previous studies traced reactions such as pain, itching and rashes at the injection sites of many drugs to part of the immune system known as mast cells. When specialized receptors on the outside of mast cells detect warning signals known as antibodies, they spring into action, releasing histamine and other substances that spark inflammation and draw other immune cells into the area. Those antibodies are produced by other immune cells in response to bacteria, viruses or other perceived threats.
However, “although many of these injection site reactions look like an allergic response, the strange thing about them is that no antibodies are produced,” says Xinzhong Dong, Ph.D. , an associate professor of neuroscience in the Institute for Basic Biomedical Sciences at the Johns Hopkins University School of Medicine.
Caption: This is a mast cell. Credit: Priyanka Pundir/University of Alberta