by Barry Fitzgerald , Eindhoven University of Technology

When something is awry with your immune system, your digestion or your endocrine systems, nuclear receptors, as they are called, may well be involved. If need be, the operation of these regulator proteins can be altered with medicinal drugs, but this carries the very real risk of unpleasant side effects. Doctoral candidate Femke Meijer looked for—and found—molecules that might well be used as medications for autoimmune diseases, but with fewer side effects. Meijer defends her thesis at the department of Biomedical Engineering on June 23.

Our body has exactly 48 types of nuclear receptor. These are proteins that float about in our cells and can be activated by all sorts of signal molecules such as hormones. When this happens, the nuclear receptor in question issues an instruction in the cell nucleus to produce other particular proteins. Shutting down or conversely activating these nuclear receptors is the mechanism by which one in six medicines achieves its intended effect. The best-known example is most probably the contraceptive pill. “This acts on the estrogen and progesterone receptors,” says doctoral candidate Femke Meijer.

As part of her research, Meijer studied another nuclear receptor, RORỿt, which regulates the production of cytokines and as such plays a role in the genesis of inflammatory reactions. Certain drugs for autoimmune diseases, such as rheumatism, psoriasis, asthma, and Crohn’s disease, turn this function to their advantage and aim to shut down this nuclear receptor. “They do this by blocking what’s known as its binding site with a molecule, so that this particular nuclear receptor, RORỿt, is deactivated,” explains Meijer.