Specific cells cause inflammation when they receive a signal from another cell.
This substance is normally broken down by members of a large family of enzymes called phosphodiesterases. So, if the activity of these phosphodiesterases can be inhibited, cyclic AMP levels will rise and the generation of the inflammatory signal blocked, allowing inflammation to be controlled. Drug companies have already demonstrated that diseases such as asthma and rheumatoid arthritis can be controlled by drugs which inhibit phosphodiesterases. However, such treatments have unwanted side effects because these drugs inhibit other phosphodiesterases as well as those which control inflammation. Professor Houslay is looking for ways of controlling the activity of just those phosphodiesterases which are specifically involved in inflammation processes in order to make highly specific medicines for treating asthma and rheumatoid arthritis without them having unwanted side effects.