2.5 Drug Allergies
Drug allergies (DAs) may be IgE- or non-IgE-mediated. Some drugs, such as anaesthetics, antibiotics, nonsteroidal anti-inflammatory drugs and codeine, are associated with a carrier protein through a prototype or its metabolite.50 Binding of cell-bound IgE molecules activates mast cells and releases various factors, such as histamines, leukotrienes, prostaglandins and cytokines, which can cause extensive tissue damage. Trx1 is a stress-induced redox regulatory protein in vivo ; thus, it inhibits histamine release by eliminating ROS in mast cells.51 The mechanisms of DAs may often be associated with non-IgE-mediated complement activation. Indeed, Trx1 is known to inhibit the activation of the complement cascade at different stages, e.g. suppressing C3 cleavage and C5 convertase activation.52,53 The functions of Trx1 in mast cells and the complement system are described in the next section.