Evidence has emerged that excessive SP–NK1R or SP–MRGPRX2/B2 signals are implicated in the pathogenesis of many inflammatory disorders and associated organ injuries, such as sepsis-associated lung/liver/kidney injury, acute pancreatitis-associated lung injury, burn injury-associated lung injury, and chronic urticaria-related skin alterations (Figure 6). The gene discussed is MRGPRX2; the disease is Sepsis.