MRGPRX2 and Alzheimer disease: Interestingly, given that more than 90% of AD patients present Staphylococcus aureus colonization in the affected skin areas, recent investigations have shown that the Staphylococcus δ-toxin provokes MC degranulation via MRGPRX2 and that the compound QWF, a MRGPRX2 antagonist, inhibits this activation [74].