As research has shown, the inflammatory infiltrate of AD contains eosinophils and the neurotoxins they release, and their amount determines the severity of the disease, hence the concept that IL-5, as the main cytokine influencing the development and functions and prolonging the lifespan of eosinophilia (by inhibiting the apoptosis process), may be the target of biological drugs used in AD. The gene discussed is IL5; the disease is Alzheimer disease.