VIP and asthma: Knowing that Treg are a critical cell type to engage in order to induce tolerance in allergic individuals, and having the availability of VIP knockout (VIP KO) mice--a spontaneous model of asthma (airway inflammation and airway hyper-responsiveness not requiring allergic sensitization)--we were uniquely positioned to validate the role of VIP in Treg expression from central thymus and peripheral spleen in the VIP KO mice, untreated and treated with exogenous VIP replacement.