In a mouse model of ovalbumin (OVA)-induced asthma, intraperitoneal administration of IVIg from healthy human blood donors could induce antigen-specific peripherally generated Foxp3+ Treg cells even after selective depletion of pre-existing CD4+CD25+Foxp3+ Treg cells and inhibit Th2 responses and airway inflammation (42). This evidence concerns the gene FOXP3 and asthma.