APP and Alzheimer disease: Interestingly, the treatment of 3xTg-AD mice with intravenous immunoglobulin (IVIg) reduces the accumulation of IL-12 and Th2 response/atopy-related IL-5 in the brain, but has no effect on GM-CSF levels, suggesting that anti-α4 treatment and IVIg therapy may have different effects on cytokine production.