TLR8 and Alzheimer disease: A combination of S. typhimurium and miRNA may offer a more potent therapeutic modality in AD treatment than anti-TLR8miRNA alone, suggesting that TLR8 plays an important role in the restoration of Th2-skewed imbalance in AD and that S. typhimurium expressing TLR8 miRNA could potentially be used as an effective therapeutic modality for treating AD.