Mocali et al found that plasma from AD subjects had reduced levels of TGF-β1 [9]; likewise, Huang et al saw a 30% reduction of TGF-β1 serum levels in AD patients but a non-significant reduction in serum from MCI patients [7] and those levels were found by Motta et al to vary by AD stage—viz, 8-fold higher in mild, 3.8-fold higher in moderate, and slightly reduced in severe stage disease [12]. Here, TGFB1 is linked to Alzheimer disease.