MAPT and Alzheimer disease: In addition to the well-recognised AD-associated pathologies and argyrophilic grains in argyrophilic grain disease (AGD) [11], various studies have demonstrated that the dense granules of granulovacuolar degeneration (GVD) also react with tau antibodies directed against various epitopes [10, 12–15] but not those directed against some conformational epitopes specific for PHFs [16, 17].