FLG and Alzheimer disease: The average human filaggrin (±) SEM in patients’ sera with mild-moderate AD (n = 97), severe AD (n = 33), mild-moderate persistent AR (n = 83), severe persistent AR (n = 37), mild-moderate persistent BA (n = 93) and severe persistent BA (n = 52) was 6.58 ± 0.71, 12.14 ± 1.08, 4.69 ± 0.15, 8.31 ± 0.69, 6.68 ± 0.24 and 10.32 ± 0.51 ng/ml, respectively (Fig. 4a).