There was a clear trend towards an increase in TNFR1 protein levels (Ctrl: 1.08 ± 0.31, AD: 2.18 ± 0.31; p = 0.063), which did not reach significance due to substantial heterogeneity between cases, but no difference in TNFR2 levels (Fig. 5b, c). Here, TNFRSF1B is linked to Alzheimer disease.