Fig. 1

Serum titer of selected chronic traumatic encephalopathy (CTE) biomarker candidates. Blood samples of American football players (AFPs) were taken before (T0) and after (T1) an active season and compared to non-AFPs controls (CG). The serum/plasma was analyzed with ELISA for the titers of total Tau (tTau), phospho-Tau (pTau), neurofilament light protein (NF-L), glial fibrillary acidic protein (GFAP), Amyloid-β 40 (Aβ₄₀) and 42 (Aβ₄₂) and calcium binding protein B (S100-B). Additionally, the ratio of Aβ₄₀ and Aβ₄₂ was calculated. The distribution of the data was assessed with the Shapiro-Wilk test. Further statistical analysis was performed with either paired (AFP_T0 and AFP_T1) or unpaired t-test (AFP and CG) for normally distributed data or else Wilcoxon matched-pairs signed rank test (AFP_T0 and AFP_T1) and Mann Whitney-test (AFP and CG), respectively