Significant differences were observed between control and ALS sera in 20 factors (BDNF, PDGF-AB/BB, EGF, PDGF-AA, kallikrein 3, pentraxin 3, CD40 ligand, angiopoietin-2, CXCL12, uPAR, TfR, CXCL5, IFN-γ, MIF, Dkk-1, CD30, IL-11, IL-17A, IL-3, relaxin-2) (raw P < 0.05) but, as with fractalkine, the adjusted P value was not significant (Fig. 1 B). Here, CXCL12 is linked to amyotrophic lateral sclerosis.