Pre-symptomatic treatment with AP reduces EAE severity. C57BL/6 mice were immunized with 50 μg MOG35-55 in CFA and treated daily with 5 U AP or vehicle control from day 0 to 6 as indicated by arrows and shading (A, n = 9 control group; n = 10 AP-treated group), day 7 to 13 (B, n = 10) or day 14 to 20 (C, n = 10). Only mice treated early after immunization showed reduced clinical signs for EAE as compared to vehicle-treated mice. Shown are mean clinical scores ± sem. The cumulative EAE score in the pre-symptomatic treatment group was lower in AP-treated animals compared to controls (D, line indicates median). * P <0.05 Mann–Whitney U test. AP, alkaline phosphatase; CFA, complete Freund’s adjuvant; EAE, experimental autoimmume encephalomyelitis; sem, standard error of the mean.