Quantities of KS in plasma were measured using a high-sensitivity KS ELISA kit. Oral tolerance was induced by feeding MKC mice with 50, 100, or 500 μg of peptide I10 (pink dots) or GALNS enzyme (blue dots). Control groups were fed with PBS (green and purple dots). One week after the last oral dose, mice received 16 weekly intravenous infusions of human GALNS (pink, blue, and green dots) or PBS (purple dots). Blood samples were obtained 10 days after the last infusion. Data are shown as scatter plots with mean ± 95% CI (n = 2–3 measurements for each mouse, n = 3 mice per group). *P < 0.05, Benjamini and Hochberg adjusted, for differences between tolerized and nontolerized (PBS-ERT) mice. §P < 0.05, Benjamini and Hochberg adjusted, for differences between ERT-treated mice and untreated (PBS-PBS) mice.