Partial Least Squares - Discriminant Analysis (PLS-DA) of 212 metabolic biomarkers in 274 lupus and 214 healthy control PBL samples. A, Coefficient-based importance measures of the top 15 contributors to components 1, 2, and 3. B, 3-dimensional score plot of PLS-DA using components 1, 2, and 3, accounting for 28.3% and 29.2%, and 12.7% of total variance, respectively. C, Validation of PLS-DA by permutation tests.