IL21 and infection: The PLS showed that the levels of GMCSF, Fractalkine, IFNg, ITAC, IL-1ß, IL-2, IL-5, IL-7, IL-8, IL-10, IL-12, IL-17α, IL-21, IL-23, MIP-1ß, and TNFα had higher impact on the separation between the uninfected and the pre-infection cohort (Fig. 2b and Additional file 4: Table S3 A).