SYT17 and Atrophy: Synaptotagmin-17 (SYT17) levels were higher in an exosomal fraction of urine from chronic active antibody-mediated rejection patients compared with three other histology groups (normal, interstitial fibrosis and tubular atrophy, and calcineurin inhibitor toxicity), and this was linked to the activation of the IL-6 amplifier [148].