CD6 and Sepsis: In the context of sepsis leading to 28-day mortality, significant associations were found for the relative count of CD28+ DN Treg cells within T-cells, the morphological parameter SSC-A on B-cells, the MFI of HLA DR on HLA DR+ NK cells, and CD25 on IgD+ B-cells, which are mediated by the levels of the T-cell surface glycoprotein CD6 isoform, cystatin D, interleukin-18 (IL-18), and urokinase-type plasminogen activator (uPA), respectively (Table 2).