Letter to the Editor: Unlinking lymphocyte counts from disease severity in patients with acute-on-chronic liver failure

Figure 1 Possible mechanisms underlying T-cell immune exhaustion in acute-on-chronic liver failure include persistent antigenic stimulation, metabolic abnormalities (such as mitochondrial damage), increased numbers of immunosuppressive cells, increased expression of inhibitory receptors, and elevated levels of immunosuppressive cytokines. These factors ultimately lead to uncontrolled infection and inflammation, thus creating a vicious cycle. Created with http://biogdp.com. CTLA-4: Cytotoxic T-lymphocyte-associated protein 4; HBV: Hepatitis B virus; IL-10: Interleukin-10; MDSCs: Myeloid-derived suppressor cells; PD-1: Programmed death 1; TGF-β: Transforming growth factor-beta; Tregs: Regulatory T cells.