CD4 and End Stage Liver Disease: Foster et al. (2012) addressed the levels of CD4+ T cells expressing IL-17 and IL-22 in 11 patients with end-stage liver disease. They noted enrichment of IL-17A, IL-17F, and IL-22 secreting populations in liver compared to blood when analyzed ex vivo, although the overall levels of production in liver derived cells were similar to those in this study.