Role of monocytes and macrophages in experimental and human acute liver failure

Figure 2 Circulating monocytes express abundant cell surface HLA-DR. Initial exposure to LPS provokes a massive tumour necrosis factor-α (TNF-α) response. Repeated exposure to LPS or the presence of interleukin-10 (IL-10)/transforming growth factor-β (TGF-β) causes monocyte deactivation with downregulation of cell surface HLA-DR expression, impaired antigen presenting capability, and an attenuated TNF-α response to future LPS challenge.