Figure 3.

IFN-γ production in co-culture experiments. The data shown are representative examples from six separate living donor experiments. Freshly isolated human LMNCs, LMNCs depleted of CD14⁺ cells, NK cells, and NK cells co-cultured with Kupffer cells together and separated by a transwell were stimulated by TLR agonists for 16 h. Medium and IL-12/15 served as negative and positive control, respectively. Cells were stained with antibodies for cell-surface CD3, CD56, and CD16 and for intracellular IFN-γ. Results show intracellular IFN-γ in CD3⁻, CD56⁺ NK cells. The synthesis of IFN-γ in NK cells was dependent on direct contact with Kupffer cells.