Effect of tuftsin and its retro-inverso analogue on the release of interferon (IFN-γ) and tumor necrosis factor (TNF-α) by human leucocytes

Abstract The aim of this work was to demonstrate whether natural tuftsin or a retro-inverso (r.i.) analogue may induce interferon (IFN) and tumor necrosis factor (TNF) in peripheral-blood-mono-nuclear-cells (PBMC). For this purpose tuftsin or its analogue were added at different molar concentrations to PBMC and the supernatants were tested for IFN and TNF activity. Both cytokines were released after 12 hours incubation with r.i. tuftsin at an optimum concentration of 10 −10 M. Under the same conditions no activity was observed in the presence of natural tuftsin. In comparison to natural tuftsin the stimulatory activity of this tuftsin analogue is likely to be due to its high stability.