ROS-producing macrophages in immune modulation

Abstract

Anti-inflammatory Mph have a high plasticity. Both in vivo and in vitro different types of Mph2 have been observed, all presenting an overlapping phenotype, but each having specific characteristics. Classifying Mph2 is difficult, especially since no specific markers for human Mph2 have yet been identified. At present, the full mechanism by which Mph-derived ROS affect T cell activation and signaling is unknown. We observed that Mph2 activate T cells in a ROS-dependent manner but also that the suppression of activated T cells by Mph2 was ROS-dependent. We observed that some cytokines were affected by DPI: the IL-12p40 and IL-10 production were suppressed by DPI, whereas no effect was observed with IL-6, suggesting that ROS is specifically involved in the regulation of some cytokines that may exert its effect on T cells. These results can be a new start point for further research in unraveling the mechanism, but how ROS affects T cell activation will need further investigations. In summary, T cells are activated by Mph-derived ROS and regulation of the cytokine production by the APC is a potential mechanism how ROS can affect T cell functions