In co-infection experiments, mice were infected with H. polygyrus and at peak expansion of resident peritoneal MΦ SL3261 was inoculated i.p. Cell-intrinsic plasticity of the M(IL-4) MΦ was observed in response to bacterial infection but plasticity did not appear relevant for protection within the first 5 days of SL3261 infection. Here, IL4 is linked to coinfection.