There are many ways by which pathogens can use host immune system for their own profit. One of those is to induce in the host an early IL-10 production. This early IL-10 production (observable in the sera of infected animals as soon as 1h after infection) blocks innate defense mechanisms, in particular neutrophil recruitment to infected sites, which allows systemic bacterial replication and may result in death.
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Article Inhibition of IL-10 Production by Maternal Antibodies agains...