Research suggests that gut bacteria play a role in controlling immune responses, with some studies indicating that gut bacteria can inject proteins to influence the immune system. However, the relationship between the gut microbiome and the immune system appears to be complex and bidirectional, with the immune system also maintaining the balance of the microbiome. The interaction between the gut microbiome and the immune system may have implications for various health conditions, including inflammation, immune-mediated diseases, and overall well-being.