In a recent study in Irritable Bowel Syndrome (IBS) patients, B. longum 1714 in combination with B. longum 35624TM improved anxiety and depression which was associated with a decrease in the pro-inflammatory cytokine TNF-α (Groeger et al., 2023).While B. longum 1714 does not seem to significantly alter gut microbiota composition in these studies (Moloney et al., 2021), it’s not clear what direct impact (if any) B. longum 1714 has on the immune system, and if so, which mechanisms are employed by the strain for this interaction. Here, TNF is linked to irritable bowel syndrome.