Using the IVW approach, we found no statistically significant association between IBD and any of the 5 immune cell traits (HLA-DR on CD14+ monocytes: OR: 0.956, 95% CI: 0.856–1.067, CD39+ CD4+ T cells: OR: 1.028, 95% CI: 0.961–1.099; Fig. 4). Here, CD4 is linked to irritable bowel syndrome.