CD40LG and inflammatory bowel disease: As a co-stimulatory molecule, CD40L is essential for T cell activation; although prior studies predominantly emphasize its pro-inflammatory roles, the observed reduction in its levels in IBD patients may reflect impaired regulatory T cell activity or dysregulation of immune tolerance.[31] The results of this study confirm the causal relationship between CD40 and IBD, further supporting the CD40/CD40L signaling pathway as a novel therapeutic target for IBD.