In canines with idiopathic IBD, treatment with the probiotic cocktail containing Lactobacillus, Bifidobacterium, and Streptococcus sulivarius significantly reduced clinical symptoms by reducing CD4+ cell infiltrate, increasing the population of Foxp3+ Tregs, and increasing occludin and claudin 2 expressions in the intestinal mucosal tissue (Rossi et al., 2014). Here, CD4 is linked to inflammatory bowel disease.