CD4 and breast cancer: (113) demonstrated that oral administration of Lactobacillus reuteri ATCC-PTA-6475 was sufficient to inhibit mammary carcinogenesis in outbred Swiss mice at increased risk of development of mammary tumors due to the feeding of a Westernized diet (high fat, low fibers), and to delay or completely prevent tumor onset in MMTV-neu mutant FVB mice, genetically predisposed to develop mammary tumors, through the induction of anti-inflammatory CD4+ CD25+ Tregs.