A probiotic formulation containing Lactobacillus bulgaricus DWT1 inhibits tumor growth by activating pro-inflammatory responses in macrophages

Abstract Probiotics are functional foods and are becoming more evident with time that probiotics can have prophylactic and therapeutic roles. Current report revealed that an established probiotic cocktail of Lactobacillus delbruckei sp. bulgaricus DWT1 and Streptococcus thermophilus DWT4, could inhibit tumor growth. This probiotic cocktail is already marketed in various forms of food supplement. Present report reveals the transition of M2 to M1 like state of macrophage cells of mouse origin in vitro, ex vivo and in vivo following treatment with the established probiotic cocktail. Current study for the first time suggests the ability of a probiotic formulation to polarize macrophages from M2 to M1 state with potentials of developing newer intervention strategies for tumor growth. As a validation of our claim, we have established a novel and significant way of tumor inhibition in mouse model by the probiotic formulation that is capable of polarizing macrophages from M2 to M1.