Lactobacillus gasseri MG4247 and Lacticaseibacillus paracasei MG4272 and MG4577 Modulate Allergic Inflammatory Response in RAW 264.7 and RBL-2H3 cells.

Allergic inflammation refers to a hyperimmune reaction that causes hypersensitivity responses such as hives, itchiness, runny nose, and cough due to specific allergens. Allergic diseases are known to be influenced by the diversity and distribution of intestinal microbiota, and Lactobacill is known to relieve allergic symptoms by modulating cytokines secreted by T helper type 1 (Th1)/Th2 cells. This study was designed to investigate the effects of Lactobacillus gasseri MG4247 and Lacticaseibacillus paracasei MG4272, MG4577, and MG4657 on levels of pro-inflammatory cytokines and proteins associated with allergic symptoms in RAW 264.7 macrophages, and RBL-2H3 mast cells, as well as their probiotic properties. MG4247, MG4272, and MG4577 significantly reduced tumor necrosis factor-α and interleukin (IL)-6 levels in LPS-induced RAW 264.7 macrophages, and markedly decreased IL-4, IL-5, and IL-13 levels and STAT6 phosphorylation in DNP-IgE/HSA sensitized RBL-2H3 mast cells. Furthermore, MG4247, MG4272, and MG4577 tolerated the acidic condition with pepsin and basic condition with bile salt, and showed a high adhesion rate (≥ 73.9%). In safety evaluation, MG4247, MG4272, and MG4577 showed no hemolytic or bile salt hydrolase activity and no cytotoxicity to HT-29 cells (≥ 96.7%). Hence, MG4272, MG4272, and MG4577 can be used as candidate probiotic strains to relieve cytokines associated with allergic inflammation.