Fig. 2

Defenses mechanisms against H. pylori infection which subdivided into two main mechanisms including physiological barriers and immune system. Upon entrance of H. pylori into the stomach, both innate and specific immunity enter the area of infection (lamina propria). Consumption of probiotics has several advantages in strengthening and stimulating immune system versus this pathogen. Antibacterial activities of probiotics direct and indirect are helpful for human health. Therapeutic effects of these bacteria in gastric tract are including immune modulation (via interaction with TLRs), anti-H. pylori activity, co-aggregation of invasive bacteria, decrease pH by secretion of short chain fatty acids, support epithelial barrier integrity, mucin production, as well as promoting immune cells to inhibit gastric inflammatory response particularly IL-8 production, and induction of immunoglobulin secretions