Viable and Heat-Killed Probiotic Strains Improve Oral Immunity by Elevating the IgA Concentration in the Oral Mucosa

Abstract

Oral-nasal mucosal immunity plays a crucial role in protecting the body against bacterial and viral invasion. Safe probiotic products have been used to enhance human immunity and oral health. In this study, we verified the beneficial effects of mixed viable probiotic tablets, consisting of Lactobacillus salivarius subsp. salicinius AP-32, Bifidobacterium animalis subsp. lactis CP-9, and Lactobacillus paracasei ET-66, and heat-killed probiotic tablets, consisting of L. salivarius subsp. salicinius AP-32 and L. paracasei ET-66, on oral immunity among 45 healthy participants. Participants were randomly divided into viable probiotic, heat-killed probiotic, and placebo groups. The administration of treatment lasted for 4 weeks. Saliva samples were collected at Weeks 0, 2, 4, and 6, and Lactobacillus, Bifidobacterium and Streptococcus mutans populations and IgA concentration were measured. IgA concentrations, levels of TGF-beta and IL-10 in PBMCs cells were quantified by ELISA method. Results showed that salivary IgA levels were significantly increased on administration of both the viable (119.30 ± 12.63%, ***P < 0.001) and heat-killed (116.78 ± 12.28%, ***P < 0.001) probiotics for 4 weeks. Among three probiotic strains, AP-32 would effectively increase the levels of TGF-beta and IL-10 in PBMCs. The oral pathogen Streptococcus mutans was significantly reduced on viable probiotic tablet administration (49.60 ± 31.01%, ***P < 0.001). The in vitro antibacterial test confirmed that viable probiotics effectively limited the survival rate of oral pathogens. Thus, this clinical pilot study demonstrated that oral probiotic tablets both in viable form or heat-killed form could exert beneficial effects on oral immunity via IL-10, TGB-beta mediated IgA secretion. The effective dosage of viable probiotic content in the oral tablet was 109 CFUs/g and the heat-killed oral tablet was 1 × 1010 cells/g.

The Effect of Oral Probiotics (Streptococcus Salivarius k12) on the Salivary Level of Secretory Immunoglobulin A, Salivation Rate, and Oral Biofilm: A Pilot Randomized Clinical Trial

“…Probiotics demonstrated beneficial effect on host immune response [ 48 ], although studies of the effect of probiotics on sIgA levels have shown conflicting results. Some studies found increased levels of salivary sIgA in adults [ 44 , 47 , 49 , 50 , 51 ], elderly patients [ 52 ], and children [ 47 , 48 ] after probiotic intake, while others were unable to confirm such findings [ 23 , 53 , 54 , 55 , 56 ]. One study even demonstrated a decrease in salivary sIgA after Bifidobacterium-containing probiotic intake [ 57 ].…”

Impact of the food grade heat-killed probiotic and postbiotic oral lozenges in oral hygiene

“…Based on previous findings that probiotic strains of AP-32, ET-66 and LPL28 effected oral microbiota [ 23 ] and viable strains may improve salivary IgA via up-regulating anti-inflammatory cytokines, IL-10 and TGF-beta [ 35 ]. Besides, a previous animal study discovered the mixed viable probiotic strains of Lactobacillus salivarius subsp.…”

Adjuvant probiotic Bifidobacterium animalis subsp. lactis CP-9 improve phototherapeutic treatment outcomes in neonatal jaundice among full-term newborns: A randomized double-blind clinical study

“…Probiotics with a long history of safe use in foods or those obtained from healthy gastrointestinal tracts are unlikely to harm the human body, such as Lactobacillus species ( acidophilus , casei , fermentum , gasseri , johnsonii , paracasei , plantarum , rhamnosus , and salivarius ) and Bifidobacterium species ( adolescentis , animalis , bifidum , breve , and longum ). [ 32 ] Studies have reported various functions of B. animalis CP-9, such as inhibition of extended-spectrum β-lactamase–producing E. coli [ 33 ] ; inhibition of pathogenic group B Streptococcus , which is highly correlated with newborn survival rate [ 34 , 35 ] ; suppression of pathogenic Staphylococcus aureus , which may cause infant atopic dermatitis [ 36 , 37 ] ; protection against oral pathogens to improve oral immunity in subhealthy adults [ 38 , 39 ] ; and reduction of inflammation and glycemic index in a type 2 diabetes animal model. [ 40 ] In the present study, food-grade probiotic strain B. animalis CP-9 in synergy with phototherapy was effective in NJ treatment.…”