Increasing salivary IgA and reducingby probioticSD1: A double-blind, randomized, controlled study.
J Dent Sci. 2019 Jun ;14(2):178-184. Epub 2019 Mar 27. PMID: 31210892
Background/purpose: Our previous study revealed that probioticSD1 could reduce mutans streptococci as evaluated by cultivation-method as well as stimulate innate immunity. This study aimed to further investigate the effect of the probiotic on various oral bacteria by real-time PCR and salivary IgA levels.
Materials and methods: Forty children were included by randomization from either probiotic or control group in the previous study. The probiotic or control received milk-powder with or without.SD1, respectively once daily for 6 months. Saliva were collected at baseline 3-, 6-, and 12-months and were evaluated for total bacteria, total lactobacilli (TL),(LP/LC), total streptococci (TS) andusing the real-time PCR. The salivary IgA (sIgA) was examined using the ELISA method.
Results: All target bacterial levels were not significantly different at baseline in both groups. After milk-powder consumption, TL and LP/LC levels were significantly increased in the probiotic group, whereas TS andlevels were significantly decreased compared to baseline. TS andlevels were significantly lower, while the sIgA was greater in the probiotic compared to the control group. In the probiotic group, a positive correlation was found between LP/LC and sIgA, while negative correlations were observed between TS orlevels and sIgA.
Conclusion: SD1 could controllevel and could stimulate sIgA. Results indicate that theSD1 strain may have a benefit for prevention of dental caries.