The effect of probiotic use on ABO antibody titers.

The use of probiotics brings numerous benefits to the immune system, including an increase in antibody production. The development of ABO antibodies may occur naturally due to the bacteria of the intestinal microbiota. However, high titers of ABO antibodies can lead to hemolytic disease of the fetus and newborn and can cause immune transfusion reactions. In this context, this study aimed to evaluate the effect of probiotic consumption on ABO antibody titers in humans. ABO blood group, ABO antibody titer, and fecal pH and Bifidobacteria concentration were determined for 126 healthy individuals before and after daily consumption of yogurt containing Lactobacillus acidophilus and Bifidobacterium lactis over a 1-month period. No changes in fecal pH were observed after probiotic consumption, regardless of ABO blood group. There was, however, an increase in the fecal concentration of Bifidobacteria in individuals with blood group A but not for those with group B or O. A decrease in the titer of anti-B was observed, despite the increase in the concentration of Bifidobacteria in feces being unrelated to fecal pH, in blood group A individuals. Our study, therefore, sought to understand the relationship between probiotics and the antibody titer of the ABO blood system. Despite our findings, further human studies are needed with other probiotic strains and molecular analyses of the intestinal microbiota.