Foods Containing Pantoea agglomerans LPS Reduce Eye-Nose Allergies—A Double-Blind, Placebo-Controlled, Randomized, Parallel-Group Comparative Pilot Study

In this study, the effects of foods containing lipopolysaccharide (LPS) from Pantoea agglomerans (LPSp) on immunity were preliminarily investigated using a double-blind, placebo-controlled, randomized, parallel-group comparative study design. Thirty healthy subjects aged ≥ 20 years (four males and twenty-six females; mean age 49 ± 9.2 years) were randomly assigned to the LPS-containing food group (488 μg/day; LPS) or placebo group. Each food was consumed for 8 weeks, and a subjective survey of cold symptoms (Wisconsin Upper Respiratory Symptom Questionnaire) and allergic symptoms of the eyes and nose were conducted. Phagocytic capacity and lymphocyte counts were measured as indicators of immune function. There were no significant between-group differences with respect to any of the investigated items. On sub-group analysis of eye–nose allergy symptom score, confined only to subjects who reported eye–nose allergic symptoms in previous years, the LPS group showed a trend toward milder symptoms compared to the placebo group. In addition, when the symptom scores were compared only for subjects who developed eye–nose allergies during the study period, the LPS group showed significantly lower overall scores and eye symptom scores compared to the placebo group. These results suggest that the consumption of LPS-containing foods may alleviate or prevent eye–nose allergies. There were no statistically predominant changes in hematology and blood biochemistry tests, indicating that continued consumption of LPS-containing foods is safe. (UMIN000046154).