[Clinical effects of Lactobacillus acidophilus strain L-55-contained yogurt on symptoms of Japanese cedar pollen allergy].

BACKGROUND: It has been reported that oral administration of Lactobacillus acidophilus strain L-55 (L-55) suppressed nasal symptom and antigen-specific IgE induced by antigen challenge in mice. We investigated clinical effects of L-55-contained yogurt on symptoms and IgE production in the patients with Japanese cedar pollinosis. METHOD: The study was performed as a randomized double blind placebo-controlled trial. L-55-contained yogurt (L-55 yogurt) or placebo yogurt was started to administer to each subject from 4 weeks prior to the onset of Japanese cedar pollen release for total 13 weeks. RESULT: The mean value of symptom score and symptom medication score were lower in L-55 yogurt group compared with placebo yogurt group during 5th week to 9th week from the first week of Japanese cedar pollination. Especially, in medicated subjects, total symptom score and throat symptom score were significantly lower in L-55 yogurt group compared with placebo yogurt group at 5th and 4th week from the first week of Japanese cedar pollination, respectively. Moreover, in medicated subjects, change ratio of serum total IgE was significantly lower in L-55 yogurt group compared with placebo yogurt group at 1st week from the first week of Japanese cedar pollination. CONCLUSION: Intake of L-55 during Japanese cedar pollinating season may be effective in alleviating the allergic symptoms related to Japanese cedar pollinosis. From these finding, it was suggested that L-55 is a possible candidate as a complementary medicine for Japanese cedar pollinosis.

Effect of Lactobacillus acidophilus strain L-55 on the development of atopic dermatitis-like skin lesions in NC/Nga mice.

In this study, we examined whether Lactobacillus acidophilus strain L-55 (strain L-55) suppresses the development of atopic dermatitis (AD)-like skin lesions induced by repeated application of 2,4,6-trinitrochlorobenzene (TNCB) in sensitized NC/Nga mice. The effect of strain L-55 was assessed by measuring clinical symptoms, ear swelling, scratching behavior and serum levels of total IgE. Strain L-55 was administered orally once a day: Strain L-55 at doses of 1 and 10 mg cells/mouse inhibited the development of AD-like skin lesions in dermatitis scores for the back. The increase of dermatitis score and ear swelling was also inhibited by strain L-55. In addition, strain L-55 also caused an inhibition of histological changes induced by repeated application of TNCB. Scratching behavior observed in the back and ear was inhibited by strain L-55. Furthermore elevated serum IgE levels observed by TNCB were also decreased by strain L-55. These results indicate that the inhibition of strain L-55 on AD-like lesions induced by repeated application of TNCB in sensitized NC/Nga mice occurred via a decrease in the serum total IgE level.

Effects of Lactobacillus acidophilus strain L-55 on experimental allergic rhinitis in BALB/c mice.

We investigated the effect of Lactobacillus acidophilus strain L-55 isolated from infant feces on experimental allergic rhinitis in BALB/c mice. The heat-treated cells of strain L-55 were orally administrated for 4 consecutive weeks to mice sensitized by ovalbumin (OVA), and nasal symptoms (sneezing and nasal rubbing) induced by OVA challenge were evaluated. Strain L-55 at doses of 1 and 10 mg cells/mouse significantly inhibited nasal symptoms by repeated administration over a period of 2 weeks. Furthermore, we measured the level of OVA-specific IgE titers in the serum by passive cutaneous anaphylaxis (PCA) reaction. PCA titers in the sera from mice administrated strain L-55 were significantly lowered compared with the control. These results suggest that oral administration of strain L-55 may be useful for alleviating the nasal symptoms of allergic rhinitis.