薬理と治療

Abstract

Objectives　Lactobacillus paracasei K71（L. paracasei K71）has anti-allergic capacity such as T helper 1（Th1）polarization in mouse splenocytes and IgE level suppression in ovalbumin （OVA）-immunized mouse serum. We investigated the palliative effects of L. paracasei K71 intake on Japanese cedar（JC）pollen allergy in a randomized, double-blind, placebo-controlled, parallel-group trial in an environmental exposure unit（EEU）. Methods　Fifty subjects with JC pollen-specific IgE were enrolled in this trial. Subjects（n＝25 per group）were allocated randomly and ingested two tablets containing 50 mg（approximately 1×1011 bacteria）of L. paracasei K71（group A）or placebo（group P）daily for 8 weeks. Before and after intake period, subjects were exposed to JC pollen for 3 hours and answered a questionnaire about pollinosis symptoms in the EEU. The questionnaire was continued for 4 days after JC pollen exposure. Results　One subject withdrew, another met an exclusion criterion, and 48 subjects were included in the efficacy analysis. Number of nose blows（30 min）and nasal congestion score （30 and 60 min） in EEU were significantly suppressed in group A. Additionally, number of sneezes （day 2）and sore or scratchy throat score（day 3）after JC pollen exposure were significantly suppressed in group A. Conclusions　The results suggest that the continuous intake of L. paracasei K71 palliates nasal and throat discomfort during and after JC pollen exposure. （UMIN ID: 000037571）