Effects of Lactobacillus pentosus in Children with Allergen-Sensitized Atopic Dermatitis

Background@#Recent studies have shown that oral administration of probiotics may improve the immune imbalance caused by dysbiosis of the gut microbiome in atopic dermatitis (AD). This study aimed to investigate the clinical and immunological effects of Lactobacillus pentosus in children with mild to moderate AD. @*Methods@#Children aged 2–13 years with AD were randomized to receive either 1.0 × 1010 colony-forming units of L. pentosus or placebo, daily, for 12 weeks. The clinical severity of AD and transepidermal water loss were evaluated. Blood eosinophil counts, serum total immunoglobulin E (IgE), and cytokine levels were measured. The diversity and composition of the gut microbiota were also analyzed. @*Results@#Eighty-two children were recruited, and 41 were assigned to the probiotics intervention group. The mean scoring of atopic dermatitis (SCORAD) indices at baseline were 30.4 and 34.3 for the probiotics and placebo groups, respectively. At week 12, the mean indices were 23.6 and 23.1 for the probiotics and placebo groups, respectively. Clinical severity decreased significantly over time in both groups, with no significant difference between the two groups. In both groups, there were no significant differences in cytokine levels, microbial diversity, or the relative abundance of the gut microbiota at week 12 compared with the corresponding baseline values. The mean subjective scores of SCORAD indices after intervention for the probiotics group were significantly lower than those for the placebo group in IgE sensitized AD (P = 0.019). @*Conclusion@#Our results show improved symptoms in the probiotics and placebo groups, and we could not find additional effects of L. pentosus in AD. However, the mean subjective scores of SCORAD indices for the probiotics group are significantly improved compared with those for the placebo group in allergen-sensitized AD.

Lactobacillus pentosus Modulates Immune Response by Inducing IL-10 Producing Tr1 Cells

Several gut commensals have been shown to modulate host immune response. Recently, many food derived microbes have also been reported to affect the immune system. However, a mechanism to identify immunostimulatory and immunoregulatory microbes is needed. Here, we successfully established an in vitro screening system and identified an immunoregulatory bacterium, Lactobacillus pentosus KF340 (LP340), present in various fermented foods. LP340 induced a regulatory phenotype in mice Ag presenting cells which, in turn, induced IL-10 and IFN-γ producing Type 1 regulatory T cells (Tr1 cells) from naïve CD4⁺ T cells. Naïve CD4⁺ T cells co-cultured with LP340 treated dendritic cells highly expressed cytokine receptor IL-27R and were CD49b and lymphocyte-activation gene 3 double positive. Oral administration of LP340 in mice with atopic dermatitis reduced cellular infiltration in affected ear lobes and serum IgE levels, thus, ameliorating the disease symptoms. This suggests a systemic immunoregulatory effect of LP340. These findings demonstrate that LP340, a bacterium derived from food, prevents systemic inflammation through the induction of IL-10 producing Tr1 cells.

Baicalein, wogonin, and Scutellaria baicalensis ethanol extract alleviate ovalbumin-induced allergic airway inflammation and mast cell-mediated anaphylactic shock by regulation of Th1/Th2 imbalance and histamine release / 대한해부학회지

Asthma is characterized by chronic inflammation, goblet cell hyperplasia, the aberrant production of the Th2 cytokines, and eosinophil infiltration into the lungs. In this study, we examined the effects of baicalein, wogonin, and Scutellaria baicalensis ethanol extract on ovalbumin (OVA)-induced asthma by evaluating Th1/Th2 cytokine levels, histopathologic analysis, and compound 48/80-induced systemic anaphylaxis and mast cell activation, focusing on the histamine release from rat peritoneal mast cells. Baicalein, wogonin, and S. baicalensis ethanol extract also decreased the number of inflammatory cells especially eosinophils and downregulated peribronchial and perivascular inflammation in the lungs of mice challenged by OVA. Baicalein, wogonin, and S. baicalensis ethanol extract significantly reduced the levels of tumor necrosis factor α, interleukin (IL)-1β, IL-4, IL-5 and the production of OVA-specific IgE and IgG1, and upregulated the level of interferon-γ and OVA-specific IgG2a. In addition, oral administration of baicalein, wogonin, and S. baicalensis ethanol extract inhibited compound 48/80-induced systemic anaphylaxis and plasma histamine release in mice. Moreover, baicalein, wogonin, and S. baicalensis ethanol extract suppressed compound 48/80-induced mast cell degranulation and histamine release from rat peritoneal mast cells. Conclusively, baicalein and wogonin as major flavonoids of S. baicalensis may have therapeutic potential for allergic asthma through modulation of Th1/Th2 cytokine imbalance and histamine release from mast cells.

Analysis of Respiratory Motion Artifacts in PET Imaging Using Respiratory Gated PET Combined with 4D-CT / 대한핵의학회잡지

PURPOSE: Reduction of respiratory motion artifacts in PET images was studied using respiratory-gated PET (RGPET) with moving phantom. Especially a method of generating simulated helical CT images from 4D-CT datasets was developed and applied to a respiratory specific RGPET images for more accurate attenuation correction. MATERIALS AND METHODS: Using a motion phantom with periodicity of 6 seconds and linear motion amplitude of 26 mm, PET/CT (Discovery ST; GEMS) scans with and without respiratory gating were obtained for one syringe and two vials with each volume of 3, 10, and 30 ml respectively. RPM (Real-Time Position Management, Varian) was used for tracking motion during PET/CT scanning. Ten datasets of RGPET and 4D-CT corresponding to every 10% phase intervals were acquired. From the positions, sizes, and uptake values of each subject on the resultant phase specific PET and CT datasets, the correlations between motion artifacts in PET and CT images and the size of motion relative to the size of subject were analyzed. RESULTS: The center positions of three vials in RGPET and 4D-CT agree well with the actual position within the estimated error. However, volumes of subjects in non-gated PET images increase proportional to relative motion size and were overestimated as much as 250% when the motion amplitude was increased two times larger than the size of the subject. On the contrary, the corresponding maximal uptake value was reduced to about 50%. CONCLUSION: RGPET is demonstrated to remove respiratory motion artifacts in PET imaging, and moreover, more precise image fusion and more accurate attenuation correction is possible by combining with 4D-CT.