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- Abrahamsson, Thomas, 1968-
(författare)
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Can Lactobacillus Reuteri Prevent Allergic Disease in Early Childhood?
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: An altered microbial exposure may be partly responsible for the increase of allergic diseases in populations with a western lifestyle. Activation of the immune system by microbes early in life is probably required for an accurate maturation of the immune system. Probiotics, live bacteria which are considered to confer health when ingested, have been suggested to prevent eczema and sensitisation infants.Aim: The general aim of this thesis was to assess the effect of oral supplementation with the probiotic bacterium Lactobacillus reuteri (L. reuteri) in infancy on the development of allergic disease and sensitisation during the first 2 years of life and to examine mechanisms possibly underlying eventual effects on allergic manifestations.Subjects: The thesis is based on results obtained from a prospective double-blind placebo-controlled multicenter trial, comprising 232 families with allergic disease, of whom 188 completed the study.Methods: The families were recruited at the antenatal clinic, and the mothers received L. reuteri ATCC 55730 (1 x 108 colony forming units) or placebo daily from gestational week 36 until delivery. Their babies then continued with the same study product from birth until 12 months of age and were followed up for another year. The primary outcomes were allergic disease, with or without positive skin prick test or circulating IgE to food allergens. Bacterial counts and prevalence were assessed in maternal breast milk and faeces and infant faeces, employing conventional cultivation methods. Cytokines and IgA antibodies were analysed in colostrum and mature milk from the mothers with ELISA, and Na/K- ratio in breast milk with ion selective electrodes. Circulating Th1/Th2-associated chemokines were analysed in cord and peripheral blood in the infants with Luminex or ELISA technique.Results: The incidence of eczema was similar, 36% in the treated versus 34% in the placebo group. The L. reuteri group had a lower cumulative incidence of IgE-associated allergic disease, 20% versus 35% (p=0.04), and less IgE-associated eczema during the second year, 8% versus 20% (p=0.02). The prevalence of L. reuteri was higher during the first year of life in stool samples from infants, as well as in colostrum, in the active as compared to the placebo treated group. Colostrum from L. reuteri supplemented mothers had lower levels of TGF-β2, and low levels of this cytokine were associated with less sensitisation. Low Th1- and high Th2-associated chemokine levels preceded allergic disease. The presence of L. reuteri in stool was associated with lower levels of the Th2-associated chemokines CCL17 and CCL22 and higher levels of the Th1-associated CXCL11.Conclusion: Although a preventive effect of probiotics on infant eczema was not confirmed, the L. reuteri treated infants had lower incidence of IgE-associated allergic disease at two years of age, and therefore possibly run a reduced risk to develop later respiratory allergic disease. The mechanisms underlying this effect require further elucidation.
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| 2. |
- Abrahamsson, Thomas R, et al.
(författare)
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Probiotic lactobacilli in breast milk and infant stool in relation to oral intake during the first year of life
- 2009
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Ingår i: Journal of pediatric gastroenterology and nutrition. - : Lippincott Williams & Wilkins. - 1536-4801 .- 0277-2116. ; 49:3, s. 349-354
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: This is to identify factors affecting the prevalence of Lactobacillus reuteri in maternal faeces and breast milk and infant faeces after oral supplementation with L reuteri and to assess the influence on microbial ecology, particularly Clostridium difficile and Bifidobacterium colonization. MATERIALS AND METHODS: In this double-blind trial, 232 mothers with a family history of atopic disease were randomized to a daily intake of either L reuteri American-type culture collection (ATCC) 55730 (1 x 10 colony-forming units [CFU]) or placebo for the last 4 weeks of pregnancy. Their babies then continued with the same study product daily from birth until 12 months of age. Bacterial counts and prevalence were assessed in maternal breast milk and faeces and infant faeces, using conventional cultivation methods. RESULTS: The prevalence of L reuteri was higher during the first year of life in the stool samples from infants in the active as compared with the placebo-treated group. The highest prevalence was recorded at 5 to 6 days of age (82% in the treated vs 20% in the placebo group, P < 0.001). Lactobacillus reuteri was isolated from 12% and 2%, respectively, in the colostrum samples (P < 0.05). Breast-feeding seemed to reduce faecal L reuteri counts, although antibiotics did not influence the levels of L reuteri. The administration of L reuteri did not affect bifidobacteria or C difficile colonization. CONCLUSION: Lactobacillus reuteri may be detected in breast milk after oral supplementation to the mother and in almost all infants after oral supplementation during the first year of life, as well as occasionally in many untreated infants.
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| 3. |
- Abrahamsson, Thomas R, 1968-, et al.
(författare)
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Probiotics in prevention of IgE-associated eczema : a double-blind, randomized, placebo-controlled trial
- 2007
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Ingår i: Journal of Allergy and Clinical Immunology. - : Elsevier BV. - 0091-6749 .- 1097-6825. ; 119:5, s. 1174-1180
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: An altered microbial exposure may underlie the increase of allergic diseases in affluent societies. Probiotics may alleviate and even prevent eczema in infants. OBJECTIVE: To prevent eczema and sensitization in infants with a family history of allergic disease by oral supplementation with the probiotic Lactobacillus reuteri. METHODS: Double-blind, randomized, placebo-controlled trial, which comprised 232 families with allergic disease, of whom 188 completed the study. The mothers received L reuteri ATCC 55730 (1 x 10(8) colony forming units) daily from gestational week 36 until delivery. Their babies then continued with the same product from birth until 12 months of age and were followed up for another year. Primary outcome was allergic disease, with or without positive skin prick test or circulating IgE to food allergens. RESULTS: The cumulative incidence of eczema was similar, 36% in the treated versus 34% in the placebo group. The L reuteri group had less IgE-associated eczema during the second year, 8% versus 20% (P = .02), however. Skin prick test reactivity was also less common in the treated than in the placebo group, significantly so for infants with mothers with allergies, 14% versus 31% (P = .02). Wheeze and other potentially allergic diseases were not affected. CONCLUSION: Although a preventive effect of probiotics on infant eczema was not confirmed, the treated infants had less IgE-associated eczema at 2 years of age and therefore possibly run a reduced risk to develop later respiratory allergic disease. CLINICAL IMPLICATION: Probiotics may reduce the incidence of IgE-associated eczema in infancy.
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| 6. |
- Fagerås Böttcher, Malin, 1969-, et al.
(författare)
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Cytokine responses to allergens during the first 2 years of life in Estonian and Swedish children
- 2006
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894 .- 1365-2222. ; 36:5, s. 619-628
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Tidskriftsartikel (refereegranskat)abstract
- Background The prevalence of atopic disease among children in the formerly socialist countries in Europe, with a life style similar to that prevailing in Western Europe 30–40 years ago, is low, whereas there has been a pronounced increase in industrialized countries over the last decades. The environment during infancy influences the risk of developing allergy for many years, perhaps even for life.Objective To investigate the development of allergen-specific cytokine responses during the first 2 years of life in two geographically adjacent countries with marked differences in living conditions and incidence of atopic diseases, i.e. Estonia and Sweden.Methods The development of immune responses to food (β-lactoglobulin (BLG) and ovalbumin (OVA)) and inhalant (cat and birch) allergens was studied from birth up to the age of 2 years in 30 Estonian and 76 Swedish infants. Clinical investigation and skin prick tests were performed and blood samples were obtained at birth and at 3, 6, 12 and 24 months.Results The levels of IL-5, IL-10 and IL-13 secreted by peripheral blood mononuclear cells stimulated with BLG, OVA and cat allergen in Estonian and Swedish infants declined during the first 3 months of life. All cytokines then progressively increased in the Swedish infants, indicating the replacement of non-specifically responding immature cord blood T cells with specific T memory cells, which are primed postnatally. The resurgence of allergen-specific responses in the Estonian infants was less marked. These differences were particularly notable for birch-specific T cell responses, which correlated with development of atopic disease in the Swedish children.Conclusions The development of specific T cell memory to food and inhalant allergens during the first 2 years of life differs between infants living in Sweden and Estonia, and mirrors the disparate patterns of expression of allergic disease which subsequently develops in the respective populations.
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| 7. |
- Fagerås Böttcher, Malin, et al.
(författare)
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Low breast milk TGF-beta2 is induced by Lactobacillus reuteri supplementation and associates with reduced risk of sensitization during infancy
- 2008
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Ingår i: Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology. - : Wiley. - 1399-3038. ; 19:6, s. 497-504
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Tidskriftsartikel (refereegranskat)abstract
- The immunological composition of breast milk differs between mothers. The reasons for these differences and the consequences for the breast-fed infants are poorly understood. The aim of this study was to evaluate the effect of probiotic Lactobacillus reuteri supplementation on the immunological composition of breast milk in relation to sensitization and eczema in the babies. Total IgA, secretory IgA (SIgA), TGF-beta1, TGF-beta2, IL-10, TNF, soluble CD14 (sCD14), and Na/K ratios were analyzed in colostrum and mature milk obtained from women treated with L. reuteri (n = 54) or placebo (n = 55) from gestational week 36 until delivery. Bacteriological analyses of L. reuteri were performed in faecal samples of the mothers. The infants were followed prospectively for 2 yr regarding development of eczema and sensitization as defined by a positive skin prick test and/or circulating allergen-specific IgE antibodies at 6, 12, and 24 months of age. Supplementation of L. reuteri during pregnancy was associated with low levels of TGF-beta2 and slightly increased levels of IL-10 in colostrum. For TGF-beta2, this association was most pronounced in mothers with detectable L. reuteri in faeces. Infants receiving breast milk with low levels of TGF-beta2 were less likely to become sensitized during their first 2 yr of life. A similar trend was observed for development of IgE-associated eczema. The levels of total IgA, SIgA, TGF-beta1, TNF, sCD14, and Na/K ratios in breast milk were not affected by the intake of L. reuteri. None of these parameters correlated with sensitization or development of eczema in the infant, except for high Na/K ratios that associated with increased risk of sensitization. Supplementation with L. reuteri during late pregnancy reduces breast milk levels of TGF-beta2, and low levels of this cytokine are associated with less sensitization and possibly less IgE-associated eczema in breast-fed infants.
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| 9. |
- Sandin, Anna, et al.
(författare)
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Faecal short chain fatty acid pattern and allergy in early childhood
- 2009
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Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 98:5, s. 823-827
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To investigate whether functional changes of the gut flora over time were related to sensitization and allergic symptoms at four years of age.Methods: The levels of short chain fatty acids (SCFAs) in faecal samples at one (n = 139) and four (n = 53) years of age were related to the development of positive skin prick tests (SPT) and allergic symptoms during the first four years of life.Results: Faecal acetic (p < 0.01) and propionic (p < 0.01) acids decreased from one to four years of age, while valeric acid (p < 0.001) increased. Low levels of i-butyric (p = 0.01), i-valeric (p = 0.03) and valeric acids (p = 0.02) at one year were associated with questionnaire-reported symptoms of food allergy at four years. Positive SPTs and allergic symptoms at four years were associated with low faecal levels of i-butyric, i-valeric and valeric acids. At one year of age, infants with, as compared to without older siblings had higher median levels of valeric acid.Conclusion: A slow functional maturation of the gut microflora, as measured by faecal levels of SCFAs is associated with allergy both at one and four years. The findings lend further support to an association between allergy and the development of microbial diversity.
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| 10. |
- Sandin, Anna, et al.
(författare)
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Prevalence of self-reported food allergy and IgE antibodies to food allergens in Swedish and Estonian schoolchildren
- 2005
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Ingår i: European Journal of Clinical Nutrition. - : Springer Science and Business Media LLC. - 0954-3007 .- 1476-5640. ; 59:3, s. 399-403
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To compare the prevalence of self-reported food allergy and IgE antibodies to food allergens in wheezing and non-wheezing Estonian and Swedish schoolchildren, in the light of the disparities in the standard of living, food consumption and prevalence of respiratory allergies that still exist between Estonia and the Scandinavian countries. Design and setting: As a part of the ISAAC Phase II study, children from a random sample of schools in Tallinn in Estonia and Linköping and Östersund in Sweden participated in skin prick tests to inhalant allergens and the parents replied to questionnaires. IgE antibodies against a panel of food allergens (egg white, milk, soy bean, fish, wheat and peanut) were taken from children with questionnaire-reported wheezing and a random sample of nonwheezing children. Subjects: Children aged 10-11 y. Results: The prevalence of self-reported food allergy was similar in Estonia and Sweden and about twice as high in wheezing children than in nonwheezing children. In Estonia, however, 3% of the children with perceived food allergy reported reactions from at least four different foods, as compared to 31% in Sweden. The prevalence of sensitisation to food allergens was similar in wheezing and nonwheezing children in Estonia (8%) while, in Swedish children, IgE antibodies to food allergens were more likely among wheezing children (Linköping 38 vs 11%, crude OR 5.1, 95% CI 2.2-11.6, and Östersund 24 vs 7%, crude OR 4.1, 95% CI 1.9-8.5). Conclusion: Our study suggests that IgE-mediated food reactions were less likely in Estonian schoolchildren. Moreover, the perception of food allergy and thereby the meaning of self-reported food allergy appears to be different in the two countries. © 2005 Nature Publishing Group. All rights reserved.
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