| 1. |
- Adlerberth, Ingegerd, 1959, et al.
(författare)
-
Gut microbiota and development of atopic eczema in 3 European birth cohorts.
- 2007
-
Ingår i: The Journal of allergy and clinical immunology. - : Elsevier BV. - 0091-6749 .- 1097-6825. ; 120:2, s. 343-50
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Stimulation of the immune system by gut microbes might prevent allergy development. OBJECTIVE: The present study examined the hypothesis that sensitization to food allergens and atopic eczema are influenced by the infantile intestinal colonization pattern. METHODS: Infants were recruited perinatally in Göteborg (n = 116), London (n = 108), and Rome (n = 100). Commensal bacteria were identified to the genus or species level in rectal (3 days) and quantitative stool cultures (7, 14, and 28 days and 2, 6, and 12 months of age). At 18 months of age, atopic eczema and total and food-specific IgE levels were assessed. These outcomes were modeled in relation to time to colonization with 11 bacterial groups and to ratios of strict anaerobic to facultative anaerobic bacteria and gram-positive to gram-negative bacteria at certain time points. Study center, mode of delivery, parity, and infant diet were included as covariates. RESULTS: Neither atopic eczema nor food-specific IgE by 18 months of age were associated with time of acquisition of any particular bacterial group. Cesarean section delayed colonization by Escherichia coli and Bacteroides and Bifidobacterium species, giving way to, for example, Clostridium species. Lack of older siblings was associated with earlier colonization by Clostridium species and lower strict anaerobic/facultative anaerobic ratio at 12 months. CONCLUSIONS: This study does not support the hypothesis that sensitization to foods or atopic eczema in European infants in early life is associated with lack of any particular culturable intestinal commensal bacteria. CLINICAL IMPLICATIONS: The nature of the microbial stimulus required for protection from allergy remains to be identified.
|
|
| 2. |
- Adlerberth, Ingegerd, 1959, et al.
(författare)
-
Reduced enterobacterial and increased staphylococcal colonization of the infantile bowel: an effect of hygienic lifestyle?
- 2006
-
Ingår i: Pediatric research. - : Springer Science and Business Media LLC. - 0031-3998 .- 1530-0447. ; 59:1, s. 96-101
-
Tidskriftsartikel (refereegranskat)abstract
- The modern Western lifestyle may have altered the composition of the commensal microflora. Here, we investigated the first year's intestinal colonization pattern in 99 vaginally delivered Swedish infants and 17 delivered by cesarean section. Rectal swabs obtained at 3 d of age were cultured for aerobic bacteria and fecal samples obtained at 1, 2, 4, and 8 wk and at 6 and 12 mo of age were cultivated quantitatively for aerobic and anaerobic bacteria. Vaginally delivered infants more often had Escherichia coli compared with cesarean section-delivered infants, whereas the latter more frequently carried other enterobacteria, such as Klebsiella and Enterobacter. Independent of delivery mode, it took 2 mo until most infants were colonized by enterobacteria, traditionally the first colonizers. In contrast, coagulase-negative staphylococci colonized 99% of the infants from d 3 onwards. The poor adaptation of staphylococci to the gut was shown by declining population sizes after some weeks. Dominating anaerobes were initially bifidobacteria and clostridia, whereas Bacteroides initially colonized only 30% of vaginally delivered infants and increased very slowly in prevalence. Bacteroides colonization was delayed up to 1 y in cesarean section-delivered compared with vaginally delivered infants. Our results show that some "traditional" fecal bacteria are acquired late today especially in cesarean section-delivered infants, probably due to limited environmental circulation. In their absence, skin bacteria like staphylococci have become the first gut colonizers.
|
|
| 3. |
- Adlerberth, Ingegerd, 1959, et al.
(författare)
-
Toxin-producing Clostridium difficile strains as long-term gut colonizers of healthy infants.
- 2014
-
Ingår i: Journal of clinical microbiology. - 1098-660X. ; 52:1, s. 173-179
-
Tidskriftsartikel (refereegranskat)abstract
- Clostridium difficile is a colonizer of the human gut, and toxin-producing strains may cause diarrhea if infectious burden is heavy. Infants are more frequently colonized than adults, but rarely develop C. difficile disease. It is not known whether strains of C. difficile differ in capacity to colonize and persist in the human gut microbiota. Here, we strain-typed isolates of C. difficile colonizing 42 healthy infants followed from birth to ≥12 months of age, using PCR ribotyping of the 16S-23S rRNA intergenic spacer region. The isolates were also characterized regarding carriage of the toxin genes tcdA, tcdB and cdtA/B, and capacity to produce toxin B in vitro. Most strains (71%) were toxin-producers, and 51% belonged to the 001 or 014 ribotypes, that often cause disease in adults. These ribotypes were significantly more likely than other ones to persist for ≥6 months in the infant micobiota, and were isolated from 13/15 children carrying such long-term colonizing strains. Ribotype 001 strains were often acquired in the first week of life and attained higher population counts than other C. difficile ribotypes in newborn infants' faeces. Several toxin-negative ribotypes were identified, two of which (GI and GIII) were long-term colonizers, each in one infant. Our results suggest that the toxin-producing C. difficile ribotypes 001 and 014 have special fitness in the infantile gut microbiota. Toxin-producing strains colonizing young children for long time periods may represent a reservoir for strains causing disease in adults.
|
|
| 4. |
- Ahrné, Siv, et al.
(författare)
-
Lactobacilli in the intestinal microbiota of Swedish infants
- 2005
-
Ingår i: Microbes and Infection. - : Elsevier BV. - 1286-4579 .- 1769-714X. ; 7:11-12, s. 1256-62
-
Tidskriftsartikel (refereegranskat)abstract
- Lactobacillus colonisation was examined in 112 Swedish infants. Faecal samples obtained at 1, 2, 4 and 8 weeks and at 6, 12 and 18 months of age were cultivated quantitatively on Rogosa agar. Lactobacilli were speciated by PCR and typed to the strain level by randomly amplified polymorphic DNA (RAPD). Lactobacilli reached a peak at 6 months when 45% of the infants were colonised. L. rhamnosus and L. gasseri were the most common species in this period. Colonisation by lactobacilli in general (P < 0.01) and L. rhamnosus in particular (P < 0.05) was more common in breast-fed than in weaned infants at 6 months of age. Lactobacillus isolation reached a nadir of 17% by 12 months (P < 0.0001), but increased to 31% by 18 months of age P < 0.05). The food-related species L. paracasei, L. plantarum, L. acidophilus and L. delbrueckii dominated in this second phase. A single strain persisted for at least 3 weeks in 17% of the infants during the first 6 months, most commonly L. rhamnosus. Lactobacillus population counts in colonised infants increased from 10(6.4) cfu/g at 1 week to 10(8.8) cfu/g at 6 months, and then dropped to 10(5.4) cfu/g faeces at 12 months of age. Lactobacillus colonisation was not significantly related to delivery mode, or to presence of siblings or pets in the household. Our results suggest that certain Lactobacillus species, especially L. rhamnosus, thrive in the intestinal flora of breast-fed infants. After weaning they are replaced by other Lactobacillus species of types found in food.
|
|
| 5. |
- Barman, Malin, 1983, et al.
(författare)
-
Cord Blood Levels of EPA, a Marker of Fish Intake, Correlate with Infants' T- and B-Lymphocyte Phenotypes and Risk for Allergic Disease
- 2020
-
Ingår i: Nutrients. - : MDPI AG. - 2072-6643 .- 2072-6643. ; 12:10, s. 1-18
-
Tidskriftsartikel (refereegranskat)abstract
- Maternal fish intake during pregnancy has been associated with reduced allergy development in the offspring and here, we hypothesized that components of fish stimulate fetal immune maturation. The aim of this study was to investigate how maternal fish intake during pregnancy and levels of n-3 long-chain polyunsaturated fatty acids (LCPUFAs) in the infant's cord serum correlated with different subsets of B- and T-cells in cord blood and B-cell activating factor (BAFF) in cord plasma, and with doctor-diagnosed allergy at 3 and 8 years of age in the FARMFLORA birth-cohort consisting of 65 families. Principal component analysis showed that infant allergies at 3 or 8 years of age were negatively associated with the proportions of n-3 LCPUFAs (eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) in infant cord serum, which, in turn correlated positively with maternal fish intake during pregnancy. Both maternal fish intake and cord serum n-3 LCPUFAs correlated negatively to CD5(+) B cells and the FOXP3(+)CD25(high) of the CD4(+) T cell subsets in cord blood, but not to BAFF in cord plasma. Our observational study suggests that fish might contain components that promote maturation of the infant's immune system in a manner that protects against allergy development.
|
|
| 6. |
- Barman, Malin, 1983, et al.
(författare)
-
High Levels of Both n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids in Cord Serum Phospholipids Predict Allergy Development
- 2013
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:7
-
Tidskriftsartikel (refereegranskat)abstract
- Background Long-chain polyunsaturated fatty acids (LCPUFAs) reduce T-cell activation and dampen inflammation. They might thereby counteract the neonatal immune activation and hamper normal tolerance development to harmless environmental antigens. We investigated whether fatty acid composition of cord serum phospholipids affects allergy development up to age 13 years. Methods From a population-based birth-cohort born in 1996/7 and followed until 13 years of age (n = 794), we selected cases with atopic eczema (n = 37) or respiratory allergy (n = 44), as well as non-allergic non-sensitized controls (n = 48) based on diagnosis at 13 years of age. Cord and maternal sera obtained at delivery from cases and controls were analysed for proportions of saturated, monounsaturated and polyunsaturated fatty acids among serum phospholipids. Results The cord serum phospholipids from subject who later developed either respiratory allergy or atopic eczema had significantly higher proportions of 5/8 LCPUFA species, as well as total n-3 LCPUFA, total n-6 LCPUFA and total LCPUFA compared to cord serum phospholipids from controls who did not develop allergy (P<0.001 for all comparisons). Conversely, individuals later developing allergy had lower proportion of the monounsaturated fatty acid 18:1n-9 as well as total MUFA (p<0.001) among cord serum phospholipids. The risk of respiratory allergy at age 13 increased linearly with the proportion of n-3 LCPUFA (Ptrend<0.001), n-6 LCPUFA (Ptrend = 0.001), and total LCPUFA (Ptrend<0.001) and decreased linearly with the proportions of total MUFA (Ptrend = 0.025) in cord serum phospholipids. Furthermore, Kaplan-Meier estimates of allergy development demonstrated that total LCPUFA proportion in cord serum phospholipids was significantly associated with respiratory allergy (P = 0.008) and sensitization (P = 0.002), after control for sex and parental allergy. Conclusion A high proportion of long-chain PUFAs among cord serum phospholipids may predispose to allergy development. The mechanism is unknown, but may involve dampening of the physiologic immune activation in infancy needed for proper maturation of the infant's immune system.
|
|
| 7. |
- Barman, Malin, 1983, et al.
(författare)
-
No association between allergy and current 25-hydroxy vitamin D in serum or vitamin D intake
- 2015
-
Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 104:4, s. 405-413
-
Tidskriftsartikel (refereegranskat)abstract
- Aim Vitamin D may be involved in allergy development, but there is conflicting evidence. We investigated if dietary intake of vitamin D and levels of 25OHD in serum differed between allergic and nonallergic adolescents and if serum 25OHD correlated with dietary intake of vitamin D or season of blood sampling. Methods Serum 25-hydroxy vitamin D (25OHD) levels were analysed in 13-year-old subjects with atopic eczema (n = 55), respiratory allergy (n = 55) or no allergy (n = 55). Intake of fat-containing foods was assessed by food-frequency questionnaires, and total daily vitamin D intake was calculated. Logistic regression was used to adjust for gender, parental allergy and time of blood sampling. Results Subjects with atopic eczema or respiratory allergy did not differ from nonallergic controls regarding serum 25OHD levels or calculated vitamin D intake. Subjects sampled in the autumn had significantly higher levels of serum 25OHD than subjects sampled in the winter or spring. Serum 25OHD levels correlated to consumption of vitamin D-fortified lean milk (p = 0.001). Conclusion The findings suggest no association between allergy and 25OHD levels in serum or vitamin D intake in adolescents. Serum 25OHD levels correlated to intake of vitamin D-fortified lean milk.
|
|
| 8. |
- Barman, Malin, 1983, et al.
(författare)
-
Nutritional impact on Immunological maturation during Childhood in relation to the Environment (NICE): a prospective birth cohort in northern Sweden
- 2018
-
Ingår i: BMJ Open. - : BMJ. - 2044-6055 .- 2044-6055. ; 8:10
-
Tidskriftsartikel (refereegranskat)abstract
- © Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. INTRODUCTION: Prenatal and neonatal environmental factors, such as nutrition, microbes and toxicants, may affect health throughout life. Many diseases, such as allergy and impaired child development, may be programmed already in utero or during early infancy. Birth cohorts are important tools to study associations between early life exposure and disease risk. Here, we describe the study protocol of the prospective birth cohort, 'Nutritional impact on Immunological maturation during Childhood in relation to the Environment' (NICE). The primary aim of the NICE cohort is to clarify the effect of key environmental exposures-diet, microbes and environmental toxicants-during pregnancy and early childhood, on the maturation of the infant's immune system, including initiation of sensitisation and allergy as well as some secondary outcomes: infant growth, obesity, neurological development and oral health.METHODS AND ANALYSIS: The NICE cohort will recruit about 650 families during mid-pregnancy. The principal inclusion criterion will be planned birth at the Sunderby Hospital in the north of Sweden, during 2015-2018. Questionnaires data and biological samples will be collected at 10 time-points, from pregnancy until the children reach 4 years of age. Samples will be collected primarily from mothers and children, and from fathers. Biological samples include blood, urine, placenta, breast milk, meconium, faeces, saliva and hair. Information regarding allergic heredity, diet, socioeconomic status, lifestyle including smoking, siblings, pet ownership, etc will be collected using questionnaires. Sensitisation to common allergens will be assessed by skin prick testing and allergic disease will be diagnosed by a paediatrician at 1 and 4 years of age. At 4 years of age, the children will also be examined regarding growth, neurobehavioural and neurophysiological status and oral health.ETHICS AND DISSEMINATION: The NICE cohort has been approved by the Regional Ethical Review Board in Umeå, Sweden (2013/18-31M). Results will be disseminated through peer-reviewed journals and communicated on scientific conferences.
|
|
| 9. |
- Gio-Batta, Monica, et al.
(författare)
-
Fecal short chain fatty acids in children living on farms and a link between valeric acid and protection from eczema.
- 2020
-
Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- Children growing up on farms have low rates of allergy, but the mechanism for this protective effect has not been fully elucidated. Short chain fatty acids (SCFAs) produced by the gut microbiota may play a role in protection from allergy. We measured fecal SCFA levels in samples collected from 28 farming and 37 control children over the first 3 years of life using gas chromatography. Data on diet and other host factors were recorded and allergy was diagnosed at 8 years of age. Among all children, median propionic and butyric acid concentration increased over the first 3 years, and longer SCFAs typically appeared by 1 year of age. Farm children had higher levels of iso-butyric, iso-valeric and valeric acid at 3 years of age than rural controls. In addition, children with elder siblings had higher levels of valeric acid at 3 years of age, and dietary factors also affected SCFA pattern. High levels of valeric acid at 3 years of age were associated with low rate of eczema at 8 years of age. The fecal SCFA pattern in farm children suggests a more rapid maturation of the gut microbiota. Valeric acid or associated microbes may have protective potential against eczema.
|
|
| 10. |
- Hesselmar, Bill, 1955, et al.
(författare)
-
An index to predict asthma in wheezing young children produced promising initial results.
- 2017
-
Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253. ; 106:9, s. 1532-1533
-
Tidskriftsartikel (refereegranskat)abstract
- Diagnosing asthma is difficult in infants and preschool children because wheezing is common in this age group and it is not synonymous with asthma. Some children outgrow the tendency to wheeze during colds in a few years' time, whereas other develop asthma. Efforts have been made to find ways to identify the subgroup of preschool children with wheeze who are most likely to develop asthma (1,2). However, the different asthma predictive indexes mainly aim to predict children who will have a persistent wheeze or asthma, not necessarily the subgroup who will outgrow their symptoms. This article is protected by copyright. All rights reserved.
|
|
