title: Maternal weight and excessive weight gain during pregnancy modify the immunomodulatory potential of breast milk.
abstract: BACKGROUND
  Breast milk is an optimal source of nutrition for infants. It contains bioactive components including bacteria that support the microbial colonization and immune system development of the infant. The determinants of human milk composition remain poorly understood, although maternal nutritional and immunological status as well as lifestyle and dietary habits seem to have an impact.
  
  
  METHODS
  The subjects selected were women from a prospective follow-up study categorized by BMI. Milk samples were taken after delivery and at 1 and 6 mo later for analysis of composition in regard to transforming growth factor (TGF)-β2, soluble CD14 (sCD14), cytokines, and microbiota.
  
  
  RESULTS
  TGF-β2 and sCD14 levels in the breast milk of overweight mothers tended to be lower than the levels in that of normal-weight mothers. Also, higher levels of Staphylococcus group bacteria and lower levels of Bifidobacterium group bacteria were detected in overweight mothers as compared with normal-weight ones. The prevalence of Akkermansia muciniphila-type bacteria was also higher in overweight mothers, and the numbers of these bacteria were related to the interleukin (IL)-6 concentration in the colostrum, which was in turn related to lower counts of Bifidobacterium group bacteria in the breast milk of overweight women.
  
  
  CONCLUSIONS
  Complex interactions of cytokines and microbiota in breast milk guide the microbiological, immunological, and metabolic programming of infant health. Our data may indicate the presence of an additional mechanism that may explain the heightened risk of obesity for infants of overweight and excessive weight gain mothers.
authors.affiliation: Department of Biotechnology, Institute of Agrochemistry and Food Science, Spanish National Research Council (IATA-CSIC), Valencia, Spain. mcolam@iata.csic.es
authors.forename: Maria Carmen
authors.initials: MC
authors.lastname: Collado
authors.forename: Kirsi
authors.initials: K
authors.lastname: Laitinen
authors.forename: Seppo
authors.initials: S
authors.lastname: Salminen
authors.forename: Erika
authors.initials: E
authors.lastname: Isolauri
mesh_terms: D016207:Cytokines / Q000032:analysis; D005260:Female; D006801:Humans; D056747:Immunomodulation / Q000276:immunology*; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D039382:Maternal Nutritional Physiological Phenomena / Q000276:immunology / Q000502:physiology*; D054892:Metagenome / Q000235:genetics; D008895:Milk, Human / Q000737:chemistry / Q000276:immunology* / Q000382:microbiology; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D053781:Transforming Growth Factor beta2 / Q000032:analysis; D015430:Weight Gain / Q000502:physiology*
chemical_list: D016207:Cytokines; D018950:Lipopolysaccharide Receptors; D053781:Transforming Growth Factor beta2