title: Exposures influencing total IgA level in colostrum.
abstract: Immunoglobulin A (IgA) is a predominant immunoglobulin present in human breast milk and is known to play an important role in infant gut immunity maturation. Breast milk composition varies between populations, but the environmental and maternal factors responsible for these variations are still unclear. We examined the relationship between different exposures and levels of IgA in colostrum. The objective of this study was to examine whether exposures analysed influence levels of IgA in colostrum. The present study used 294 colostrum samples from the MecMilk International cohort, collected from women residing in London, Moscow and Verona. Samples were analysed in automated Abbott Architect Analyser. We found an inverse correlation between time postpartum and colostrum total IgA level (r=-0.49, P<0.001). Adjusting for maternal parity, smoking, fresh fruit and fish consumption and allergen sensitization, multiple regression model showed that IgA levels were influenced by colostrum collection time (P<0.0001) and country of collection (P<0.01). Mode of delivery influence did not appear to be significant in univariate comparisons, once adjusted for the above maternal characteristics it showed a significant influence on total IgA (P=0.01). We conclude that the concentration of IgA in colostrum drops rapidly after birth and future studies should always consider this factor in analysis. IgA concentration varied significantly between countries, with the highest level detected in Moscow and lowest in Verona. Mode of delivery effect should be confirmed on larger cohorts. Further work is needed to determine ways to correct for IgA decline over time in colostrum, and to find the cause of variations in IgA levels between the countries.
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: D
authors.initials: D
authors.lastname: Munblit
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: S
authors.initials: S
authors.lastname: Sheth
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: P
authors.initials: P
authors.lastname: Abrol
authors.affiliation: 2International Inflammation (in-FLAME) Network of the World Universities Network.
authors.forename: M
authors.initials: M
authors.lastname: Treneva
authors.affiliation: 2International Inflammation (in-FLAME) Network of the World Universities Network.
authors.forename: D G
authors.initials: DG
authors.lastname: Peroni
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: L-Y
authors.initials: LY
authors.lastname: Chow
authors.affiliation: 5Department of Life and Reproduction Sciences,Section of Paediatrics,University of Verona,Italy.
authors.forename: A L
authors.initials: AL
authors.lastname: Boner
authors.affiliation: 2International Inflammation (in-FLAME) Network of the World Universities Network.
authors.forename: A
authors.initials: A
authors.lastname: Pampura
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: J O
authors.initials: JO
authors.lastname: Warner
authors.affiliation: 1Department of Paediatrics,Imperial College London,London,UK.
authors.forename: R J
authors.initials: RJ
authors.lastname: Boyle
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003126:Colostrum / Q000737:chemistry / Q000276:immunology*; D004032:Diet; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007070:Immunoglobulin A / Q000032:analysis*; D007743:Labor, Obstetric / Q000276:immunology; D010298:Parity / Q000276:immunology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000276:immunology*; D012907:Smoking
chemical_list: D007070:Immunoglobulin A
keywords: breast milk; colostrum; environmental factors; maternal factors; total IgA