title: Immune function in rural Gambian children is not related to season of birth, birth size, or maternal supplementation status.
abstract: BACKGROUND
  We previously showed that mortality from infectious diseases among young adults in rural Gambia is strongly correlated with the season of their birth. This suggests that early life insults that involve fetal malnutrition, exposure to natural toxins, or highly seasonal infections affecting the infant or pregnant mother cause permanent damage to the immune system. Excess mortality begins after puberty and has a maximal odds ratio of >10 for deaths between ages 25 and 50 y.
  
  
  OBJECTIVE
  We investigated the immune function of children according to birth weight, season of birth, and exposure to maternal dietary supplementation during pregnancy.
  
  
  METHODS
  Immune function was measured in 472 prepubertal children aged 6.5-9.5 y from 28 villages in rural Gambia. The mothers of these children had been randomly assigned to a high-energy prenatal supplementation program, which significantly increased birth weight. This permitted supplementation status, birth weight, and season of birth to be investigated as exposure variables. The outcome variables tested were naive responses to rabies and pneumococcus vaccines, delayed-type hypersensitivity skin reactions, and mucosal defense (secretory immunoglobulin A and dual-sugar permeability).
  
  
  RESULTS
  Immune responses were strongly related to current age and sex, suggesting a high level of sensitivity, but were not consistently related to birth weight, season of birth, or maternal supplementation (control compared with intervention).
  
  
  CONCLUSIONS
  Events in early life did not predict a measurable defect in immune response within this cohort of rural Gambian children. It is possible that the early programming of immune function may be mediated through a defect in immunologic memory or early senescence rather than through impairment of early responses.
authors.affiliation: International Nutrition Group, London School of Hygiene and Tropical Medicine, UK. sophie.moore@lshtm.ac.uk
authors.forename: S E
authors.initials: SE
authors.lastname: Moore
authors.forename: A C
authors.initials: AC
authors.lastname: Collinson
authors.forename: A M
authors.initials: AM
authors.lastname: Prentice
mesh_terms: D000328:Adult; D001724:Birth Weight; D002423:Cause of Death; D002648:Child; D015331:Cohort Studies; D003140:Communicable Disease Control; D019587:Dietary Supplements; D005260:Female; D005714:Gambia; D006304:Health Status; D006801:Humans; D007107:Immune System / Q000502:physiology*; D008137:Longitudinal Studies; D008297:Male; D008429:Maternal Welfare; D009752:Nutritional Status; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012423:Rural Health; D012621:Seasons; D014612:Vaccines / Q000276:immunology*
chemical_list: D014612:Vaccines