title: Low birth weight is associated with altered immune function in rural Bangladeshi children: a birth cohort study.
abstract: BACKGROUND
  Low birth weight is generally an outcome of a fetal insult or nutritional insufficiency. Recent studies have shown that such exposure early in life may have long-term implications for later immunocompetence and susceptibility to infectious diseases.
  
  
  OBJECTIVE
  We aimed to investigate the effect of birth weight on immune function in preschool-age children.
  
  
  METHODS
  A birth cohort cross-sectional study was conducted in children (n = 132) aged 60.8 +/- 0.32 mo who were born in Matlab, a rural area of Bangladesh, and whose weight and length were measured within 72 h of birth. The outcome measures were thymopoiesis, T cell turnover, acute phase response, and percentage of lymphocytes.
  
  
  RESULTS
  Children born with low birth weight (<2500 g; LBW group, n = 66) had significantly higher concentrations of T cell receptor excision circles in peripheral blood mononuclear cells-a biomarker for thymopoiesis-and significantly higher serum bactericidal activity and C-reactive protein concentrations than did children born with normal birth weight (>or=2500 g; NBW group, n = 66) (P < 0.05 for both). The LBW group children had significantly lower concentrations of interleukin 7 in plasma (P = 0.02), shorter telomere length in peripheral blood mononuclear cells (P = 0.02), and a lower percentage of CD3 T cells (P = 0.06) than did the NBW group children.
  
  
  CONCLUSIONS
  Greater peripheral T cell turnover (shorter telomeres and lower CD3 concentrations) due to immune activation (elevated C-reactive protein concentrations and bactericidal activity) may have resulted in a greater need for replenishment from the thymus (higher T cell receptor excision circles); these events may cause lower immune functional reserve in preschool-age children born with LBW. Thus, LBW has implications for immunocompetence and increased vulnerability to infectious diseases in later life.
authors.affiliation: International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh. rubhana@icddrb.org
authors.forename: Rubhana
authors.initials: R
authors.lastname: Raqib
authors.forename: Dewan S
authors.initials: DS
authors.lastname: Alam
authors.forename: Protim
authors.initials: P
authors.lastname: Sarker
authors.forename: Shaikh Meshbahuddin
authors.initials: SM
authors.lastname: Ahmad
authors.forename: Gul
authors.initials: G
authors.lastname: Ara
authors.forename: Mohammed
authors.initials: M
authors.lastname: Yunus
authors.forename: Sophie E
authors.initials: SE
authors.lastname: Moore
authors.forename: George
authors.initials: G
authors.lastname: Fuchs
mesh_terms: D000911:Antibodies, Monoclonal / Q000097:blood; D001459:Bangladesh; D001724:Birth Weight; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D006801:Humans; D007109:Immunity; D016130:Immunophenotyping; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008213:Lymphocyte Activation; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D012016:Reference Values; D012424:Rural Population
chemical_list: D000911:Antibodies, Monoclonal; D011948:Receptors, Antigen, T-Cell; D002097:C-Reactive Protein