title: The impact of vitamin A supplementation on the immune system of vitamin A-deficient children.
abstract: OBJECTIVE
  To investigate the effect of vitamin A supplementation on parameters of the immune system of vitamin A-deficient children.
  
  
  METHODS
  The study was carried out in four phases: 1) determination of serum retinol in 631 children from 36 to 83 months of age; 2) assessment of immunological markers [immunoglobulins and complement fractions, immunophenotyping of T and B lymphocytes, and natural killer (NK) cells], blood count, and serum ferritin of 52 vitamin A-deficient children (serum retinol < 0.70 micromol/L); 3) supplementation of the 52 deficient children with 200,000 IU of vitamin A; 4) determination of serum retinol and the immunological parameters 2 months after vitamin A supplementation.
  
  
  RESULTS
  before vitamin A supplementation, 24.0 % of the children were anemic and 4.3 %had reduced ferritin concentrations. There was no significant difference between mean values of retinol according to the presence/absence of anemia. The mean values of the humoral and cellular immunological parameters did not show a statistically significant difference before and after supplementation with vitamin A. Children with concomitant hypovitaminosis A and anemia presented a significant increase in absolute CD4 and CD8 T-cell counts after vitamin A supplementation (p < 0.05).
  
  
  CONCLUSIONS
  vitamin A had an effect on the recruitment of T and B lymphocytes to the circulation of children with hypovitaminosis A and anemia.
authors.affiliation: Department of Nutrition, Federal University of Teresina, Piaui, Brazil. aapaiva@yahoo.com.br
authors.forename: Adriana
authors.initials: A
authors.lastname: de Azevedo Paiva
authors.forename: Patricia Helen
authors.initials: PH
authors.lastname: Rondó
authors.forename: Lourdes
authors.initials: L
authors.lastname: Rehder Vaz-de-Lima
authors.forename: Carmem
authors.initials: C
authors.lastname: de Freitas Oliveira
authors.forename: Mirthes
authors.initials: M
authors.lastname: Ueda
authors.forename: Cecilia
authors.initials: C
authors.lastname: Gonçalves-Carvalho
authors.forename: Luis Gustavo
authors.initials: LG
authors.lastname: Reinaldo
mesh_terms: D000740:Anemia / Q000453:epidemiology / Q000276:immunology; D018798:Anemia, Iron-Deficiency / Q000453:epidemiology / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D001772:Blood Cell Count; D001938:Brazil / Q000453:epidemiology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007107:Immune System / Q000187:drug effects*; D008297:Male; D010352:Patient Dropouts; D015995:Prevalence; D014801:Vitamin A / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D014802:Vitamin A Deficiency / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology*
chemical_list: D015415:Biomarkers; D014801:Vitamin A; D005293:Ferritins