title: Effects of prebiotics on the immune response to vaccination in the elderly.
abstract: BACKGROUND
  Prebiotics stimulate the growth of bifidogenic bacteria in the gut. The aim of this work was to assess the effects of a prebiotic mixture on the immune response in healthy elderly people.
  
  
  METHODS
  Healthy free-living elderly people (age, > or = 70 years), receiving a nutritional supplement that provided 1.6 MJ, 15 g of protein, and 50% of vitamin daily reference values per day, were randomly assigned to receive a prebiotic mixture (6 g/d of a 70% raftilose and 30% raftiline mixture) or placebo (6 g of maltodextrin powder) for 28 weeks. At week 2 of the study, all subjects were vaccinated with influenza and pneumococcal vaccines. At weeks 0, 2, and 8 of the study, serum total proteins, albumin, immunoglobulins, saliva secretory immunoglobulin A (IgA), and serum titers of influenza A and B and pneumococcal antibodies were measured. At week 8, cultured peripheral monocyte cell secretion of interleukin-4, interferon-gamma, and lymphocyte proliferation, stimulated with phytohemagglutinin and influenza antigen, were measured.
  
  
  RESULTS
  Sixty-six subjects were considered eligible for the study, and 43 (20 receiving prebiotics and 23 receiving placebo) were considered for final analyses on a per protocol basis. No changes in serum proteins, albumin, immunoglobulins, and secretory IgA were observed. Antibodies against influenza B and pneumococcus increased significantly from weeks 0 to 8, with no significant differences between groups. Antibodies against influenza A did not increase. No effects of prebiotics on interleukin-4 and interferon-gamma secretion by cultured monocytes were observed.
  
  
  CONCLUSIONS
  No immunological effects of prebiotics were observed in this study.
authors.affiliation: Institute of Nutrition and Food Technology, Faculty of Medicine, University of Chile, Santiago. dbunout@uec.inta.uchile.cl
authors.forename: Daniel
authors.initials: D
authors.lastname: Bunout
authors.forename: Sandra
authors.initials: S
authors.lastname: Hirsch
authors.forename: María
authors.initials: M
authors.lastname: Pía de la Maza
authors.forename: Carlos
authors.initials: C
authors.lastname: Muñoz
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Haschke
authors.forename: Philippe
authors.initials: P
authors.lastname: Steenhout
authors.forename: Petra
authors.initials: P
authors.lastname: Klassen
authors.forename: Gladys
authors.initials: G
authors.lastname: Barrera
authors.forename: Vivien
authors.initials: V
authors.lastname: Gattas
authors.forename: Margarita
authors.initials: M
authors.lastname: Petermann
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000917:Antibody Formation / Q000276:immunology*; D001798:Blood Proteins / Q000276:immunology; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D022242:Pneumococcal Vaccines / Q000276:immunology*; D019936:Probiotics / Q000008:administration & dosage*; D012016:Reference Values; D013997:Time Factors; D014611:Vaccination
chemical_list: D001798:Blood Proteins; D016207:Cytokines; D007136:Immunoglobulins; D007252:Influenza Vaccines; D022242:Pneumococcal Vaccines