title: Vitamin B6 and the immunity in kidney transplant recipients.
abstract: OBJECTIVE
  The study aimed to determine vitamin B6 status in elderly (age ≥ 60 years) and younger (age <60 years) recipients of allogeneic kidney graft and to investigate associations between vitamin B6 status and immunity markers.
  
  
  METHODS
  A retrospective observational study.
  
  
  METHODS
  The study was conducted at the Medical University of Gdańsk, Poland.
  
  
  METHODS
  We recruited 34 kidney allograft recipients (17 males and 17 females) and allocated them into 2 groups: patients aged ≥ 60 years (18 patients) and those aged <60 years (16 patients). Exclusion criteria included patients receiving vitamin B6 supplementation or drugs known to influence vitamin B6 metabolism.
  
  
  METHODS
  Plasma levels of pyridoxal 5'-phosphate (PLP), pyridoxal, pyridoxine, pyridoxamine, pyridoxamine 5'-phosphate, and 4 pyridoxic acid were determined by high-performance liquid chromatography. Measured immunity markers were serum cytokines (interleukin-6, interleukin-10, and transforming growth factor-β), levels of T-lymphocyte subsets, and the proliferative ability of peripheral blood mononuclear cells.
  
  
  RESULTS
  Concentrations of all vitamin B6 vitamers in plasma (PLP, pyridoxal, pyridoxamine 5'-phosphate, pyridoxamine, pyridoxine, 4 pyridoxic acid) were comparable in the 2 studied groups. There were no cases of PLP deficiency in the study population, but 29% of patients had PLP concentrations more than the upper reference limit. Vitamin B6 vitamer concentrations were not influenced by gender, estimated glomerular filtration rate, and circulating phosphate concentration. There was no difference in immunity markers according to age. However, the plasma concentrations of vitamin B6 vitamers were inversely associated with levels of CD28(+) lymphocyte subsets, as well as with the proliferative response of peripheral blood mononuclear cells in both groups.
  
  
  CONCLUSIONS
  No cases of vitamin B6 deficiency were found among kidney allograft recipients, and we report inverse links between vitamin B6 vitamer concentrations and markers of cellular immunity, suggesting that bioactive vitamin B6 concentration in kidney allograft recipients merits further investigation.
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Medical University of Gdańsk, Gdańsk, Poland. maja@gumed.edu.pl
authors.forename: Magdalena
authors.initials: M
authors.lastname: Jankowska
authors.forename: Marcin
authors.initials: M
authors.lastname: Marszałł
authors.forename: Alicja
authors.initials: A
authors.lastname: Dębska-Ślizień
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Carrero
authors.forename: Bengt
authors.initials: B
authors.lastname: Lindholm
authors.forename: Wojciech
authors.initials: W
authors.lastname: Czarnowski
authors.forename: Bolesław
authors.initials: B
authors.lastname: Rutkowski
authors.forename: Piotr
authors.initials: P
authors.lastname: Trzonkowski
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D002648:Child; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D007109:Immunity / Q000276:immunology*; D016753:Interleukin-10 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D016030:Kidney Transplantation; D053779:Latent TGF-beta Binding Proteins / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011730:Pyridoxal / Q000097:blood; D011733:Pyridoxamine / Q000097:blood; D011735:Pyridoxic Acid / Q000097:blood; D011736:Pyridoxine / Q000097:blood; D012189:Retrospective Studies; D016176:T-Lymphocyte Subsets / Q000378:metabolism; D025101:Vitamin B 6 / Q000097:blood*; D026681:Vitamin B 6 Deficiency / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D053779:Latent TGF-beta Binding Proteins; C509034:Ltbp1 protein, rat; D016753:Interleukin-10; D011730:Pyridoxal; D011735:Pyridoxic Acid; D011733:Pyridoxamine; D025101:Vitamin B 6; D011736:Pyridoxine