title: Altered mitochondrial response to activation of T-cells in neonate.
abstract: Mitochondrial functions have a major impact on T-cell functionality. In this study we characterized whether mitochondrial function in the neonatal T-cells differs from that in the adult T-cells during short T-cell activation.
  
  
  METHODS
  We used flow cytometry methods to test mitochondrial mass and to monitor mitochondrial Ca²⁺ levels, mitochondrial potential and superoxide generation in parallel with cytoplasmic Ca²⁺ levels during phythohaemagglutinine-induced activation of CD4+ and CD8+ T-cells of 12 term neonates and 11 healthy adults.
  
  
  RESULTS
  Baseline mitochondrial mass of CD4+ and CD8+ cells was lower in the neonate than in the adult. In comparison with the adult, neonatal resting CD4+ T-cells had lower cytoplasmic Ca²⁺ levels and this was associated with normal activation induced Ca²⁺-response. During short-term activation cytoplasmic Ca²⁺-response was lower in neonatal than in adult CD8+ T-cells. Mitochondrial Ca²⁺ uptake was increased in CD4+ neonatal T cells while it decreased in CD8+ T-cells. Mitochondrial depolarization was increased in CD4+ and decreased in CD8+ neonatal T-cells compared to adults. Superoxide generation was higher and equal in neonatal CD4+ and CD8+ cells, respectively, compared to the adult ones.
  
  
  CONCLUSIONS
  Our data suggest that neonatal T-cells exhibit marked differences in mitochondrial function and superoxide generation compared to adult T-cells.
authors.affiliation: MTA-SE, Pediatrics and Nephrology Research Group, Hungarian Academy of Sciences, Semmelweis University , Budapest , Hungary.
authors.forename: G
authors.initials: G
authors.lastname: Mészáros
authors.forename: Cs
authors.initials: C
authors.lastname: Orbán
authors.forename: A
authors.initials: A
authors.lastname: Kaposi
authors.forename: G
authors.initials: G
authors.lastname: Toldi
authors.forename: B
authors.initials: B
authors.lastname: Gyarmati
authors.forename: T
authors.initials: T
authors.lastname: Tulassay
authors.forename: Barna
authors.initials: B
authors.lastname: Vásárhelyi
mesh_terms: D056704:Adaptive Immunity; D000328:Adult; D000367:Age Factors; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008928:Mitochondria / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D010641:Phenotype; D010835:Phytohemagglutinins / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D055815:Young Adult
chemical_list: D010835:Phytohemagglutinins; D013481:Superoxides; D002118:Calcium
keywords: T-cell; calcium; flow cytometry; mitochondrial membrane potential; neonate; superoxide