title: Aging-associated increase in indoleamine 2,3-dioxygenase (IDO) activity appears to be unrelated to the transcription of the IDO1 or IDO2 genes in peripheral blood mononuclear cells.
abstract: BACKGROUND
  Old age is associated with increased levels of circulating pro-inflammatory cytokines, a phenomenon termed inflamm-aging. Elevated levels of pro-inflammatory cytokines have been associated with several age-associated diseases and with a shortened lifespan. Indoleamine 2,3-dioxygenase (IDO) has immunomodulatory properties and its activity is elevated in inflammation, autoimmune disorders and malignancies. We have previously shown that IDO activity is increased in nonagenarians compared to young individuals and that high IDO activity is associated with mortality at old age.
  
  
  RESULTS
  In this study our aim was to assess whether this difference in IDO activity in the plasma was due to the differential expression of either the IDO1 or IDO2 gene in peripheral blood mononuclear cells. Our results show that IDO1 and IDO2 are not differently expressed in nonagenarians compared to controls and that the expression of IDO genes is not associated with the level of IDO activity in the plasma.
  
  
  CONCLUSIONS
  The level of IDO activity in the plasma is not regulated through the expression of IDO1 or IDO2 in the peripheral blood mononuclear cells.
authors: Department of Microbiology and Immunology, The School of Medicine, University of Tampere, Finland. saara.marttila@uta.fi.
authors: Saara
authors: S
authors: Marttila
authors: Juulia
authors: J
authors: Jylhävä
authors: Carita
authors: C
authors: Eklund
authors: Antti
authors: A
authors: Hervonen
authors: Marja
authors: M
authors: Jylhä
authors: Mikko
authors: M
authors: Hurme