title: PBMCs reflect the immune component of the WAT transcriptome--implications as biomarkers of metabolic health in the postprandial state.
abstract: METHODS
  Food and nutrition studies often require accessing metabolically active tissues, including adipose tissue. This can involve invasive biopsy procedures that can be a limiting factor in study design. In contrast, peripheral blood mononuclear cells (PBMCs) are a population of circulating immune cells that are easily accessible through venipuncture. As transcriptomics is of growing importance in food and metabolism research, understanding the transcriptomic relationship between these tissue types can provide insight into the utility of PBMCs in this field.
  
  
  RESULTS
  We examine this relationship within eight subjects, in two postprandial states (following oral lipid tolerance test and oral glucose tolerance test). Multivariate analysis techniques were used to examine variation between tissues, samples, and subjects in order to define which genes havecommon/disparate expression profiles associated with highly defined metabolic phenotypes. We demonstrate global similarities in gene expression between PBMCs and white adipose tissue, irrespective of the metabolic challenge type. Closer examination of individual genes revealed this similarity to be strongest in pathways related to immune response/inflammation. Notably, the expression of metabolism-related nuclear receptors, including PPARs, LXR, etc. was discordant between tissues
  
  
  CONCLUSIONS
  The PBMC transcriptome may therefore provide a unique insight into the inflammatory component of metabolic health, as opposed to directly reflecting the metabolic component of the adipose tissue transcriptome.
authors.affiliation: Nutrigenomics Research Group, UCD Conway Institute of Biomolecular and Biomedical Research, School of Public Health and Population Science, University College Dublin, Belfield, Dublin, Ireland; Institute of Food and Health, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Colm M
authors.initials: CM
authors.lastname: O'Grada
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Morine
authors.forename: Ciara
authors.initials: C
authors.lastname: Morris
authors.forename: Miriam
authors.initials: M
authors.lastname: Ryan
authors.forename: Eugene T
authors.initials: ET
authors.lastname: Dillon
authors.forename: Marianne
authors.initials: M
authors.lastname: Walsh
authors.forename: Eileen R
authors.initials: ER
authors.lastname: Gibney
authors.forename: Lorraine
authors.initials: L
authors.lastname: Brennan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gibney
authors.forename: Helen M
authors.initials: HM
authors.lastname: Roche
mesh_terms: D052436:Adipose Tissue, White / Q000378:metabolism*; D000328:Adult; D000367:Age Factors; D000596:Amino Acids / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D005951:Glucose Tolerance Test; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology* / Q000378:metabolism; D008297:Male; D019518:Postprandial Period; D059467:Transcriptome
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D002784:Cholesterol
keywords: Nutrigenomics; PBMC; Transcriptomics; WAT