title: Immune system transcriptome in gingival tissues of young nonhuman primates.
abstract: OBJECTIVE
  Young/adolescent humans harbor many microorganisms associated with periodontal disease in adults and show substantial gingival inflammatory responses. However, younger individuals do not demonstrate the soft- and hard-tissue destruction that hallmark periodontitis.
  
  
  METHODS
  This study evaluated responses to the oral microbial ecology in gingival tissues from clinically healthy young Macaca mulatta (< 3 years of age) compared with older animals (5-23 years of age). RNA was isolated from the tissues and analyzed for the transcriptome using the Rhesus Macaque GeneChip (Affymetrix).
  
  
  RESULTS
  Global transcriptional profiling of four age groups revealed a subset of 159 genes that were differentially expressed across at least one of the age comparisons. Correlation metrics generated a relevance network abstraction of these genes. Partitioning of the relevance network revealed seven distinct communities comprising functionally related genes associated with host inflammatory and immune responses. A group of genes was identified that were selectively increased/decreased or positively/negatively correlated with gingival profiles in the animals. A principal components analysis created metagenes of expression profiles for classifying the 23 animals.
  
  
  CONCLUSIONS
  The results provide novel system-level insights into gene-expression differences in gingival tissues from healthy young animals, weighted toward host responses associated with anti-inflammatory biomolecules or those linked with T-cell regulation of responses. The combination of the regulated microenvironment may help to explain the apparent 'resistance' of younger individuals to developing periodontal disease.
authors.affiliation: Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY, USA.
authors.forename: O A
authors.initials: OA
authors.lastname: Gonzalez
authors.affiliation: Division of Biomedical Informatics, College of Public Health, University of Kentucky, Lexington, KY, USA.|Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, KY, USA.
authors.forename: R
authors.initials: R
authors.lastname: Nagarajan
authors.affiliation: Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Novak
authors.affiliation: School of Dentistry, University of Puerto Rico, San Juan, Puerto Rico.
authors.forename: L
authors.initials: L
authors.lastname: Orraca
authors.affiliation: Caribbean Primate Research Center, Sabana Seca, Puerto Rico.
authors.forename: J A
authors.initials: JA
authors.lastname: Gonzalez-Martinez
authors.affiliation: Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Kirakodu
authors.affiliation: Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Ebersole
mesh_terms: D000818:Animals; D005881:Gingiva; D007107:Immune System; D008253:Macaca mulatta; D020411:Oligonucleotide Array Sequence Analysis; D010518:Periodontitis; D059467:Transcriptome
keywords: aging; inflammation; nonhuman primates; periodontitis