title: The expression of native and cultured human retinal pigment epithelial cells grown in different culture conditions.
abstract: OBJECTIVE
  To determine the transcriptional proximity of retinal pigment epithelium (RPE) cells grown under different culture conditions and native RPE.
  
  
  METHODS
  ARPE-19 cells were grown under five conditions in 10% CO(2): "subconfluent" in DMEM/F12+10% FBS, "confluent" in serum and serum withdrawn, and "differentiated" for 2.5 months in serum and serum withdrawn medium. Native RPE was laser microdissected. Total RNA was extracted, reverse transcribed, and radiolabelled probes were hybridised to an array containing 5,353 genes. Arrays were evaluated by hierarchical cluster analysis and significance analysis of microarrays.
  
  
  RESULTS
  78% of genes were expressed by native RPE while 45.3--47.7% were expressed by ARPE-19 cells, depending on culture condition. While the most abundant genes were expressed by native and cultured cells, significant differences in low abundance genes were seen. Hierarchical cluster analysis showed that confluent and differentiated, serum withdrawn cultures clustered closest to native RPE, and that serum segregated cultured cells from native RPE. The number of differentially expressed genes and their function, and profile of expressed and unexpressed genes, demonstrate differences between native and cultured cells.
  
  
  CONCLUSIONS
  While ARPE-19 cells have significant value for studying RPE behaviour, investigators must be aware of how culture conditions can influence the mRNA phenotype of the cell.
authors.affiliation: Johns Hopkins Hospital, Baltimore, MD 21287, USA.
authors.forename: J
authors.initials: J
authors.lastname: Tian
authors.forename: K
authors.initials: K
authors.lastname: Ishibashi
authors.forename: S
authors.initials: S
authors.lastname: Honda
authors.forename: S A
authors.initials: SA
authors.lastname: Boylan
authors.forename: L M
authors.initials: LM
authors.lastname: Hjelmeland
authors.forename: J T
authors.initials: JT
authors.lastname: Handa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018929:Cell Culture Techniques; D002460:Cell Line; D016000:Cluster Analysis; D003470:Culture Media; D016895:Culture Media, Serum-Free; D015870:Gene Expression; D020869:Gene Expression Profiling / Q000379:methods; D006801:Humans; D042282:Microdissection / Q000379:methods; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D010857:Pigment Epithelium of Eye / Q000166:cytology* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
chemical_list: D003470:Culture Media; D016895:Culture Media, Serum-Free