PTGDR influences cytokine levels in theA549 cell line

Resumen

Introduction:PTGDR is the receptor for prostaglandin D2 (PDG2),a mediator that participates in the allergic airway inflammation inasthma. ThePTGDRgene is a candidate gene in allergy and asthma.Functional studies suggest a possible role of polymorphisms of thepromoter region in the susceptibility to asthma. Objectives:Considering the role of PTGDR in allergy, the goal ofthis study was to analyze the effect ofPTGDRexpression on cyto-kine levels in the A549 cell line.Results:We generated lung epithelial cells expressingPTGDRbytransfection of fusion vectors (pCTCT-PTGDRand pCCCC-PTGDR)into A549 cells. RNA was isolated from transfected cells and used toanalyzePTGDRexpression in A549 cell cultures. Cytokine productionassays in the culture supernatant were measured by cytometric beadassay using the BioPlexProTMHuman Cytokine standard 27-plex,Group I. The assays were conducted with BioPlex High-throughputfluidics system, powered by the Luminex Technology. Every samplewas run at least in triplicate. ThePTGDRexpression in the trans-fected cells with the haplotypic variants differed by 5 orders of mag-nitude relative to control cells (P<.001). We found significantdifferences inPTGDRexpression between CTCT and CCCC haplo-typic variants. The CCCC (613 C,549 C,441 C, and197 C)haplotype showed significantly higher expression compared with thewild variant CTCT. At 24 hours thePTGDRexpression after normal-ization (meanSD) was expressed as fold increments. Consideringthe wild variant CTCT as value 1, the CCCC showed 1.400.08)(P=.02). We compared the cytokine production of A549 transfectedcells among the differentPTGDRhaplotypic variant CTCT, CCCC andcontrol cells. Culture supernatant levels of IL-4, IL-6, IL-7, IL-8, andTNF-ain A549 transfected cells were significantly higher comparedwith control cells (P<.05).Conclusions:We detect an increase of the Th2 cytokine IL-4, thepro-inflammatory cytokines IL-6, IL-8 and TNF-aand the B-cell mat-uration factor IL-7, in both CTCT- and CCCC-PTGDR transfectedcells supporting the role ofPTGDRin the cytokine response of cells