Abstract
Purpose :
The purpose of this study was (i) to determine which mRNA and microRNA (miR) markers represent the accepted corneal allografts, (ii) to investigate the functional role of miR in allograft survival using the murine corneal allograft model and trascriptome analysis.
Methods :
Standard protocol for murine orthotopic corneal transplantation was used as described previously. Some BALB/c received syngeneic (BALB/c) grafts as a control group for the non-allospecific effects of surgery. After 4 weeks of surgery, cornea were secured and RNA was isolated and reverse-transcribed using the Superscript III Kit.
The Affymetrix Whole transcript Expression array process was executed. The sense cDNA was then fragmented and biotin-labeled with TdT (terminal deoxynucleotidyl transferase) using the GeneChip WT Terminal labeling kit. The labeled DNA target was hybridized to the Affymetrix GeneChip Mouse 2.0 ST. Hybridized arrays were stained on a GeneChip Fluidics Station and scanned on a GCS3000 Scanner. Signal values were computed using the Affymetrix® GeneChip™ Command Console software. Raw data were extracted in Affymetrix data extraction protocol and exported the result with gene level RMA analysis and performed the differentially expressed gene analysis.
Results :
Total 31,422 genes were analyzed and 1314 genes were identified in allografted corneal tissue. Compared to naïve, 624 genes were differentially expressed in syngeneic (311 upregulation and 313 downregulation) condition. From the accepted (Ac) and rejected (Rj) allograft condition, 511 and 523 genes were differentially expressed compared to naïve cornea, respectively. Morever, 139 genes were upregulated and 81 genes were downregulated in Ac, compared to Rj cornea. Compared miR expression in donor cornea from syngeneic, Rj and Ac allograft (n=8), 83 and 54 genes were identified as differentially regulated by miRs in Ac and in Rj, respectively. With miR and mRNA negative regulation paring analysis, we identified 9 and 7 miRs which showed clear correlation in Ac versus syngeneic and in Rj versus syngeneic analysis, respectively (p<0.001).
Conclusions :
Corneal allograft acceptance is not a simple quiet status but a condition of actively inducing miRs and mRNAs in murine graft. At least 9 miRs and mRNA sets were found to correlated negatively and may regulate graft survival actively.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.