Circular RNA signatures of human healing and non-healing wounds

In an RNAseq analysis, we have identified the circular RNAs cCHST15 and cTNFRSF21 with high levels in venous ulcers compared to acute wounds or skin. The biological function of these two circular RNAs in human epidermal keratinocytes during wound repair has not been studied. To study the genes regulated by cCHST15 or cTNFRSF21 , we transfected siRNA targeting the diagnostic junctions of either cCHST15 or cTNFRSF21 into human primary epidermal keratinocytes to knockdown cCHST15 or cTNFRSF21 expression, respectively. We performed a global transcriptome analysis of keratinocytes upon circRNA knockdown using Affymetrix arrays. Gene expression profiling of keratinocytes transfected with either siRNA control (n = 3) or si-cCHST15 (n = 3) or si-cTNFRSF21 (n =3) for 24 hours was carried out by using human Clariom™ S assay (ThermoFisher Scientific) at the Bioinformatics and Expression Analysis (BEA) core facility at Karolinska Institutet.