Cell and tissue adaptation in the pulmonary autograft in a large animal model of the Ross procedure

In the Ross procedure, a patient's pulmonary valve is transplanted into aortic position. Reoperation is needed in many cases due to failure through dilatation of the pulmonary autograft. To further understand the failure mechanisms, gene expression profiling of the autograft tissue was performed and compared to control aortic and pulmonary sinus tissue though bulk RNA-seq. Notable results include the upregulation of inflammatory pathways and genes coding for proteins important for the structural integrity of the tissue, such as extracellular matrix proteins, collagenases and elastases. Overall design: In three sheep, the pulmonary root was transplanted into aortic position to form the pulmonary autograft. Six months after the surgery, autograft sinus tissue was extracted to perform gene expression profiling though RNA-seq in these three sheep. Pulmonary sinus and aortic sinus tissue was extracted from non-operated sheep to perform gene expression profiling through RNA-seq as control.