ABSTRACT
Transcriptome analyses of organ transplants have until now usually focused on whole tissue samples containing activation profiles from different cell populations. Here, we enriched endothelial cells from rat cardiac allografts and isografts, establishing their activation profile at baseline and on days 2, 3 and 4 after transplantation. Modulated transcripts were assigned to three categories based on their regulation profile in allografts and isografts. Categories A and B contained the majority of transcripts and showed similar regulation in both graft types, appearing to represent responses to surgical trauma. By contrast, category C contained transcripts that were partly allograft-specific and to a large extent associated with interferon-gamma-responsiveness. Several transcripts were verified by immunohistochemical analysis of graft lesions, among them the matricellular protein periostin, which was one of the most highly upregulated transcripts but has not been associated with transplantation previously. In conclusion, the majority of the differentially expressed genes in graft endothelial cells are affected by the transplantation procedure whereas relatively few are associated with allograft rejection.
Subject(s)
Endothelium, Vascular/physiology , Genome-Wide Association Study , Heart Transplantation/pathology , Transcription, Genetic , Animals , Cluster Analysis , Gene Expression , Gene Expression Profiling/methods , Graft Survival/physiology , Leukocyte Common Antigens/blood , Leukocyte Reduction Procedures , Male , Neck , RNA/genetics , RNA/isolation & purification , Rats , Reperfusion Injury/genetics , Reverse Transcriptase Polymerase Chain Reaction , Transplantation, Heterotopic/methods , Transplantation, Homologous/physiology , Transplantation, Isogeneic/physiologyABSTRACT
Out of 49 serially studied juxtaglomerular apparatuses, 6 typical variants from two normal human kidneys were reconstructed graphically. The agranular Goormaghtigh cells filled the entire space between the macula densa, the afferent and the efferent arterioles and the glomerular mesangium. The Goormaghtigh cells were always in direct contact with all the other structures. They also invariably continued into the glomerular mesangium. The distal tubule regularly showed widening in the macula densa segment and, at this level, there was considerable variation in the shape of the distal tubule. Direct contact between the macula densa and the hilar arterioles was not always present, the area of contact was usually greater with the afferent than with the efferent arteriole.
