Introduction. Intimal hyperplasia (IH) is characterized by concentric lumen constriction due to marked vascular cell proliferation and is associated with arteriovenous fistula (AVF) early failure in haemodialysis patients. Aim. The present study aimed at establishing ex-vivo cell cultures from patients enrolled for AVF procedure, in order to identify the main cellular and molecular mediators of IH. Methods. Tissues and cells were collected from i) normal veins taken when the first AVF was established, and ii) AVF with IH. Formalin-fixed paraffin-embedded tissue sections were stained with anti CD34, CD44 and MMP-9 monoclonal antibodies. Isolated vascular cells were investigated for bromo-deoxy-uridine incorporation, and migration ability; immunofluorescence (CD34, CD44, ASMA, SOX9) was used to characterize the cell phenotype. Results. Tissue detection of CD34+, CD44+ cells within the IH lesions suggested the involvement of endothelial cells in AVF failure. The expression of MMP-9 protein in the same area supported the activation of migration/matrix remodeling pathways, typical of mesenchymal cells. This same immunophenotype was observed in the cells harvested from IH lesions, together with the detection of ASMA. We observed significant growth differences between cells isolated from normal veins and AVF with IH. Indeed, cells from IH grew faster than cells from normal veins; moreover, IH cells expressed higher levels of SOX9, a transcription factor associated with cell proliferation, and exhibited a marked migration property. Conclusion. Our data evidence that, when compared with cells harvested from not diseased veins, cells derived from AVF with IH have increased proliferation, migration and remodeling abilities. The immunophenotype documented in tissue and cell studies suggests that the endothelial-mesenchymal transition is involved in IH formation and progression. This preliminary study will be expanded with further investigations on IH induction mechanisms and on possible therapeutic targets.
Ciavarella C, V.F. (2019). An ex-vivo cell model for studying intimal hyperplasia in AVF failure.
An ex-vivo cell model for studying intimal hyperplasia in AVF failure
Ciavarella C;Vasuri F;Mauro R;Pini R;Faggioli GL;Gargiulo M;La Manna G;Pasquinelli G
2019
Abstract
Introduction. Intimal hyperplasia (IH) is characterized by concentric lumen constriction due to marked vascular cell proliferation and is associated with arteriovenous fistula (AVF) early failure in haemodialysis patients. Aim. The present study aimed at establishing ex-vivo cell cultures from patients enrolled for AVF procedure, in order to identify the main cellular and molecular mediators of IH. Methods. Tissues and cells were collected from i) normal veins taken when the first AVF was established, and ii) AVF with IH. Formalin-fixed paraffin-embedded tissue sections were stained with anti CD34, CD44 and MMP-9 monoclonal antibodies. Isolated vascular cells were investigated for bromo-deoxy-uridine incorporation, and migration ability; immunofluorescence (CD34, CD44, ASMA, SOX9) was used to characterize the cell phenotype. Results. Tissue detection of CD34+, CD44+ cells within the IH lesions suggested the involvement of endothelial cells in AVF failure. The expression of MMP-9 protein in the same area supported the activation of migration/matrix remodeling pathways, typical of mesenchymal cells. This same immunophenotype was observed in the cells harvested from IH lesions, together with the detection of ASMA. We observed significant growth differences between cells isolated from normal veins and AVF with IH. Indeed, cells from IH grew faster than cells from normal veins; moreover, IH cells expressed higher levels of SOX9, a transcription factor associated with cell proliferation, and exhibited a marked migration property. Conclusion. Our data evidence that, when compared with cells harvested from not diseased veins, cells derived from AVF with IH have increased proliferation, migration and remodeling abilities. The immunophenotype documented in tissue and cell studies suggests that the endothelial-mesenchymal transition is involved in IH formation and progression. This preliminary study will be expanded with further investigations on IH induction mechanisms and on possible therapeutic targets.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
