Abstract No. 94: Bone marrow derived cells do not contribute to venous neointimal hyperplasia (VNH) in a murine model of arteriovenous fistula with chronic kidney disease

Abstract

In arterial stenosis, bone marrow derived cells have been shown to contribute to stenosis formation. We hypothesized that bone marrow derived cells may contribute to the formation of VNH in a murine model of arteriovenous fistula with chronic kidney disease. Donor mice (sm22-GFP C57BL/6) mice were killed, and their femurs and tibias removed aseptically. Marrow cavities were flushed, and single-cell suspensions prepared. Cells were washed 2 times in HBSS and resuspended at 3x107 cells/ml before transplantation. Six- to 8-week-old C57BL/6 mice received a lethal dose of whole-body irradiation at 8.5-9.0 Gray units of gamma irradiation exposure for 14.2 minutes. Irradiated recipients received 1X 107 bone marrow cells in 0.3 ml into the femoral vein within 24 hours of irradiation. Four weeks after bone marrow transplantation, a right nephrectomy was performed and the upper pole of the left kidney ligated. Four weeks later, a AVF was created from the left carotid artery to the ipsilateral jugular vein. Animals were sacrificed at day 3, 7, and 14 after fistula creation and the outflow vein embedded in paraffin for histochemical analysis. 16 mice were used and 4 died after radiation and 4 mice had thickened carotid arteries which excluded them from placement of the AVF. Therefore 8 animals were sacrificed at D3 (n=3), D7 (n=3), and D14 (n=2). Confocal microcopy for GFP was performed on paraffin embedded sections. No eGFP positive cells were identified at the venous stenosis. No eGFP bone marrow derived cells contributed to VNH formation in a murine model of AVF failure.