Cora H. P. Arts

A novel method for isolating pure microvascular endothelial cells from subcutaneous fat tissue ideal for direct cell seeding.

A Novel Method for Isolating Pure Microvascular Endothelial Cells from Subcutaneous Fat Tissue Ideal for Direct Cell Seeding

Application of a clinical grade CD34-mediated method for the enrichment of microvascular endothelial cells from fat tissue

BACKGROUND Microvascular endothelial cells (MVEC) derived from s.c. fat are seeded on vascular grafts to prevent early occlusion. We have demonstrated the presence of contaminating cells contributing to MVEC seeding-related intimal hyperplasia in MVEC isolates from fat tissue. We found that cell isolates additionally purified after the isolation process, were associated with a reduced thrombogenicity and development of intimal hyperplasia in vitro. A combination of 11Fibrau (F11)- and CD14-coated Dynabeads was used to deplete the contaminating cells, fibroblasts, and monocytes/macrophages. Unfortunately, clinical-grade F11 is not available, and thus cannot be used for clinical practice. CD34 selection with clinical-grade products is widely used for the isolation of hematopoietic progenitors, and endothelial cells (EC) express CD34 on their surfaces. The aims of this study were to test the effectiveness of two different CD34-selection techniques for purification of MVEC, and to compare the results with those of the F11/CD14-method. METHODS Liposuction fat was enzymatically digested and centrifuged twice to remove adipocytes and collagenase. CD34 selection was performed using the commercially available methods from Nexell or Miltenyi. Both techniques were modified for our use. The purity after isolation and culture, and recovery were determined by flow-cytometry (CD31-expression) and compared with that of cells purified with the F11/CD14-method. RESULTS Besides MVEC, the contaminating fibroblasts and macrophages/monocytes weakly expressed the CD34 Ag. Enrichment of MVEC was not successful with the Miltenyi method. Variations in neither the dose of Ab nor the use of direct selection and different separation programs improved the results. With the Nexell method, MVEC were enriched to 86%, a comparable purity to that obtained with the F11/CD14-method. However, a lower recovery was achieved with the Nexell method. CONCLUSION Enrichment of MVEC could be achieved with a modified protocol of the clinical grade CD34(+) selection method from Nexell, but not with the CD34 method from Miltenyi.

Inferior Caval Vein Thrombosis Owing to Compression of Focal Nodular Hyperplasia: Surgical Resection after Shrinkage by Hepatic Artery Embolization

The purpose of this study was to investigate the results of a staged treatment of symptomatic focal nodular hyperplasia (FNH), consisting of first embolization and then resection. A 36-year-old woman presented with pulmonary embolism caused by an inferior caval vein thrombosis owing to external compression by FNH in liver segment I (5.2 × 6.7 cm). She was treated with anticoagulants. The FNH lesion was first reduced by radiologic embolization of the feeding branch of the right hepatic artery. A 41% size reduction was obtained, and the symptoms disappeared. FNH resection was performed 5½ months later. The thrombus had disappeared, and the anticoagulant therapy could be stopped perioperatively. A symptomatic FNH lesion was treated successfully in two stages.

Cell Processing for Gene and Cell Therapy Protocols: Limitations and Opportunities!

At the UMC Utrecht, a new Gene and Cell Therapy Facility (GCT-F) for gene and cellular therapy protocols has recently been opened and is now fully operational. The main objective for building this expensive facility was to enable translation of preclinical research into clinical protocols, with an emphasis on the preparation of genetically modified cellular products.