Detection of minimal but significant amount of von Willebrand factor in human omentum mesothelial cell cultures

Efendy

1999

Circulation Research

266

211

—A method by which to overcome the clinical symptoms of atherosclerosis is the insertion of a graft to bypass an artery blocked or impeded by plaque. However, there may be insufficient autologous mammary artery for multiple or repeat bypass, saphenous vein may have varicose degenerative alterations that can lead to aneurysm in high-pressure sites, and small-caliber synthetic grafts are prone to thrombus induction and occlusion. Therefore, the aim of the present study was to develop an artificial blood conduit of any required length and diameter from the cells of the host for autologous transplantation. Silastic tubing, of variable length and diameter, was inserted into the peritoneal cavity of rats or rabbits. By 2 weeks, it had become covered by several layers of myofibroblasts, collagen matrix, and a single layer of mesothelium. The Silastic tubing was removed from the harvested implants, and the tube of living tissue was everted such that it now resembled a blood vessel with an inner lining of nonthrombotic mesothelial cells (the “intima”), with a “media” of smooth muscle–like cells (myofibroblasts), collagen, and elastin, and with an outer collagenous “adventitia.” The tube of tissue (10 to 20 mm long) was successfully grafted by end-to-end anastomoses into the severed carotid artery or abdominal aorta of the same animal in which they were grown. The transplant remained patent for at least 4 months and developed structures resembling elastic lamellae. The myofibroblasts gained a higher volume fraction of myofilaments and became responsive to contractile agonists, similar to the vessel into which they had been grafted. It is suggested that these nonthrombogenic tubes of living tissue, grown in the peritoneal cavity of the host, may be developed as autologous coronary artery bypass grafts or as arteriovenous access fistulae for hemodialysis patients.

Section: Formation Of a Granulation Tissue Tube In The Peritoneal Cavitymentioning

confidence: 83%

Section: Granulation Tissue Tube As Autologous Vascular Graft (Artifimentioning

confidence: 99%

Novel Vascular Graft Grown Within Recipient’s Own Peritoneal Cavity

Efendy

1999

Circulation Research

266

211

“…During the first 3 days after implantation the foreign body became covered with rounded cells that stained with FITC-labelled antibodies to Ly5 (either 5.1 or 5.2 depending on the strain of mouse) (fig. 1a, 2a) indicating that they are of haemopoietic origin [17, 18]. Similarly, cells of the early capsule and freshly harvested from the peritoneal cavity stained for CD68.…”

Section: Resultsmentioning

confidence: 99%

“…By day 7 a distinct capsule composed of multilayered macrophages had formed covered by a single layer of flattened, von Willebrand factor-staining cells (fig. 1b, 2b) which were thought to be mesothelial cells from the peritoneal lining [17]. By this time most cells of the main body of the capsule had lost their staining for Ly5 and CD68.…”

Section: Resultsmentioning

confidence: 99%

Haemopoietic Origin of Myofibroblasts Formed in the Peritoneal Cavity in Response to a Foreign Body

et al. 2000

This study utilized both in vivo and in vitro techniques to investigate whether cells of bone marrow origin can differentiate into smooth muscle-like cells (myofibroblasts) with contractile filaments and proteins. Female C57BL/6 mice expressing the Ly5.2 antigen on the surface of their haemopoietic cells had four pieces of silastic tubing (3 × 0.5 mm outer diameter) or boiled blood clot (2–3 mm diameter) placed in their peritoneal cavity. After 3, 5, 7 and 14 days (n = 4/group) the implants were removed and those that had remained free-floating were processed for light microscopy, immunohistochemistry and electron microscopy. In the first 3–5 days, rounded cells adhered to the entire surface of the tubing then flattened. These cells stained with fluoresceinated antibodies to Ly5.2 showing that they were derived from haemopoietic cells. By 14 days the cells had become elongated and multilayered in a collagen matrix, forming a thick tissue capsule around the tubing or boiled clot. They contained contractile filaments and stained with antibodies to α-smooth muscle actin but no longer stained for Ly5.2. A separate set of female C57BL/6 Ly5.2 mice were X-irradiated to destroy bone marrow then immediately transfused with 10⁶ nucleated bone marrow cells taken from the femur and tibia of a congenic strain of male mice expressing the Ly5.1 allele. Eight of the female mice with successful engraftment (80–99%) had silastic tubing implanted in the peritoneal cavity. After 14 days, in situ hybridization with Y chromosome probe confirmed the male donor, and thus bone marrow, origin of the elongated cells that formed the capsule. In vitro studies showed that cells of the murine macrophage cell lines RAW 264.7 and J774 express α-smooth muscle actin after exposure to the cytokine γ-interferon in vitro. These data show that bone marrow-derived cells can differentiate into smooth muscle-like cells and raises the possibility that blood-derived cells may contribute to the development of fibro-proliferative vascular diseases such as atherosclerosis.

Biotech and App Biochem

“…These have been characterized as mesothelial cells (MC) [13]. Both EC and MC have a similar function producing substances such as tissue‐type plasminogen activator (‘tPA’) and urokinase plasminogen activator [14,15]. In animal experiments, most trials involving the seeding of grafts using cells derived from omentum have shown good results [16–21], except those reported by Verhagen and co‐workers [22].…”

Section: Introductionmentioning

confidence: 99%

Extraction of cells for single‐stage seeding of vascular‐bypass grafts

Tiwari

Kidane

Punshon

et al. 2003

Experimental data are reported for the seeding of prosthetic vascular grafts with either mesothelial or endothelial cells as part of a research strategy in tissue engineering with the aim of improving graft patency and developing new techniques for single-stage cell extraction and seeding that would give a step reduction in surgery time. New data are reported for two different sources of cells, peritoneal lavage and subcutaneous fat. All experiments were undertaken in patients undergoing abdominal aortic aneurysm repair. Cells extracted from peritoneal lavage were insufficient for a single-stage seeding process. Subcutaneous fat was processed using either a positive cell-extraction method using CD31 Dynabeads or by a negative extraction method using CDw90-coated magnetic beads. Only positive cell extraction gave reliably sufficient numbers of endothelial cells as a source for single-stage seeding of vascular grafts.