Analysis of cellular morphology, adhesion, and proliferation on uncoated and differently coated PVC tubes used in extracorporeal circulation (ECC)

Abstract

The biggest challenge to improve extracorporeal circulation (ECC) circuits lays on avoiding platelet adhesion to their surfaces, because this contributes to thrombus formation, resulting in the activation of blood coagulation. One approach to minimize this effect is to improve the biocompatibility of ECC circuits by modifying their surfaces. This can be achieved by coating them with heparin or phospholipids. The present study investigated the adhesion and morphology characteristics of fibroblastic and blood cells cultured on uncoated poly (vinyl) chloride PVC tubes as well as on heparin, phosphatidylcholine (DMPC), and phosphatidylethanolamine (DMPE) -coated tubing. The results showed the importance of uniform coating regardless of the substance used, because the coatings cover the grooves on PVC surfaces, which favor cell adhesion. The comparison among the three different coatings showed the best biocompatibility results for the PVC tubes coated with heparin, followed by the coating with DMPE and with DMPC. For all coated tubes, cells did not spread on the PVC surfaces and, consequently, did not adhere to their surfaces, increasing the overall biocompatibility of PVC tubes. However, possible DMPE's alkylation, caused by sterilization, resulted in increased material hydrophobicity, which explains the decrease in fibroblastic adhesion. Furthermore, sterilization of DMPC-PVC improves its hydrophilic character, also decreasing adhesion. Based on these results, coating PVC with the phospholipids DMPC and DMPE seems to be a promising technique to improve the biocompatibility of PVC tubes, and is worthy of further investigation.

A novel small animal model for biocompatibility assessment of polymeric materials for use in prosthetic heart valves

“…Chen et al35 found that phosphorylcholine dip‐coated ePTFE grafts significantly reduced platelet deposition and neointimal hyperplasia in a dog model of arteriovenous grafts. Moreira et al36 evaluated the adhesion and morphology characteristics of fibroblastic and blood cells cultured on uncoated poly(vinyl) chloride (PVC) tubes and on DMPC dip‐coated PVC tubing. Cells did not spread on the DMPC‐coated surfaces and, consequently, did not adhere to their surfaces.…”

Immunomodulation due to plasma or plasma–platelet apheresis donation: Events occurring during donation procedures

“…The circuits of apheresis donor procedures are made with the identical biocompatible plastic as therapeutic apheresis; hence, it is conceivable that also during the donation a boundary layer could form as a result of the adsorption of plasma proteins to plastic membranes made of various synthetic polymers. Moreover, donors' leukocytes can be activated by the interaction with plastic circuits during the procedure , thus becoming sensitive to sHLA‐I modulation, which has been shown to occur only in activated leukocytes . Indeed, healthy donors' leukocytes are only transiently activated by contact with circuits; therefore, they should show only an ephemeral sensitivity to sHLA‐I mediated immunomodulation, unlike that reported with therapeutic procedures.…”

Self-assembled hemocompatible coating on poly (vinyl chloride) surface

“…Vero is a fibroblastic cell line established from the kidney of the African green monkey (Cercopithecus aethiops). It is recommended for studies of cytotoxicity and cell-substratum interactions in the biomaterials research area [1,49]. The culture medium was DMEM (Dulbecco's Modified Eagle's Medium) supplemented with 10% (v/v) fetal bovine serum.…”

“…The clinical application of devices and materials in contact with blood, such as extracorporeal circulation circuit (ECC), hemodialysis systems and blood bypass tubes, among others, is of major importance in modern medicine [1]. PVC is a blood contacting biomaterial of high interest because of its widespread application in blood and blood component storage bags, catheters, and tubing for ECC devices, which have contributed significantly to the quality and effectiveness of the health care system [2][3][4].…”