Cellular Function and Adhesion Mechanisms of Human Bone Marrow Mesenchymal Stem Cells on Multi-walled Carbon Nanotubes

Abstract

Multiwalled carbon nanotubes (MWCNTs) are considered to be excellent reinforcements for biorelated applications, but, before being incorporated into biomedical devices, their biocompatibility need to be investigated thoroughly. We investigated the ability of films of pristine MWCNTs to influence human mesenchymal stem cells' proliferation, morphology, and differentiation into osteoblasts. Moreover, the selective integrin subunit expression and the adhesion mechanism to the substrate were evaluated on the basis of adherent cell number and adhesion strength, following the treatment of cells with blocking antibodies to a series of integrin subunits. Results indicated that MWCNTs accelerated cell differentiation to a higher extent than tissue culture plastic, even in the absence of additional biochemical inducing agents. The pre-treatment with anti-integrin antibodies decreased number of adherent cells and adhesion strength at 4-60%, depending on integrin subunit. These findings suggest that pristine MWCNTs represent a suitable reinforcement for bone tissue engineering scaffolds.

Multiwalled carbon nanotubes enhance human bone marrow mesenchymal stem cells’ spreading but delay their proliferation in the direction of differentiation acceleration

“…Our results 12 showed that MWCNTs substrates decreased cell numbers but displayed an accelerated progression of osteoblast phenotype development, indicated by early and enhanced expression of alkaline phosphatase activity (ALP) and osteocalcin (OC) and osteopontin (OP) levels. In the absence of additional biochemical inducing agents, ALP on MWCNTs increased about fold4-as that on the control.…”

“…1 shows cell spreading on MWCNTs and TCP by fluorescent staining of the cytoskeleton f-actin (green) and DNA (blue). From data presented in Kroustalli et al, 12 areas of lower cell density were selected to facilitate observation of individual cell shapes. The images of the cells shown in the selected micrographs are typical of cells throughout the culture.…”

“…In a recent work of ours, published in Annals of Biomedical Engineering, 12 it was found that MWCNTs can create an osteogenic environment for human bone marrow mesenchymal stem cells (hBMSCs), even without addition of exogenous factors, representing a suitable reinforcement for bone tissue engineering scaffolds.…”

Evaluating the biological risk of functionalized multiwalled carbon nanotubes and functionalized oxygen-doped multiwalled carbon nanotubes as possible toxic, carcinogenic, and embryotoxic agents

“…In fact, CNTs have already been used as scaffolds for cellular or tissue growth. 2,[5][6][7] However, the essential impediments to their use in medicine continue to be uncertain about their biological safety and their influence on the human health. Although its cytotoxicity has been extensively studied, both in vivo and in vitro, as reviewed by Kayat et al,8 there are some contradictory results that can be attributed to the use of materials with different degrees of purity and structural features, 9 as well as to the conditions adopted for the in vitro studies 10 and the types of cells tested in the assays.…”

Nanotubes Reinforcement of Degradable Polymers for Orthopedic Applications

“…A focus is to use nanotubes, which reproduce the structure and length scale of bone native topography and may act as an exceptional substrate for cell growth and differentiation. 5,6 The research advances in the use of nanotubes as reinforcing agents in developing nanocomposites with synthetic and natural biodegradable polymers are reviewed. The extent of mechanical reinforcement of the polymers and the corresponding biological response of the nanocomposites are presented.…”