Investigation of osteoblast-like MC3T3-E1 cells on a novel recombinant collagen-like protein surface with triple helix structure

Abstract

Fol-8Col is a novel recombinant collagen-like protein incorporated with foldon sequences derived from the native T4 phage fibritin. In this paper, we examined the potential of using Fol-8Col as scaffold for bone tissue engineering. Circular dichroism (CD) spectra indicate that the triple helix structure of Fol-8Col exists at temperatures ranging from 4 to 40 °C. Lactate dehydrogenase assay results and live/death cell staining of osteoblast-like MC3T3-E1 cells, cultivated on Fol-8Col for 24 h, showed evidence of cell cytocompatibility comparable to that of native type I collagen. Attachment and spreading of osteoblast-like MC3T3-E1 cells seeded on Fol-8Col were studied by immunofluorescence staining of cell nuclei, vinculin, and F-actin. Intensive focal adhesion patches and an elongated cortical actin cytoskeleton were observed after 24 hours’ cultivation. Proliferation assays of MC3T3-E1 cells cultivated on Fol-8Col for 2 weeks revealed no consistent differences in rate and pattern compared to growth on type I collagen. Alkaline phosphatase activity assay and osteogenic gene expression, detected by RT-PCR, evaluated the osteogenic differentiation of MC3T3-E1 cells on Fol-8Col. This study shows that Fol-8Col, with a triple helix structure, has good potential for application in bone regeneration as a replacement for native collagen, thereby reducing the risk of contamination.