Posts Tagged: Igf1

RADA16-I peptide hydrogel, a type of nanofiber scaffold derived from self-assembling

RADA16-I peptide hydrogel, a type of nanofiber scaffold derived from self-assembling peptide RADA16-I, has been extensively applied to regenerative medicine and tissue repair in order to develop novel nanomedicine systems. to type I collagen. The precultured ovarian cancer cells had two-fold to five-fold higher anticancer Igf1 drug resistance than the conventional two-dimensional Petri dish culture. So the 3D cell model on peptide nanofiber scaffold is an optimal type of cell pattern for anticancer drug screening and tumor biology. value < 0.05 indicated the statistically significant differences (*< 0.05; **< 0.01). Results and discussion Molecular characterization of RADA16-I peptide nanofiber scaffold Molecular self-assembling peptide RADA16-I derived from a Lego peptide segment of Zuotin, a left-handed Z-DNA-binding protein originally discovered in yeast, with alternating alanine and amino acid residues, has recently emerged as a novel nanobiomaterial for regenerative medicine and tissue repair.15C17 RADA16-I peptide served as the building block of nanofiber scaffold 10 nm in diameter with the drive of positively and negatively charged residues by complementary ionic interactions and spontaneously assembled into the well-ordered nanofiber networks with the pore size of about 5C200 nm (Figure 1A and B). When dissolved in Milli-Q H2O, RADA16-I peptide existed as the stable hydrogel with extremely high water content (>99.5%) at 1C5 mg/mL (w/v). The in situ AFM scan exhibited that RADA16-I peptide nanofiber scaffold consisted of the nanofiber with length 1019.83 90.16 nm and diameter 32.37 1.72 nm (Figure 1C and D), which closely mimicked the porosity and gross structure of extracellular matrices (ECMs) and was suitable for the fabrication of the artificial cell niches for the applications of tumor biology and regenerative medicine. When desired, the cancer cells could be easily encapsulated into the nanofiber networks in a truly 3D microenvironment. When mixed with the ovarian cancer cells, the peptide nanofiber hydrogel formed the regular cancer cellCnanofiber scaffold construct, which was readily mounted on the bottom of the wells in a Petri dish. The cancer cells LY2157299 were evenly distributed and enabled the user to develop the different cell patterns in line with the particular purpose of cell biology. LY2157299 The operation procedure was very simple and convenient in the laboratory. Figure 1 Molecular self-assembling peptide RADA16-I was evaluated by TEM and AFM. A) Molecular model of RADA16-I with 16 amino acid residues and the alternating positive and negative residues arrangement. B) TEM of RADA16-I peptide nanofiber (magnified … Morphology and proliferation of ovarian cancer cells As 3D cell models for ovarian cancer, A2780, A2780/DDP, and SK-OV-3 cell lines were chosen; the A2780 cells had nearly the same features as A2780/DDP, besides the different drug resistance. SK-OV-3 cells had slow growth activity. The ovarian cancer cellCpeptide nanofiber construct cast in the 24-well Petri dish was of a particular transparent morphology that enabled LY2157299 the convenient capture of cell images by the phase contrast microscopy. The cancer cellCpeptide nanofiber scaffold interactions were intimate and clear-cut in appearance. The peptide nanofibers were densely enmeshed with each other, and the cancer cells gradually integrated with the surrounding nanofibers as cell growth proceeded. On the first day, the cancer cells of A2780, A2780/DDP, and SK-OV-3 were evenly distributed and maintained inherent morphology (Figure 2A, D, and G). After 3 days, cell density increased; simultaneously, the cells closed up and presented distinctive appearances. A2780 and A2780/DDP cells initially formed cell colonies, whereas SK-OV-3 cells proliferated slowly and maintained their individual cellular appearance (Figure 2B, E, and H). After 7 days, A2780 and A2780/DDP cells formed the multicellular spheroids (Figure 2C and F), whereas SK-OV-3 cells formed the cell clusters (Figure 2I), which were the typical morphologies of cancer cells in 3D cell culture and the common characteristics of the glandular epithelial tumors. As 3D cell culture continued, the cell morphologies of A2780, A2780/DDP, and SK-OV-3 cells maintained the inherent characteristics, and SK-OV-3 cells did not form the multicellular spheroids. The more detailed morphologies of A2780, A2780/DDP, and SK-OV-3 cells were difficult to observe in the laboratory. The use of RADA16-I peptide hydrogel to culture cancer cells should improve our understanding of the disease.