Biomedical Engineering Reference
In-Depth Information
Fig. 12
Cluster of cells are fully embedded in the self-assembling peptide nanofi ber scaffold. The
scales of the nanofi bers are on the similar scale as the native extracellular matrices. Such 3-D cell
clusters are nearly impossible to form in the 2-D culture systems
4.4
Self-Assembling Peptides Nanofi ber
Scaffold 3-D Cell Culture
The importance of nanoscale becomes obvious in 3-D cell culture. It is clearly vis-
ible in the scanning electron microcopy (SEM) images that the cells embed in the
self-assembling peptide nanofi ber biological scaffolds in the truly 3-D culture
(Fig.
12
). Here, the cells and cell clusters intimately interact with the extracellular
matrix that the cells make on their own. Since the scaffolds are made mostly of
water, ~99% water at 1% peptide solid, cells can migrate freely without hindrance.
These new self-assembling peptide nanofi ber biological scaffolds have become
increasingly important not only in studying spatial behaviors of cells, but also in
developing approaches for a wide range of innovative medical technologies includ-
ing regenerative medicine (Fig.
13
). One example is the use of the peptide scaffolds
to support neurite growth and differentiation, neural stem cell differentiation, car-
diac myocytes, bone and cartilage cell cultures. The peptide scaffolds from
RADA16-I and RADA16-II form nanofi ber scaffold in physiological solutions that
stimulated extensive rat neurite outgrowth, and active synapses formation on the
peptide scaffold was successfully achieved (Holmes et al.
2000
) .
4.5
Designer Peptides Scaffold 3-D Cell Cultures
A variety of mammalian cells have been cultured on designer self-assembling pep-
tide nanofi ber scaffolds (Table
1
). In a recent work we directly and systematically
compared neural stem cell adhesion and differentiation on self-assembling
RADA16-I scaffolds with other natural-based substrates including laminin, Collagen I,
fi bronectin and some of the most commonly used synthetic biomaterials in tissue
