Biomedical Engineering Reference
In-Depth Information
Chapter 13
Delivery of Molecules and Genes/Small
Interfering RNA into Stem Cells by
Nanoengineering
Mohsen Ashjari
1,2
1
Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan, Iran
2
Department of Stem Cells and Developmental Biology at Cell Science Research Center,
Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
Introduction
Nanotechnology, the engineering and manufacture of efficient systems at molecular and
atomic scales, has overshadowed many aspects of today's medicine. This technology has rev-
olutionized pharmaceutical, medical therapeutics, and diagnostics through the development
of ingenious nanodevices [1].
Stem cells are unspecialized, clonogenic cells that, according to their potency, can differ-
entiate into multiple types of differentiated cells from one or all three primitive embryonic
germ layers (ectoderm, mesoderm, and endoderm) in response to specific signals. Stem cells
possess two capacities to self-renew and make copies of themselves and differentiate into
organs and tissues. Generally, stem cells differentiate into intended cellular tissue by
induction of growth factors, genes, and proteins. The ability to accurately and efficiently
differentiate stem cells into all lineages is the subject of intense research [2].
Recently, engineering has become an important strategy for the induction and regulation
of differentiation of stem cells into specific cell types. Because stem cells can be grown long
term
in vitro
, their genetic modification prior to transplantation provides a unique opportu-
nity for correction of genetic defects [3].
Conventionally, cellular delivery strategies, such as electroporation and microinjection,
nucleofection, retro-viral transduction, and cationic liposomes are well-known, however, their
application in embryonic stem cells (ESC) is both a time and labor-intensive process. Nonviral
carriers have emerged based on polymers or similar materials. These carriers in comparison
with viral carriers exhibit low gene efficiency and cytotoxicity in numerous trials [4].
Nanotechnology-based intracellular delivery is a relatively recent concept in stem-cell
research and development, and “nanoengineering” is the application of nanotechnology in
stem-cell engineering. The concept of nanoengineered nonviral delivery into stem cells may
be of value if biologically active agents can be incorporated onto nanocarriers. The goal of
such nanocarriers is to enhance agents' uptake by stem cells without the limitations found in
viral delivery that include infection-related cell damage and immune response issues [5]. For
example, the complexation of DNA with a nanoparticle avoids numerous viral delivery
