5 NP-Based Gene Delivery for Transgenesis
Transgenic animals can be produced by introduction of DNA vector into sperm
(sperm-mediated gene transfer or SMGT), metaphase oocytes (MII transgenesis) or
pronucleus-stage zygote (PN microinjection) or by introduction of viral vector into
cleavage-to-blastocyst stage embryos (Fig. 2). Alternatively, genes can be
introduced into somatic or stem cells and transfected cells used to produce embryos
via somatic cell nuclear transfer (SCNT), morula aggregation of stem cells or
blastocyst-injection of stem cells (Fig. 3). Clearly, NPs can be utilized to produce
transgenic animals via NP-based gene delivery into somatic and stem cells.
Recently, however, attempts have been made to use NP-based gene delivery system
to introduce DNA into sperm and oocytes but not into zygote or embryos.
5.1 NP-Based Gene Delivery into Sperm (nanoSMGT)
SMGT offers several advantages over other methods of transgenesis, not least of
which is its ease in methodology. Unfortunately, despite several successful reports
on efficient uptake of DNA by sperm through electroporation [125], lipofection
[126] and DMSO–DNA complex [127], generation of offspring remains low [128].
Furthermore, except for a very few selected laboratory, most researchers have
failed to produce viable offspring via artificial insemination of transfected sperm
Fig. 2 NP-based transgenic strategies. NP-loaded DNA may be transfected into sperm for spermmediated gene transfer (1), microinjected into unfertilized or fertilized oocytes (2) or magenofected
into early cleavage-stage to blastocyst-stage embryos (4). Alternatively, DNA-loaded NPs may be
delivered into stem cells (5) for production of transgenic embryos by morula aggregation of
blastocyst injection
Nanoparticles for Gene Delivery into Stem Cells and Embryos
69
Transgenic animals can be produced by introduction of DNA vector into sperm
(sperm-mediated gene transfer or SMGT), metaphase oocytes (MII transgenesis) or
pronucleus-stage zygote (PN microinjection) or by introduction of viral vector into
cleavage-to-blastocyst stage embryos (Fig. 2). Alternatively, genes can be
introduced into somatic or stem cells and transfected cells used to produce embryos
via somatic cell nuclear transfer (SCNT), morula aggregation of stem cells or
blastocyst-injection of stem cells (Fig. 3). Clearly, NPs can be utilized to produce
transgenic animals via NP-based gene delivery into somatic and stem cells.
Recently, however, attempts have been made to use NP-based gene delivery system
to introduce DNA into sperm and oocytes but not into zygote or embryos.
5.1 NP-Based Gene Delivery into Sperm (nanoSMGT)
SMGT offers several advantages over other methods of transgenesis, not least of
which is its ease in methodology. Unfortunately, despite several successful reports
on efficient uptake of DNA by sperm through electroporation [125], lipofection
[126] and DMSO–DNA complex [127], generation of offspring remains low [128].
Furthermore, except for a very few selected laboratory, most researchers have
failed to produce viable offspring via artificial insemination of transfected sperm
Fig. 2 NP-based transgenic strategies. NP-loaded DNA may be transfected into sperm for spermmediated gene transfer (1), microinjected into unfertilized or fertilized oocytes (2) or magenofected
into early cleavage-stage to blastocyst-stage embryos (4). Alternatively, DNA-loaded NPs may be
delivered into stem cells (5) for production of transgenic embryos by morula aggregation of
blastocyst injection
Nanoparticles for Gene Delivery into Stem Cells and Embryos
69