Transcript Scope and Application of Stem Cell Research in Livestock

Scope and Application of Stem Cell Research
in Livestock
Jayanti Tokas1, Puneet Tokas2, Shailini Jain3, Hariom Yadav3
1Department
of Biotechnology, JMIT, Radaur, Haryana, India
2KITM, Kurukshetra, Haryana, India
3NIDDK, National Institute of Health, Bethesda, MD 20892, USA
Email: [email protected]
Stem Cell
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Stem cells are master cells with two important
characteristics
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Unspecialized cells capable of their own renewal
Ability to differentiate into different cell types
The stem cells may have various differentiation
potentials
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Totipotent
Pluripotent
Multipotent
Unipotent
Types of stem cells
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Embryonic stem
cells
Adult stem cells
Characteristics of Embryonic stem cells
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Derived from ICM/epiblast of Blastocyst
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Pluripotent
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Long-term self-renewal
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Exibit and maintain a stable diploid normal complement
of chromosome
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Expression of Oct-4
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Lacks G1 check point in the cells cycle
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Don’t show X inactivation
Stemness Genes
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Oct4
Nanog
SSEA1
SSEA2
SSEA3
BMP4
Characteristics of Adult stem cells
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Long-term self-renewal
Give rise to mature cells having characteristic
morphologies and specialized functions
Rare
Dispersed in tissues throughout the body
Origin of adult stem cells in tissues is yet not known
Tissues containing adult stem cells
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Bone marrow
Skeletal muscle
Epithelia of skin and digestive system
Cornea retina
Peripheral blood
Spinal cord
Blood vessels
Testes
Liver
Pancreas
Kidney
Heart, etc
Stem cells speciality
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Apoptosis
No apoptosis in stem cells
Telomere
No shortening of telomere in stem cells
DNA Methylation
Minimum DNA methylation in stem cells
ES cells from livestock species
Iwaski et al 1990
Saito et al 1992
ICM proportion lower in bovine IVF embryos than in vivo produced
Bovine embryonic stem cells grow slower than murine embryonic stem
cells
Hamers et al 1995 Bovine culturing embryo derived cells resemble epithelial cells rather
than pluripotent ICM cells
Talbot et al 2000 Bovine embryonic cells grew as cell sheets. Passaging by physical
dissociation
Li et al 2003
Porcine ICMs isolated by enzymatic method. Two embryonic cell lines
cultured upto 6 passages
van Eijk et al 1999 Bovine Oct 4 pseudogene isolated
Wang et al 2005
ES cells from cloned bovine embryos with marker staining
pattern similar to bovine blastocysts
Yadav et al 2005
Bovine ICM derived cells express the Oct4 ortholog
Major Applications
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Animal model testing for pharmaceutical research
Use of stem cells in transplantation and cell replacement therapy
Conservation of endangered species
Understanding fundamental events in embryonic development
Therapeutic delivery system
To resolve mysteries of developmental biology
To investigate genes involved in differentiation and development
Cell banking for research applications
Identification of stem cells
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Cell morphology
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Expression of unique cell surface antigens
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Characterization of biochemical markers such as tissue specific
enzymatic activity
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Expression of genes that are unique to a particular cell type
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Nuclear chromosomal karyotype to access genetic stability
Scope
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Pharmaceuticals: diabetes, cardiac anomalies, neurodegeneration,
and infertility
Neutraceuticals : produce heterologous nutrients
Understanding early embryonic development
Model for in vitro drug and immunity screening
Producing environment friendly animals eg. Phytase and methane
Tissue remodeling and engineering
Cell-cell communication and differentiation
Conservation
Germ stem cells challenge age old dogma of female born with fixed
number of oocytes
Livestock stem cells
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Farm animals are contributing in human health through
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Nutrition
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Producing biomedicine
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Cell therapy
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Xenotransplantation
With decoding of the genome sequences in animals,
stem cell promise to resolve many mysteries of the
developmental biology
Transgenic animals with important agricultural
traits
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Bovine alpha lactalbumin in mammary glands of sows–improves
lactation performance
Sheep carrying Kerartin – IGF-1 construct shows expression in skin
for clear fleece in transgenic animals
Transgenic pig bearing an hMt-pGH construct tightly regulated by
Zinc feeding - improves traits as growth rate, feed conversion, body
fat muscle ratio
Phytase gene exclusively expressed in salivary gland enables the
pigs to digest phytate which can be metabolized by the intestine.
Release low phosphorus in manure
Transgenic in Biomedicine
Proteins synthesized in farm animals milk
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Bovine
Caprine
Ovine
Pigs
Rabbits
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2
5
4
2
7
Human lactoferrin
TPA
Alpha AT
AT III
Alpha glucosidase