GERN:
1. Embrionic stem cells were isolated from mouse embrio in early 1980s, from other species, including primates, later.
Paper is interesting because it is first "preparation" of such cells from human embrios. Not less, not more.
2. Injection of cells into immunodeficient mice .... tired to repeat, humans are different and normally not immunodeficient.
3. It is necessary to show that:
such cells will differentiate into desirable organs (and not cancer) if injected into people.
To prevent immune reaction.
But first it will be necessary to change Federal low.
Practical applications are years from now. Ethics debates are warranted. Still, mass media are working hard. Let see what "biotech investors" had learned.
This is original paper from today Science magazine (parts). You already know Authors and the story.
Embryonic Stem Cell Lines Derived from Human
Blastocysts
For ethical and practical reasons, in many primate species, including humans, the ability of ES
cells to contribute to the germ line in chimeras is not a testable property. Nonhuman primate ES cell lines provide an accurate in vitro
model for understanding the differentiation of human tissues (4, 5). We now describe human cell lines that fulfill our proposed criteria
to define primate ES cells.
The human ES cell lines maintained the potential to form derivatives of all three embryonic germ layers. All five cell lines produced
teratomas after injection into severe combined immunodeficient (SCID)-beige mice. Each injected mouse formed a teratoma, and all
teratomas included gut epithelium...
Strategies to prevent immune rejection of the transplanted cells need to be developed but
could include banking ES cells with defined major histocompatibility complex backgrounds or genetically manipulating ES cells to
reduce or actively combat immune rejection. Because of the similarities to humans and human ES cells, rhesus monkeys and rhesus
ES cells provide an accurate model for developing strategies to prevent immune rejection of transplanted cells and for demonstrating
the safety and efficacy of ES cell-based therapies. Substantial advances in basic developmental biology are required to direct ES cells
efficiently to lineages of human clinical importance. However, progress has already been made in the in vitro differentiation of mouse
ES cells to neurons, hematopoietic cells, and cardiac muscle (22-24). Progress in basic developmental biology is now extremely rapid;
human ES cells will link this progress even more closely to the prevention and treatment of human disease.
From the same issue:
New Potential for Human Embryonic Stem Cells
John Gearhart
Embryonic stem (ES) cells were first derived from the inner cell
masses of mouse blastocysts in the early 1980s (1, 2). ...ES and EG cells have now
been derived from embryos of other mammals, including primates (5-10). Now on page 1145 of this issue, Thomson et al. (11) report
the derivation of ES cell lines from human blastocysts.
U.S. federal law bans the use of federal funds for the derivation of these cells [Public Law
105-78, Section 513(a)]. To date, research in this area has been sponsored through private and corporate funding, with hospital and
academic institutional internal review board approval and informed patient consent. It is not clear whether NIH funding necessary to
realize the biomedical potential of the cells will be available to support studies using the derived ES cells. Federal legislation and
funding policies should be reexamined in light of the biomedical potential of human ES cells
Good night.
PS: Christian, hope your influenzae leave you alone earlier than you predicted. |
