If there ever was a clear target
for first adoption in terms of growing new organs, it must be the glands like
this one. The thyroid is a strong
second. The point is that it is possible
to replace missing or damaged tissue with this protocol and it will likely be a
deliverable in around three years.
It is also likely to be well received
by the regulators as well as reversal is simple and obvious. If it is causing problems one simply removes
it again and return to the status quo.
This is no option with the way more critical organs like the heart or
kidneys.
In the meantime we are clearly
getting practical experience and it is safe to say that all organs will be
prospective for necessary replacement by 2020.
In fact I think that we can make an aggressive prediction that any human
will be restorable by 2020 to prime health.
That means all disabilities will be curable and in fact they will be
cured in order to eliminate the cost of support.
I think this prediction is aggressive
but also now extremely likely. The
momentum is clearly there.
Researchers Create a Pituitary Gland
NOVEMBER 09, 2011
The pituitary gland is a small organ at the base of the brain that
produces many important hormones and is a key part of the body's endocrine
system. It's especially crucial during early development, so the ability to
simulate its formation in the lab could help researchers better understand how
these developmental processes work. Disruptions in the pituitary have also been
associated with growth disorders, such as gigantism, and vision problems,
including blindness
The work brings us closer to being able to bioengineer complex organs for transplant in humans.
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Rathke’s pouch development in the mouse embryo.
a, Adenohypophysis originates in the non-neural head ectoderm rostral to the anterior neural plate. dorsal view. b, Immunostaining of mouse Rathke’s pouch. c, Signals from adjacent tissues to Rathke’s pouch. Scale bars, 100 μm (b).
The researchers went a step further and tested the functionality of
their synthesized organs by transplanting them into mice with pituitary
deficits. The transplants were a success, restoring levels of glucocorticoid
hormones in the blood and reversing behavioral symptoms, such as lethargy. Mice
implanted with stem-cell constructs that hadn't been treated with the right
signaling factors, and therefore weren't functional pituitary glands, did
not improve.
Next, Sasai and his colleagues will attempt the experiment with human stem cells. Sasai suspects it will take them another three years to synthesize human pituitary tissue.
Perfecting the transplantation methods in animals will likely take
another few years.
Still, researchers in the stem-cell field are impressed with what Sasai's team has accomplished. "This is just an initial step toward generating viable, transplantable human organs, but it's both an elegant and illuminating study," says Michael G. Rosenfeld, a neural stem-cell expert at the
The adenohypophysis (anterior pituitary) is a major centre for systemic
hormones. At present, no efficient stem-cell culture for its generation is
available, partly because of insufficient knowledge about how the pituitary
primordium (Rathke’s pouch) is induced in the embryonic head ectoderm. Here we
report efficient self-formation of three-dimensional adenohypophysis tissues in
an aggregate culture of mouse embryonic stem (ES) cells. ES cells were
stimulated to differentiate into non-neural head ectoderm and hypothalamic
neuroectoderm in adjacent layers within the aggregate, and treated with
hedgehog signalling. Self-organization of Rathke’s-pouch-like three-dimensional
structures occurred at the interface of these two epithelia, as seen in vivo,
and various endocrine cells including corticotrophs and somatotrophs were
subsequently produced. The corticotrophs efficiently secreted
adrenocorticotropic hormone in response to corticotrophin releasing hormone
and, when grafted in vivo, these cells rescued the systemic glucocorticoid
level in hypopituitary mice. Thus, functional anterior pituitary tissue
self-forms in ES cell culture, recapitulating local tissue interactions.
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Schematic of the SFEBq culture with large cell aggregation for
mimicking early
pituitary development. gfCDM, growth factor-free CDM.
pituitary development. gfCDM, growth factor-free CDM.
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