mouse embryo

Cambridge scientists create first self-developing embryo from stem cells

The transformation of a fertilised egg into a tiny living embryo ranks among nature’s most impressive feats. Now scientists have replicated this critical step towards a new life for the first time, growing an artificial mouse embryo from stem cells in the lab.

The cells, grown outside the body in a blob of gel, were shown to morph into primitive embryos that perfectly replicated the internal structures that emerge during normal development in the womb.

The scientists let the artificial embryos develop in culture for seven days – about one third of the way through the mouse pregnancy. By this point the cells had organised into two anatomical sections that would normally go on to form the placenta and the embryonic mouse.

The mouse embryo breakthrough is not designed to grow mice or babies outside the womb, but to open a new window on the embryo’s development just prior to implantation. Photograph: Redmond Durrell / Alamy/Alamy


[If you think this little guy [picture of an embryo] gets to supersede the right for any of these people who might become pregnant picture of an adult white woman, a teenage white girl, an asian woman, a black woman, and a trans man] To access the medical care that they deem the most appropriate for them, including abortions Regardless of- Why they want an abortion, How they got pregnant, How and if they were using contraception, How old they are, If they were raped or not, If they are in a relationship or not, Whether or not it is medically safe for them to carry a pregnancy to term, Whether or not they can financially afford to carry a pregnancy to term, How it would impact their lives, future, and/or safety; then you should probably know- this little guy [picture of the emryo] is a mouse embryo at 12 days from conception. But honestly, it doesn’t matter.Because even a human fetus does not get to strip people of their right to bodily autonomy. You don’t get to steal people’s kidneys to save someone else’s life.You don’t get to commandeer people’s uteruses to ensure a life is brought into the world. Keep your fingers, your opinions, and your laws out of other people’s internal organs. Let the people who are pregnant worry about their own pregnancy. ]

the-lizerd-is-here  asked:

Following my robot soul ask, would "artificial humans" have human souls too? I'm not talking designer babies. Say humans achieve creating a human from stem cells, and this human is grown up in the lab and not by a normal person. Of which, scientists have accomplished making basic mouse embryos at the moment. The same process seems likely to work for humans. Would these "artificial humans" count as human? Would they be something else? Would these humans still have a trait that colors their soul?

They would be indistinguishable from naturally born humans. Souls don’t care how you’re born.

Peripheral nerves of a mouse embryo

Unlike the brain and spinal cord that are housed in protective bone, peripheral nerves connect regions of the body to the central nervous system like telephone cables. Peripheral nerves relay movement information from the brain to the muscles, for example, or sensory information from the skin to the brain. Remarkably, and also different from the brain and spinal cord, peripheral nerves have a tremendous capacity to regenerate when injured. Severed peripheral nerves grow about 1 mm per day (about an inch per month) until the two severed ends reconnect and innervate a once paralyzed muscle.

Image by Zhong Hua, Johns Hopkins University School of Medicine.

The “Brainbow” technique is applicable to many cell types, including he muscle fibers of the tongue. Just as in the brain, the fluorescence is generated by the “Brainbow” transgene randomly recombined by the Cre/lox system. Different cell types handle the recombination step differently, leading to a unique mixture of fluorescent proteins and the colorful pattern.

Image: Here the intercrossed muscle fibers in the tongue of a mouse embryo (day 14) are labeled with random combinations of the fluorescent proteins dTomato (red), YFP (green) and Cerulean (blue). This image displays the maximal intensity projection of a confocal image stack (20x 0.8 NA oil objective).

Scientists are one step closer to understanding the genetic difference between human and chimpanzee brain development. They isolated a stretch of DNA, once thought to be “junk”, near a gene that regulates brain development. Then they added that DNA – either the human or the chimp version – to mouse embryos. Lo and behold, the mouse brains with human DNA were 12% bigger than mouse brains with chimpanzee DNA.

Eventually, work like this could generate a list of DNA sequences that give a brain some capabilities that are characteristically human. That could be important for understanding what goes wrong in diseases of the brain.

As for the ethics of such experiments:

An experiment like this recent one is not going to create mice that talk and think like people. But it could be more ethically worrisome to try to genetically enhance the brains of nonhuman primates or other reasonably intelligent animals — like pigs.

Full story, from Nell Greenfieldboyce, here.

Image: Silver Lab/Duke University

Building a functional nervous system requires many types of neurons, each with their own role to play. This image provides a snapshot of neural precursor cells (pink and yellow) in a mouse embryo that will mature into different types of spinal cord neurons (blue), depending on the signals they receive. By studying the molecular instructions that guide these and other neurons to become one type of cell or another, scientists hope to better understand how the nervous system develops

Adult mouse foot

During development, limbs begin as tiny buds at defined points along the embryo. Soon after a bud emerges, a distinct zone of cells arises called the apical ectodermal ridge (ARE), located where the tips of your fingers are as an adult. The ARE ensures the continuous, outward growth of the limb and helps organize the sculpting process for digits. Failure to maintain the ARE can result in physical deformities, such as polydactyly (multiple digits) and ectrodactyly (cleft hand).

Image by Dr. Andrew Woolley and Kevin Otto, Purdue University, Adelaide, Australia.

Light micrograph of a mouse embryo, approximately 10.5 days post-fertilisation by Jim Swoger. The specimen was stained with a fluorescent marker that highlights the presence of precursor cells to nerve tissue then chemically treated to make it optically transparent. (Royal Photographic Society’s exhibition)