Tag Archives: transplant

Printing–a new way to save a life.

A depiction of some of the many organs of the body from Achim Raschka via Wikimedia Commons.

The need for organs for people suffering from disease is ever-growing, and high.

This need has resulted in large scale ethical debates, some doctors opting for more radical ways to harvest organs. At the same time, patients are dying because they were not given a transplant promptly. The current situation in North America is dismal at best.

However, hope does exist! A recent innovation reported by a group of researchers at Heriot-Watt University could solve the problem. How you might wonder? By what scientists are calling “organ printing“.

Organ printing is a technology combining the concept of 3-dimensional printing and stem cells. A 3-dimensional printer is a machine that is able to make 3D objects when given some sort of electronic plan for the object to be printed. Traditionally, 3D printers have used metals or plastics as the ink for making objects. But instead of metal or plastic, an organ printer uses embryonic stem cells as ink; cells that are able to divide and change their identity into any other cells such as heart, lung, kidney or even brain cells, and carry out their function.

A printer that uses cells as ink could make organs! Pictures adapted from Seahen, Jomegat and Osnimf (left to right) via Wikimedia Commons.

You might wonder why this would be considered a huge breakthrough. The discovery of stem cells heralded a large amount of attention. We initially believed that we would be able to grow organs easily; however, over time, we learned that stem cells are more complex than we realized. Stem cell growth is difficult to control. Even though we can currently make a stem cell change its identity into a cell we want it to be, we cannot effectively mesh groups of cells into highly organized layers, like how complex organs such as the heart and kidneys are laid out. Experiments reported as late as three years ago could only make balls of different cell types from stem cells using chemicals. 3D printing using stem cells allows us to organize cells and distribute them the way we want them to be, and so, we could make complex structures with different layers in a consistent way in the near future.

Below, Dr. Anthony Atala talks about organ printing techniques he is researching in his lab.

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By CNN via Youtube.

But how near is the near future? I remain skeptical. Stem cells are complex things, and we have much to learn about them. Just because we place them in the right positions in the right type does not mean that all problems will be solved. Additionally, we have yet to research where to place cells so that they function the right way in an organ. I would think that this technology would take at least 10 years to be relevant to our everyday lives. Only time will tell.

-Shaun

 

The Science Affairs of Mice and Men

You may not have worried too much about Pinky and The Brain actually taking over the world in the past, but with a new procedure that transplants human brain cells into mice, the 90s cartoon may not be too far off.

Humans have two major types of cells in their brain. Neuron cells are responsible for sending electrical and chemical signals throughout your nervous system. Until now, the other type of cell has been largely ignored in regards to communication and learning. These glial cells have been thought of as structural cells that provide protection and support for neurons. The typical jobs of glial cells (purple, green and blue cells), supporting and protecting the neurons (yellow cells), are pictured below.

Via Anmats on Wikimediacommons

Researchers from the University of Rochester performed an experiment in which they transplanted human glial cells into newborn mice. When these mice reached adulthood, human glial cells had replaced a large percentage of the mice brain cells in the front areas of their brains.

Via Rama on Wikimedia commons

Testing of these mice revealed that they had an enhanced ability to learn. Analysis of their learning abilities was done using a variety of techniques, such as the Barnes maze test (pictured below). In this test mice are placed on a circular surface with visual cues on the board and many holes around the edge. The mice must locate and remember, based on the visuals provided, the hole that it can use as an escape route from the circular platform. Mice with transplanted human cells demonstrated a shorter time in completing this task. As well, they made fewer errors (choosing the wrong hole to try and escape) when completing the task.

Example of a Barnes maze setup
Via Marcoesiste on Wikimedia commons

This experiment indicates that human glial cells enhance learning and the brains ability to make new connections (neuroplasticity) in mice. In addition to creating super smart mice, this procedure also shed some light on the potential functions of glial cells in humans.

You can go to NPR and listen to an interview about neurons, glial cells and this research by clicking here

What does this mean for the human brain? The human brain is creating new connections and pathways every time you remember something or have a new thought. How much of this is strictly because of neurons, and how much relates to glial cells?

Glial cell: superstar of the brain
Via Methoxyroxy on Wikimedia commons

The evidence from this experiment supports the idea that the evolution of the human brain may be dependent on glial cells, and not just neurons. With this new information researchers need to evaluate what they believe the functions of glial cells actually are. Are they lowly structural cells or much more than that?

– Miranda Marchand