Researchers Discover Bacteria That Can Transform Regular Cells Into Stem Cells

Stem cells (green) carrying bacteria differentiate into skeletal muscles, passively transmitting the infection to muscles.
Credit: Dr Toshihiro Masaki, MRC Centre for Regenerative Medicine, The University of Edinburgh

Researchers discover that bacteria can transform regular stem cells into stem cells. This discovery can lead to better stem cell treatments in the future.

Pluripotent Stem Cells are being considered the next best miracle cure for most diseases. Its pluripotency is what makes these cells special when it comes to medical science. Pluripotency is the ability to change into any other type of cell or tissue. This process is called differentiation.

There are different kinds of stem cells. There are blood stem cells, cardiac stem cells, brain stem cells and others. These can only differentiate into a specific cell or tissue. Only embryonic stem cells are pluripotent and can differentiate into any other cell except into another embryo.

Stem cell research hit a snag when President Bush vetoed the Stem Cell Research Enhancement Act of 2005 allowing the federal funding of embryonic stem cells because of moral reasons. Scientists were permitted to use existing stem cell lines harvested before the bill was vetoed.

In 2007, Shinya Yamanaka and his team at Kyoto University successfully transformed a non-pluripotent cell into a pluripotent stem cell without using embryonic stem cells. This was done by inducing specific genes within the cells to revert back to being pluripotent again. Yamanaka and fellow stem cell researcher John Gurdon were awarded the Nobel Prize in Physiology or Medicine "for the discovery that mature cells can be reprogrammed to become pluripotent."

Currently, there are four types of pluripotent stem cells:

• Embryonic Stem Cell
• Nuclear Transplant Stem Cell
• Parthenote Stem Cell
• Induced Stem Cell

The first three types require a fertilized egg cell to form.

Scientists are looking into stem cells as treatment for incurable diseases such as diabetes, Alzheimer's Disease, and cancer.

Creating New Beta Cells: Stem Cell Advances For Diabetes Treatment

The islets of Langerhans are responsible for the endocrine function of the pancreas. Each islet contains beta, alpha, and delta cells that are responsible for the secretion of pancreatic hormones. Beta cells secrete insulin, a well-characterized hormone that plays an important role in regulating glucose metabolism.

Stem cell treatment for diabetes is slowly progressing as scientists study the process of regenerating insulin producing beta cells from stem cells.

Diabetes is a disease where production of insulin by the, the hormone that regulates blood sugar levels, is either not enough or not even produced.

Insulin is created in the pancreas, as part of the body's endocrine system. Within the pancreas, in a region called the islets of Langerhans are cells called Beta cells. These beta cells are the cells responsible for the actual production and secretion of insulin.

Diabetes occurs when these beta cells stop producing insulin or does not produce enough. The number of beta cells in the body are kept in balance within the pancreas. Studies have shown that obese people who have not contracted diabetes have a higher amount of beta cells than obese diabetics.

Stem Cells

Stem cells are special cells that can differentiate (transform) into a higher or specialized type of cell. The body has different types of stem cells such as blood stem cells, heart stem cells, and even brain stem cells. These cells can only differentiate into cells specific to the organ they are associated with.

There are also pluripotent stem cells that can differentiate into any type of cell. These are embryonic stem cells. But because embryonic stem cells are harvested from living embryos, some sectors consider it a moral issue.

Advances in medical technology and research have allowed scientists to induce other cells to become pluripotent. This allows the production of pluripotent stem cells without using an embryo.

Treating Cancer With Killer T Cells Produced From Induced Pluripotent Stem Cells (iPS)

Japanese researchers at Riken have successfully created cells that will specifically attack cancer cells. These Killer T cells or lymphocytes were developed from induced pluripotent stem cells.

Stem Cells

Stem cells are cells that can differentiate (transform) into other type of cells, usually a higher form such as tissues and organs. There are specialized stem cells such as heart stem cells or blood stem cells that differentiates into specific type of cells.

Stem cells that can differentiate into other type of cells are called pluripotent stem cells. These are usually found in human embryos and what is generally known to the public as stem cells.

Scientists have recently discovered a method to convert an adult stem cell (whose differentiation is limited to certain types of tissues/organs) into a pluripotent stem cell. These are called Induced Pluripotent Stem Cell (iPS). iPS cells are special in that it circumvents the controversy on harvesting stem cells from human embryos.

Killer T Cells

White blood cells or leukocytes are cells used by the immune system in attacking foreign and harmful cells. A subgroup of leukocytes are lymphocytes or killer t-cells.

Killer T cells are responsible for identifying and attacking infected cells. But when it comes to cancer cells, killer t-cells are not as efficient in weeding out these harmful cells. For one, some cancer cells have a property that prevents if from being attacked by killer t-cells. Another is that, lymphocytes have a short life span that proves ineffective in a prolonged fight.

Engineering Patient Specific Articular Cartilage Tissues With Induced Pluripotent Stem Cells

Scientists used induced pluripotent stem cells (iPSCs) to produce and engineer cartilage that opens up new treatments and therapies for patients with damaged cartilage, cartilage injury, and osteoarthritis.

Since the introduction of stem cell technology, its manner of procurement has garnered much moral debate. Initially, stem cells are taken from human embryos about four or five days after fertilization.

Stem cells are pluripotent. This means that they have the ability to transform or differentiate into a higher form of cell, tissue or organ. It is this ability that scientists look to as the next evolution of medical science.

Nuclear Reprogramming And Its Role In Stem Cell Technology, Cell Pluripotency and DNA

British biologist, Sir John Betrand Gurdon, FRS, was awarded the Nobel Prize for Physiology or Medicine for the discovery that mature cells can be reprogrammed to become pluripotent (transform into any other type of cell).

This process is known as nuclear reprogramming and is at the forefront of stem cell technology.

A mature cell already has an established identity. Nuclear reprogramming wipes this information and transforms it to another kind of cell. It can open up new treatments and therapies for diseases and even repair and replace damaged tissues and organs.

Scientists Speed Up and Increase Efficiency In Production of Induced Pluripotent Stem Cells

Induced pluripotent stem cells generated using a kinase inhibitor.
Credit: Sanford-Burnham Medical Research Institute

To understand stem cells, there are two terms that are important to understand; pluripotency and differentiation.

Differentiation is the process in which the cell can transform itself into a higher class or specialized type of cell.

Pluripotency in stem cell biology means that the cell can differentiate itself into three types of germ layers: the endoderm, the mesoderm, and the ectoderm. The term "germ layer" more or less refers to the tissue layer. A group of germ layers eventually form tissues and organs of the body.

These three germ layers a stem cell can differentiate into, form much of the human body's organs. The endoderm forms into the internal organs such as the lungs, stomach lining, and the intestinal tract. The Mesoderm forms muscle and bone groups while the ectoderm forms epidermal tissues and the nervous system.

Because the stem cell can differentiate into other type of cells, there is much focus on this field for medical research. Stem cell research can open up new and effective treatments for otherwise difficult conditions such as alzheimers, parkinsons, cardiovascular diseases, and even cancer.

Early in stem cell research, a primary source for these type of cells were embryonic stem cells. These cells came from human fertilized eggs that are about four to five days old. Because of the manner of this process, there are moral issues that were raised with regards to these type of cells.

A recent technology introduced another way to source stem cells. These are called induced pluripotent stem cells or iPSC. These are artificially produced stem cells from non-pluripotent cells. The process is done by inducing or activating dormant genes within the cell to activate its pluripotency.

Making it easier to make stem cells

The process researchers use to generate induced pluripotent stem cells (iPSCs)—a special type of stem cell that can be made in the lab from any type of adult cell—is time consuming and inefficient. To speed things up, researchers at Sanford-Burnham Medical Research Institute (Sanford-Burnham) turned to kinase inhibitors. These chemical compounds block the activity of kinases, enzymes responsible for many aspects of cellular communication, survival, and growth. As they outline in a paper published September 25 in Nature Communications, the team found several kinase inhibitors that, when added to starter cells, help generate many more iPSCs than the standard method. This new capability will likely speed up research in many fields, better enabling scientists around the world to study human disease and develop new treatments.

"Generating iPSCs depends on the regulation of communication networks within cells," explained Tariq Rana, Ph.D., program director in Sanford-Burnham's Sanford Children's Health Research Center and senior author of the study. "So, when you start manipulating which genes are turned on or off in cells to create pluripotent stem cells, you are probably activating a large number of kinases. Since many of these active kinases are likely inhibiting the conversion to iPSCs, it made sense to us that adding inhibitors might lower the barrier."