Stem Cells Show Potential for Treatment of Some Lung Diseases

Stem Cells Show Potential for Treatment of Some Lung Diseases

Researchers in Korea have transplanted mesenchymal stem cells from umbilical cord blood into the respiratory system of animals whose lungs were damaged. They found that the cells started to repair part of the damaged lungs. They were assimilated into the organ and differentiated into lung tissue. The story is reported in the Korea Times. No significant further details, and one of the researchers “cautioned that it was too early to say whether the animal tests are conclusive or if human tests would have the same results.”

This is obviously promising, but still a long way from human therapies. I presume that some kinds of lung injury/disease would be more amenable to this kind of treatment than others.

Skin Cells Difficult to Grow from Embryonic Stem Cells

Skin Cells Difficult to Grow from Embryonic Stem Cells

According to an article in Scientific American, researchers at Harvard have had several struggles in attempts to get embryonic stem cells to differentiate into skin cells (keratinocytes) in culture. Most cells did not differentiate, and those that did grew poorly. When the researchers added genetic material from the human papillomavirus (the virus responsible for cervical cancer), the stem cells grew well but still did not differentiate in the way that normal skin cells do.

The article suggests that embryonic stem cell research is still highly challenging. After having read some of the other recent studies that have come out, though, I find myself curious about the culture mediums that were used and what the application of the right growth factors would do. It’s starting to seem like a lot of factors influence stem cell differentiation, and a failure in one place does not mean a failure in all. The only way to find out will be to keep trying.

Multiple Scientific Papers on Extracellular Matrix Factors

Multiple Scientific Papers on Extracellular Matrix Factors

A press release from the publishers of Stem Cells and Development describes several articles that appear in the December issue and may be of interest to researchers. The articles focus on different conditions for stem cell growth in culture. One study found that elements normally found in bone--such as laminin-1, fibronectin, and collagen-1--have a defining effect on the differentiation of bone marrow progenitor cells. Other papers report on the influence of different growth factors on stem cell differentiation. Taken together, the papers support the conclusion that the matrix upon which the stem cell resides is important in how the cell differentiates. An important point is that the matrix itself becomes altered as the stem cells differentiate, which in turn affects stem cell behavior, making the process a continuously evolving one.

Mad Cow Disease Has Relation To Stem Cells

Mad Cow Disease Has Relation To Stem Cells

All right, that’s a bit of a sensationalist headline. But it turns out that the protein which causes neurodegenerative disorders such as “mad cow disease” (bovine spongiform encephalopathy) is important for maintaining stem cells. Researchers have wondered why mammals continue to produce the prion protein, which can lead to fatal brain lesions when it changes its shape. (Other forms of the disease are scrapie in sheep and Creutzfeld-Jakob disease in people.) After discovering that the prion protein was expressed abundantly on the surface of all hematopoietic stem cells, researchers tried to find out what it did. The scientists at the Whitehead Institute for Biomedical Research studied mice who had had the prion protein “knocked out” and performed a relay-like series of bone marrow transplants from one mouse group to another. Eventually the scientists ended up with a group of mice whose stem cells were unable to generate new cells. When successive transplants were done with mice who had the prion protein, the stem cells still worked fully many transplants down the line.

The story is reported on Newswise.

More on Sickle-Cell Anemia

More on Sickle-Cell Anemia

I blogged on January 10 about some research done at UCSF but didn’t have as many details as I would have liked. An article published yesterday on Pacific News Service reports that mouse blastocysts had the abnormal hemoglobin S replaced with normal hemoglobin A, and they grew into hematopoietic stem cells in culture. However, they have not yet been transplanted back into mice, so it is unknown if the body will accept the new cells.

Stem Cells Located on Edges of Bone Marrow

Stem Cells Located on Edges of Bone Marrow

In a new study which might make bone marrow transplants easier, scientists at the University of Michigan Medical School and University of Tsukuba in Japan have discovered that stem cells are not clustered in bone marrow, as previously thought, but instead are located alongside bone-forming cells at the edge of the marrow. The researchers spliced a fluorescent protein gene from jellyfish into blood stem cell genes in mice and were able to locate them under a microscope. It might be possible to expand the stem cells within the niche of the bone prior to harvesting, instead of needing to remove the entire bone marrow to separate the stem cells as is presently done. The story is reported on Reuters. (The article also covers a second study, which I will blog separately.) A press release on EurekAlert says that this finding should also make it easier to study how hematopoietic (blood-producing) stem cells work in their natural environment. When they are removed, they either die or begin differentiating, so important information about how they function is lost when they are studied in the lab.