337 replies to this topic

[Mind]

Drug combination could speed healing (or regeneration?)

Research by Dr Sara Rankin and colleagues at Imperial College London suggests that it is possible to increase the numbers of these types of stem cells by using a combination of factors. They treated mice with a growth factor combined with the drug Mozobil, results showed that the mice released as many as 100-times more endothelial and mesenchymal stem cells than untreated mice.

The researchers hope that clinical trials of the therapy will be possible within the next ten years, and conclude that their findings “can be exploited to provide efficacious stem cell therapy for tissue regeneration.”

10 years! Man these things take forever.

[Mind]

Bone Marrow Stem Cells Used To Regenerate Skin

This article/study and the previous one hammers home to me the importance of signaling factors in making stem cells into the magical therapies they were supposed to be a decade ago. Just injecting stem cells into damaged tissue and expecting regeneration is a fools errand.

To investigate the practicability of repairing burn wounds with tissue-engineered skin combined with bone marrow stem cells, the study established a burn wound model in the skin of pigs, which is known to be anatomically and physiologically similar to human skin.

Engineering technology and biomedical theory methods were used to make artificial skin with natural materials and bone marrow derived stem cells. Once the artificial skin was attached to the patient and the dermal layer had begun to regenerate, stem cells were differentiated into skin cells. The cells are self-renewing and raise the quality of healing in wound healing therapy. When grafted to the burn wounds, the engineered skin containing stem cells showed better healing, less wound contraction and better development of blood vessels.

[Anthony]

http://www.timesonli...icle5569645.ece

http://www.thisisms....article245.html

http://www.anti-agin....com/63stem.php

If this stem cell technique allows (and we won't know for years) paralyzed patients to regrow neurons and Schwann cells, do you think they'll try it in the brain next?

Anthony

[DJS]

http://www.scienceda...90326141547.htm

Stem Cell Research: New Way To Make Stem Cells Avoids Risk Of Cancer

ScienceDaily (Mar. 29, 2009) — Scientists at the University of Wisconsin-Madison have found a way to endow human skin cells with embryonic stem cell-like properties without inserting potentially problematic new genes into their DNA.

The team of researchers reports that it has created induced human pluripotent stem (iPS) cells completely free of viral vectors and exotic genes.

By reprogramming skin cells to an embryonic state using a plasmid rather than a virus to ferry reprogramming genes into adult cells, the Wisconsin group's work removes a key safety concern about the potential use of iPS cells in therapeutic settings.

[AaronCW]

Hello everyone,

I'm doing some reading on HSCT (Hematopoietic stem cell transplantation) and am wondering if anyone has come across any recent advances made in this technique. Any other info would also be appreciated.

Thanks,
Aaron

[Mind]

This breakthrough produced a lot of headlines claiming "Stem Cell Breakthrough" (kind-of erroneous). It is potentially much more powerful because it involves a stem cell growth factor. One thing I learned at UABBA was that just inserting stem cells into the body and expecting miraculous results has been found to be a fool's errand. Stem cells respond to the environment they are in. Putting "young" stem cells into old tissue just causes the stem cells to "get old and die" (for lack of a better scientific way to describe it). What is needed is knowledge about what factors, what chemical signals, cause stem cells to grow and do the work of repairing damaged or worn out tissue. Teriparatide, mentioned in the article, might be one of those factors.

Slow-Healing Bones May Get Boost From Drug

Researchers at the University of Rochester Medical Center in New York gave teriparatide (Forteo) to 145 people who had bone fractures that had not healed, many for six months or more. They found that 93 percent of them showed significant healing and pain control after eight to 12 weeks.

Teriparatide speeds the healing of fractures by changing the behavior and number of cartilage and bone stem cells involved in the healing process, the researchers found.

"The decreased healing time is significant, especially when fractures are in hard-to-heal areas like the pelvis and the spine, where you can't easily immobilize the bone -- and stop the pain," Dr. Susan V. Bukata, medical director of the university's Center for Bone Health, said in a news release from the center.

"Typically, a pelvic fracture will take months to heal, and people are in extreme pain for the first eight to 12 weeks," she said. "This time was more than cut in half. We saw complete pain relief, callus formation and stability of the fracture in people who had fractures that up to that point had not healed."

Based on the findings, the news release said, the U.S. National Institutes of Health has funded a clinical trial of the drug's use on fractures. The study will include men and post-menopausal women older than 50 who have what's called a low-energy pelvic fracture and who are admitted to the emergency department of Strong Memorial Hospital in Rochester.

[caston]

This breakthrough produced a lot of headlines claiming "Stem Cell Breakthrough" (kind-of erroneous). It is potentially much more powerful because it involves a stem cell growth factor. One thing I learned at UABBA was that just inserting stem cells into the body and expecting miraculous results has been found to be a fool's errand. Stem cells respond to the environment they are in. Putting "young" stem cells into old tissue just causes the stem cells to "get old and die" (for lack of a better scientific way to describe it). What is needed is knowledge about what factors, what chemical signals, cause stem cells to grow and do the work of repairing damaged or worn out tissue. Teriparatide, mentioned in the article, might be one of those factors.

Not only that but stems cells will likely be attacked by T cells. Even autologus stem cells can be targets for them if they have changed ever so slightly.

Also take into consideration the existing tissue is likely to be highly diseased. The chronic intracellular bacteria will simply and quite happily infect these new stem cells.

This is highly speculatory but all the things we may well do in the lab to prepare good stem cells the body may be capable of doing itself under the right conditions. For example cells may fuse with each other to repair cellular components, telemeres and nuclear DNA but will only do so if they are not going to give them a bad case of pathogenic intracelluar bacteria.

Edited by caston, 23 April 2009 - 03:31 PM.

[Mind]

Adult muscle stem cells in mice do not use the same regenerative genes as embryonic muscle stem cells.

This is an important finding if it is similar in humans. It might represent another hurdle for using embryonic stem cells for treatment. Of course, the flip side is that adult bodies (adult stem cells) might have more capabilities than we are aware of.

As Christoph explained: "The paired-box genes, Pax3 and Pax7 are involved in the development of the skeletal muscles. It is well established that both genes are needed to produce muscle stem cells in the embryo. A previous student, Alice Chen, studied how these genes are turned on in embryonic muscle stem cells (also published in Nature). I thought that if they are so important in the embryo, they must be important for adult muscle stem cells. Using genetic tricks, I was able to suppress both genes in the adult muscle stem cells. I was totally surprised to find that the muscle stem cells are normal without them."

The researchers then looked at whether the same was true upon injury, after which the repair process requires muscle stem cells to make new muscles. For this, they injured the leg muscles between the knee and ankle. They were again surprised that these muscle stem cells, without the two key embryonic muscle stem cell genes, could generate muscles as well as normal muscle stem cells. They even performed a second round of injury and found that the stem cells were still active.

The scientists then wondered when these genes become unnecessary for muscle stem cells to regenerate muscles. It turned out that these embryonic genes are important to muscle stem cell creation up to the first three weeks after birth. What makes the muscle stem cells different after three weeks? The scientist believe that these two embryonic muscle stem cell genes also tell the stem cells to become quiet as the organism matures. After that time is reached, they "hand over" their jobs to a different set of genes. The researchers suggest that since the adult muscle stem cells are only activated when injury occurs (by trauma or exercise), they use a new set of genes from those used during embryonic development, which proceeds without injury. The scientists are eager to find these adult muscle stem cell genes.