Navigation Links
Stem cell expansion

Transplantation of hematopoietic stem cells (HSCs, the cells that can give rise to all blood and most immune cell types) can save patients whose own hematopoietic system is defective or has been destroyed (often through radiation or chemotherapy of cancer). HSCs are very rare, and it is often hard to obtain enough of them for a successful transplant. To overcome this limitation, Hans-Peter Kiem and colleagues have developed a way to expand HSCs in the laboratory prior to transplantation.

As they report in the international open-access journal PLoS Medicine, expression of a gene called HOXB4 can instruct stem cells to divide and make more stem cells. When the researchers tested those expanded cell populations in monkeys that had received a lethal dose of radiation, they found that they were better at reconstituting the monkeys' immune and blood systems.

HSCs are found in small numbers in the bone marrow, the peripheral blood, and in cord blood, which is harvested from the umbilical cord at birth. Cord blood is increasingly being used for transplantation, but the low number of HSCs present in a unit of cord blood means that transplanted cells can be slow to establish themselves (or engraft) in an adult recipient, prolonging the time the patient is susceptible to infections. Consequently, researchers are looking for ways to expand HSCs prior to transplantation. HOXB4 is known to be involved in stem cell maintenance and had shown some promise for stem cell expansion in mice. To investigate the potential of HOXB4 treatment for HSC expansion before transplantation in humans, Kiem and colleagues therefore turned to nonhuman primates, an established preclinical model for HSC transplantation and gene therapy.

The team showed that HOXB4 over-expression in populations of cells enriched for stem cells (i.e. those that are used for transplantation) for 6-9 days prior to transplantation greatly improved their subsequent engraftment in monkeys whose hema topoietic system had been destroyed through radiation. These results suggest that HOXB4-mediated expansion of stem cells could accelerate the engraftment of HSCs from sources that contain limited numbers of stem cells, such as cord blood. This was a proof-of-principle study that used small numbers of monkeys. Given the encouraging results, additional experiments are now planned to further test whether HOXB4 can eventually be used to improve the expansion and engraftment of stem cells in patients whose hematopoietic system has failed.

Kiem and colleagues achieved HOXB4 overexpression through introducing an active copy of the gene into the cells. However, because HOXB4 protein is available in recombinant form (i.e. produced in cell culture, much like human insulin), it should be possible to treat HSCs directly with the protein, avoiding the potential problems associated with genetic manipulation of the cells. As the reviewers of the article commented, such "clean expansion" of HSCs holds great potential for application in human transplant recipients.


Source:Public Library of Science

Related biology news :

1. A link is found between morphine addiction and the tendency to explore
2. Controversial drug shown to act on brain protein to cut alcohol use
3. Mouse brain cells rapidly recover after Alzheimers plaques are cleared
4. Mouse brain tumors mimic those in human genetic disorder
5. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
6. First atlas of key brain genes could speed research on cancer, neurological diseases
7. NYU study reveals how brains immune system fights viral encephalitis
8. Stem cells from brain transformed to produce insulin at Stanford
9. Birds brains reveal source of songs
10. Loves all in the brain: fMRI study shows strong, lateralized reward, not sex, drive
11. Revolutionary nanotechnology illuminates brain cells at work
Post Your Comments:

(Date:11/9/2015)... 09, 2015 ... the "Global Law Enforcement Biometrics Market ... --> ) has announced the ... Biometrics Market 2015-2019" report to their ... ( ) has announced the addition ...
(Date:10/29/2015)... 29, 2015   MedNet Solutions , an innovative ... of clinical research, is pleased to announce that it ... (MHTA) as one of only three finalists for a ... Small and Growing" category. The Tekne Awards honor ... superior technology innovation and leadership. iMedNet™ ...
(Date:10/29/2015)... 29, 2015  Connected health pioneer, Joseph C. ... of technology-enabled health and wellness, and the business opportunities ... The Internet of Healthy Things . Long ... even existed, Dr. Kvedar, vice president, Connected Health, Partners ... delivery, moving care from the hospital or doctor,s office ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... ... 2015 , ... A long-standing partnership between the Academy of ... formalized with the signing of a Memorandum of Understanding. , AMA Executive Director ... Minter and Capt. Albert Glenn Tuesday, November 24, 2015, at AMA Headquarters in ...
(Date:11/25/2015)... , November 25, 2015 ... Report is a professional and in-depth study on ...      (Logo: ) , ... the industry including definitions, classifications, applications and industry ... for the international markets including development trends, competitive ...
(Date:11/24/2015)... , Nov. 24, 2015  Asia-Pacific (APAC) ... research organisation (CRO) market. The trend of outsourcing ... lower margins but higher volume share for the ... and scale, however, margins in the CRO industry ... (CRO) Market ( ), finds that ...
(Date:11/24/2015)... 2015 Cepheid (NASDAQ: CPHD ) today ... following conference, and invited investors to participate via webcast. ...      Tuesday, December 1, 2015 at 11.00 a.m. Eastern Time ...      Tuesday, December 1, 2015 at 11.00 a.m. Eastern Time ... New York, NY      Tuesday, December 1, 2015 ...
Breaking Biology Technology: