Comments on: The dark side of stem cell quiescence http://hematopoiesis.info/2010/08/01/the-dark-side-of-stem-cell-quiescence/ Blood Stem Cell & Cell Therapy Trends Fri, 20 Jan 2012 01:41:14 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Henry E. Young, PhD http://hematopoiesis.info/2010/08/01/the-dark-side-of-stem-cell-quiescence/#comment-15276 Henry E. Young, PhD Wed, 25 Aug 2010 13:28:36 +0000 http://hematopoiesis.info/?p=1480#comment-15276 We have isolated quiescent adult stem cells from the skeletal muscle of an amputaed limb of an 87 year old female who was a type-I diabetic since childhood. The quiescent 87 year old stem cells isolated, i.e., GL-MesoSCs., ELSCs, and BLSCs reacted idetically to similar stem cells isolated from newborn skeletal muscle in all aspects of culturing, characterization, and cryopreservation. It may be the particular niche that the stem cells are located, i.e., bone marrow versus skeletal muscle, and the type of stem cells isolated, i.e., HSCs versus GL-MesoSCs, ELSCs, and BLSCs, which may dictate the results described in the "dark side" article. Also, we have karyotyped freshly isolated and single cell serially diluted clones of GL-MesoSC as well as the identical clones that had undergone 690 population doublings (that is 2 to the 690th power - may beyond Hayflick's biological clock for human cells. We found the karyotypes to match identically. So again, I think one has to explore more the "dark side" of quiescent stem cells from all aspects and different venues before judgements can be made about their positive or negative abilities for use in regenerative medicine. We have isolated quiescent adult stem cells from the skeletal muscle of an amputaed limb of an 87 year old female who was a type-I diabetic since childhood. The quiescent 87 year old stem cells isolated, i.e., GL-MesoSCs., ELSCs, and BLSCs reacted idetically to similar stem cells isolated from newborn skeletal muscle in all aspects of culturing, characterization, and cryopreservation.

It may be the particular niche that the stem cells are located, i.e., bone marrow versus skeletal muscle, and the type of stem cells isolated, i.e., HSCs versus GL-MesoSCs, ELSCs, and BLSCs, which may dictate the results described in the “dark side” article.

Also, we have karyotyped freshly isolated and single cell serially diluted clones of GL-MesoSC as well as the identical clones that had undergone 690 population doublings (that is 2 to the 690th power – may beyond Hayflick’s biological clock for human cells. We found the karyotypes to match identically. So again, I think one has to explore more the “dark side” of quiescent stem cells from all aspects and different venues before judgements can be made about their positive or negative abilities for use in regenerative medicine.

]]>