cells-molecules-rna-9.html
Medicon Valley_dec-jan
10 / 16
annual review 13-14 / december-january / p10 why
stem
cell
s
need to stick with their friends by eleanor cowie scientists at university of copenhagen and university of edinburgh have identifi ed a core set of functionally relevant factors which regulates embryonic
stem
cell
s
’ ability for self-renewal. a key aspect is the protein oct4 and how it makes
stem
cell
s
stick together. the identifi cation of these factors will be an important tool in devising better and safer ways of making specialised
cell
s
for future regenerative
cell
therapies for treatment of diseases like diabetes and parkinson’s disease. the results have been published in the scientifi c journal current biology scientists have known that the protein oct4 plays a key role in maintai- ning the embryonic
stem
cell
s
in pure form by turning on
stem
cell
genes, however up until now it has not been know which of the 8.000 or more possible genes that oct4 can choose from actually support self-renewal. by comparing the evolution of
stem
cell
s
in frogs, mice and humans, scientists at the danish
stem
cell
center (dan
stem
) and the mrc centre for regenerative medicine in edinburgh have now been able to link the protein oct4 with the ability of
cell
s
to stick together. they found that for embryonic
stem
cell
s
to thrive they need to stick together and oct4’s role is to make sure they stay that way. - embryonic
stem
cell
s
can stay forever young unless they become grown-up
cell
s
with a specialised job in a process called differentia- tion. our study shows that oct4 prevents this process by pushing
stem
cell
s
to stick to each other, says dr alessandra livigni, research fellow at the university of edinburgh. identifi cation of specifi c genes the research teams in edinburgh and copenhagen successfully identifi ed 53 genes, out of more than 8.000 possible candidates that together with oct4, functionally regulate
cell
adhesion. almost like fi nding needles in a haystack the scientists have paved the way for a more effi cient way of maintaining
stem
cell
s
as
stem
cell
s
. - embryonic
stem
cell
s
are characterized, among other things, by their ability to perpetuate themselves indefi nitely and differentiate into all the
cell
types in the body – a trait called pluripotency. though to be able to use them medically, we need to be able to maintain them as
stem
cell
s
, until they’re needed. when we want to turn a
stem
cell
into a specifi c
cell
for example; an insulin producing beta
cell
, or a nerve
cell
like those in the brain, we’d like this process to occur accurately and effi ciently. we cannot do this if we don’t understand how to maintain
stem
cell
s
as
stem
cell
s
, says professor joshua brickman from dan
stem
, university of copenhagen. future potential as well as maintaining embryonic
stem
cell
s
in their pure state more effectively, this new insight will also enable scientists to more effi ciently manipulate adult
cell
s
to revert to a
stem
cell
like stage known as induced pluripotent
stem
cell
s
(ips
cell
s
). these
cell
s
have many of the same traits and characteristics as embryonic
stem
cell
s
but can be derived from the patients to both help study degenerative disease and eventually treat them. - this research knowledge has the potential for us to change the way we grow
stem
cell
s
, enabling us to use them in a less costly and more effi cient way. it will help us devise better and safer ways to create specialised
cell
s
for future regenerative medicine therapies, concludes professor joshua brickman. read the scientifi c article in current biology: www.
cell
.com/ current-biology/abstract/s0960-9822(13)01195-0 study shows therapeutic potential of fat-derived
stem
cell
s
declines as donor’s age rises by sharon lee a new study released in
stem
cell
s
translational medicine demonstrates that the therapeutic value of
stem
cell
s
collected from fat declines when the
cell
s
come from older patients - this could restrict the effectiveness of autologous
cell
therapy using fat, or adipose-derived mesenchymal stromal
cell
s
(adscs), and require that we test
cell
material before use and develop ways to pretreat adscs from aged patients to enhance their therapeutic potential, said anastasia efi menko, m.d., ph.d. she and nina dzhoyashvili, m.d., were fi rst authors of the study led by yelena parfyonova, m.d., d.sc., at lomonosov moscow state university, moscow. cardiovascular disease remains the most common cause of death in most countries. mesenchymal stromal
cell
s
(mscs),
stem
cell
s
collected from either bone marrow or adipose tissue, are considered one of the most promising therapeutic agents for regenerating damaged tissue because of their proliferation potential and ability to be coaxed into different
cell
types. importantly, they also have the ability to stimulate the growth of new blood vessels, a process known as angiogenesis. the typical patient adipose tissue in particular is considered an ideal source for mscs because it is largely dispensable and the
stem
cell
s
are easily accessible in large amounts using a minimally invasive procedure. adscs have been used in several clinical trials looking at
cell
therapy for heart conditions, but most of the studies employed
cell
s
taken from relatively healthy young donors rather than sick, older ones — the typical patient when it comes to heart disease. -we knew that aging and disease itself may negatively affect msc activities, dr. dzhoyashvili said: - so the aim of our study was to investigate how patient age affects the properties of adscs, with special emphasis on their ability to stimulate angiogenesis. the results provide new insight the team analyzed age-associated changes in adscs collected from patients of different age groups, including some with coronary artery disease and some without. the results showed that adscs from the older patients in both groups expressed various age markers, including shorter telomeres, and, thus, confi rmed that adscs did age. telome- res, the regions of repetitive dna at the end of a chromosome, protect it from deterioration. - we showed that adscs from older patients both with and without coronary artery disease produced signifi cantly less amounts of angioge- nesis-stimulating factors compared with the younger patients in the study and their angiogenic capabilities lessened. the results provide new insight into molecular mechanisms underlying the age-related decline of
stem
cell
s
’ therapeutic potential, dr. efi menko concluded. - these fi ndings are signifi cant because the successful development of
cell
therapies depends on a thorough understanding of how age may affect the regenerative potential of autologous
cell
s
, said anthony atala, m.d., editor of
stem
cell
s
translational medicine and director of the wake forest institute for regenerative medicine. the full article, “adipose-derived stromal
cell
s
(adsc) from aged patients with coronary artery disease keep msc properties but exhibit characteristics of aging and have an impaired angiogenic potential,” can be accessed at: www.
stem
cell
s
tm.com. read the scientifi c article in current biology: www.
cell
.com/ current-biology/abstract/s0960-9822(13)01195-0 embryonic
stem
cell
s
stick together (green, left image) while they express oct4 protein in their nuclei (magenta, left). when oct4 is removed their shape changes and their adhesion to each other is reduced (right panel, nuclei in blue)
cobis-p011-11.html