Immortal cells
Progenitor cells are trapped in an endless self-renewal
Nanonews Network based on the materials of the Morgridge Institute for Research:
Morgridge scientists find way to ‘keep the lights on’ for cell self-renewalOne of the remarkable properties of pluripotent stem cells is their immortality, that is, the ability, under the right conditions, to divide and grow indefinitely.
It turns out that not only stem cells are endowed with this ability, but also their descendants, who have already advanced along the path of development: the property of proliferating without losing their identity is inherent in the so-called progenitor cells – a kind of workhorse responsible for the formation of specific tissues.
A group of scientists from the Morgridge Research Institute, led by James Thomson, a pioneer in the study of stem cells, has found a way to make mouse progenitor cells responsible for the formation of blood and vascular tissue practically immortal. By regulating a small number of genes, scientists drove these cells into a "trap" of self-renewal and made them capable of producing functional blood cells and blood vessels.
The results of this work, which will be published in the journal Stem Cell Reports, suggest the possibility of a new approach to obtaining cells in the laboratory for use in therapy, drug screening and as a tool in basic research.
"The most significant result for me is the ability to stop the development of these cells," says David Vereide, PhD, a specialist in regenerative biology, lead author of the publication. "As a rule, cells stay in this state for a very short time and are used during differentiation into specific cell types, but we found a way to intervene in the situation."
Blood and vascular cells are thought to originate from progenitor cells called hemangioblasts. In this research project, six transcription factors (proteins regulating gene expression) were identified and tested, which allowed hemangioblasts to continue proliferation without changing their identity for many generations.
Progenitor cells, "sons and daughters" of stem cells, giving rise to specific tissues, are, as a rule, the final stage of the process of formation of key building blocks of the body – brain cells, blood vessels, bones, etc. The method developed by Dr. Vereide and his colleagues will significantly increase the efficiency of obtaining cell types that have scientific and therapeutic value.
Embryonic stem cells are far from functional cell types, Vereide explains. Differentiating, for example, into a muscle or neuron, they go through many stages over several weeks or months, and each stage reduces the effectiveness of this process and increases the likelihood of mutations.
Cultured progenitor cells eliminate the need to go through all these stages.
"We are much closer to a functional cell type that may have medical significance," Vereide continues. "Instead of 20 stages, you need to go through one or two. If a certain number of these steps can be discarded, cell-based strategies become much more promising."
According to Vereide, the results of this study are "proof of concept", which consists in the fact that a state close to immortality is not the prerogative of stem cells. In the near future, researchers will move on to work with human stem cells and obtain progenitor cells that can potentially be used in various clinical applications.
Dr. Vereide is confident that this principle can be proven on other types of cells. With a deeper study of the condition preceding any tissue, it is possible to find key factors that will stimulate the proliferation of progenitor cells in a Petri dish, the scientist believes.
Portal "Eternal youth" http://vechnayamolodost.ru24.11.2014