Development of membrane-like pre-stem cells after released from tube-shaped niches

We previously identified three distinct pre-stem cell lineages that further develop into blood CD34-positive stem cells, and mesenchymal stem cells. The pre-CD34-positive stem cells are spore-like, while the pre-mesenchymal stem cells are fusiform-shaped. All of them originate or released from tube-shaped tissue structures, or niches. In the current study, we present two membrane-like pre-stem progenitors. One of them had red thin membrane structures that were from disconnection of bamboo-like tissues and developed into thin membrane-like multi-nucleated cells. The other membrane-like structure had geometric-shape and was the place of developing numerous c-kit-positive stem cell progenitors. One geometric-shaped membrane could produce dozens to hundreds of progenitors in a synchronized pattern. Our findings provide more evidence that postnatal stem cells are unipotent and self-renewed in sealed tube-shaped structures. The tube-shaped structures released their inclusions that have distinct morphological differences among the cellular lineages. Thus, the self-renewal of each lineage-distinct stem cell has its unique pattern. Further, our data suggests that postnatal stem cells are renewed via a recurrent pattern. Our findings again challenged the old concepts of stem cell niche components, the origins of stem cell lineages and the self-renewal of stem cells.