Max Planck Institute for Molecular Biomedicine

Lifelong vascular growth drives increase of blood cell production

A new method can be used to predict how a cancer will progress

New long-term microscopy method shows differences to long bones

Low EphB4 and high ephrin B2 levels activate the arterial programme in the vascular cells

Artificial transcription factor reprograms cells of human and different animal species with high efficiency

Skin cells, liver cells, neural cells – the human body is made up of various different cell types. Hans Schöler and his team at the Max Planck Institute for Molecular Biomedicine in Muenster have successfully turned these specialists back into generalists that are capable of cell division. These are able to produce different types of cells, and to develop into organ-like structures, for example into so-called brain organoids. The scientists use these to study basic processes in the human brain and the formation of diseases such as Parkinson’s.

The loss of bone mass is an important aspect of ageing and can cause a disease called osteoporosis. Research results show that blood vessels play a central role in the formation and maintenance of bone mass. While some blood vessels promote the formation of new bone, others regulate the balance between bone-forming and bone-degrading cells. Blood vessels in the skeletal system and their function change fundamentally with increasing age.

Atherosclerosis is a degenerative disease of the vessel wall. In leaky regions of the endothelial cell layer of arteries, lipid particles enter the vessel wall and trigger plaque formation. This happens preferentially in regions where curvature and vessel junctions slow down the blood stream and cause turbulences whereas in long and straight regions, rapid and laminar blood flow protect against leaks. We have found a mechanism that explains how rapid laminar flow protects against endothelial leaks. The molecular basis of this mechanism revealed potential targets for reducing atherosclerosis.

The successful application of synthetic materials for tissue engineering and regeneration depends on the ingrowth of blood vessels from the surrounding host tissue. In order to determine the required materials parameters, we have developed the first cell culture model that mimics the natural process of blood vessel formation in a synthetic tissue environment with independently tunable parameters.

Early stages of mammalian embryos are able to enter a naturally occurring dormant state (diapause) to slow their development during unfavorable environmental conditions. Surprisingly, we found that these seemingly “sleeping” embryos exhibit dynamic cell-cell communication and shape-shifting tissue architecture during stasis, which is required to maintain their long-term developmental potential.

The overexpression of four specific transcription factors allows for reprogramming of somatic cells into induced pluripotent stem cells (iPSCs), which can give rise to all cell types of the adult body. We found that overexpression of one of these factors,  Oct4, causes epigenetic changes that deteriorate the quality of the resultant iPSCs. Excluding Oct4 from the reprogramming cocktail leads to iPSCs with unprecedented developmental potential.