The growth of organs outside the body cannot be separated from "mechanical stimulation"

In addition to chemical factors, mechanical influences also play an important role in the natural growth of human organs (such as kidneys, lungs and breasts), and also play an important role in the development of tumors

Organoids are three-dimensional systems that simulate various human organs

Scientists at the Technical University of Munich and the Ruhr University in Bochum used breast organoids to analyze the complex interactions between cells and surrounding tissues.

Integrated dynamic development process

The organoids developed by the research team formed branched ducts, the structure and organization of which are very similar to those of the human breast

"Starting from a single stem cell, these organoids formed a complex, branched three-dimensional structure composed of thousands of cells in just 14 days," said Andreas Bausch, professor of cell biophysics at the University of Munich and head of the research team.

The research team used a time-resolved microscope to observe the growth structure in a few days and successfully monitored the dynamic development process in detail

By expanding in the direction of movement and then contracting again, the cells generate a strong force to deform the surrounding collagen matrix, allowing the organoids to independently organize their own further growth direction

Stabilize the collagen "cage"

"This is due to the mechanical plasticity of collagen," said Benedikt Buchmann, the lead author of the research team

The result of the whole process is the formation of a mechanically stable collagen "cage", which eventually surrounds the growing branches

These findings provide a basis for using this model system to study more complex processes, such as the first step of metastasis or interaction with other cell types

Mechanical plasticity of collagen directs branch elongation in human mammary gland organoids

# # #