Summarize this content to 2000 words in 6 paragraphs The lymphatic system plays a key role in maintaining the body’s fluid balance and supporting immune defences. Lymphatic vessels are composed of a single layer of endothelial cells, allowing the transfer of fluids, cells and large molecules from surrounding tissues into the vessels. These vessels must be highly permeable to efficiently absorb and transport fluid, while also being flexible enough to withstand sudden changes in tissue fluid volume, such as swelling, without rupture.
Shape-shifting cells
In a study published in the journal Nature, a research group led by Professor Taija Mäkinen, Director at the Wihuri Research Institute, investigated how the thin layer of endothelial cells maintains its integrity under varying fluid pressure conditions. The study found that the key factor is the ability of the cells to continuously change their unique shape.
“It’s long been known that the endothelial cells of lymphatic vessels resemble oak leaves or jigsaw puzzle pieces. The reason for this peculiar shape has, however, remained a mystery, and researchers have previously been unable to replicate it in cultured cells,” says Mäkinen.
A similar jigsaw puzzle-like shape can be seen in a completely different type of cell: on the surface of plant leaves. In plants, this pattern helps cells withstand internal fluid pressure, which is vital for plant growth and structural support.
The fact that jigsaw puzzle-like cells function similarly in both plants and mammals points to a fundamental biological principle: for organisms of various types, this distinctive cell shape enhances structural stability. The same principle has been applied in human-led design as well: for example, paving stones on roads are frequently arranged in undulating or interlocking patterns to improve durability and wear resistance.
