Glowing spirals: Chemical scaffolds guide living cells into precisely defined three-dimensional patterns: Concentration gradients not only can guide bacteria, fungi, and amoebae; they are also very important in the early stages of embryogenesis because the development of seed leaves (cotyledon) is controlled through concentration gradients of messenger molecules. Three-dimensional chemical patterns play a role in many physiological and pathological processes, including the growth of blood vessels, regulation of blood pressure and heart rate, and tumor metastasis. Our immune cells also follow concentration gradients to find the spot where they are needed.
In order to examine these processes more closely, scientists want to imitate such chemical gradients in vitro. Making a three-dimensional chemical pattern and maintaining it long enough is not so easy.