zellZellAdhäsion

Zelladhäsion, also known as cell adhesion, refers to the process by which cells interact and attach to one another or to the extracellular matrix. This biological phenomenon is fundamental for the formation and maintenance of tissues and organs in multicellular organisms. It plays a critical role in a wide range of cellular and physiological processes, including embryonic development, immune response, wound healing, and cell signaling.

The molecular mechanisms underlying cell adhesion involve specialized proteins on the cell surface called adhesion molecules. These molecules can mediate homophilic interactions, where similar molecules on adjacent cells bind to each other, or heterophilic interactions, where different molecules on opposing cells bind. Key families of adhesion molecules include cadherins, integrins, selectins, and the immunoglobulin superfamily. Cadherins are crucial for calcium-dependent cell-cell adhesion and are involved in maintaining tissue integrity. Integrins link the cell's internal cytoskeleton to the extracellular matrix, facilitating cell migration and signaling. Selectins are important in the initial, transient adhesion of leukocytes to endothelial cells during inflammation. Immunoglobulin superfamily members, such as ICAMs and NCAMs, participate in various cell-cell interactions, particularly in the immune system and nervous system.

Disruptions in cell adhesion can lead to various pathological conditions. For instance, defects in cadherin function are implicated in cancer metastasis, where cells detach from the primary tumor and spread to other parts of the body. Autoimmune diseases can arise from the immune system mistakenly attacking its own cell adhesion molecules. Understanding the intricate mechanisms of cell adhesion is vital for developing therapeutic strategies for a multitude of diseases.