Adhesion molecules

Definition

Adhesion molecules are proteins located on the cell surface that facilitate the binding of cells to each other and to the extracellular matrix. These molecules play a crucial role in various biological processes, including immune responses, tissue repair, and embryonic development, by promoting cell communication and stability in tissue structures.

5 Must Know Facts For Your Next Test

1. Adhesion molecules are essential for the immune system as they allow white blood cells to adhere to blood vessel walls during an inflammatory response, facilitating their movement to sites of infection or injury.
2. Different types of adhesion molecules, such as integrins and selectins, serve distinct functions in cell signaling and communication during immune responses.
3. The binding properties of adhesion molecules can be altered during disease processes, affecting cell migration and interactions which can contribute to inflammation and cancer metastasis.
4. Adhesion molecules not only help with immune cell trafficking but also play roles in wound healing by promoting the migration and organization of cells at injury sites.
5. Research on adhesion molecules has led to therapeutic targets for conditions like autoimmune diseases, where altered adhesion molecule function can lead to excessive inflammation.

Review Questions

• How do adhesion molecules contribute to the immune response during inflammation?
  • Adhesion molecules play a critical role in the immune response by enabling white blood cells to adhere to the endothelial cells lining blood vessels. This adhesion is essential for leukocyte extravasation, where immune cells exit circulation and migrate towards sites of infection or injury. The interaction between leukocytes and endothelial cells is mediated by specific adhesion molecules like selectins, allowing for effective immune surveillance and response.
• Discuss the different types of adhesion molecules and their specific functions in immune system activity.
  • There are several types of adhesion molecules including integrins, selectins, and cadherins, each with unique roles in immune system activity. Integrins facilitate strong adhesion between cells and the extracellular matrix, supporting cell signaling and migration. Selectins mediate transient interactions between leukocytes and vascular endothelium during inflammation. Cadherins are primarily involved in maintaining tissue structure through cell-cell adhesion. Together, these adhesion molecules orchestrate complex cellular interactions necessary for effective immune responses.
• Evaluate how dysfunction in adhesion molecules can impact disease processes such as inflammation or cancer.
  • Dysfunction in adhesion molecules can lead to significant impacts on disease processes. For instance, altered expression or function of selectins can result in impaired leukocyte recruitment during inflammation, potentially leading to chronic inflammatory conditions. In cancer, abnormal expression of integrins can enhance tumor cell migration and invasion, facilitating metastasis. Understanding these mechanisms opens avenues for targeted therapies that could correct these dysfunctions and improve disease outcomes.

Related terms

Integrins: Integrins are a type of adhesion molecule that connect the extracellular matrix to the cytoskeleton of cells, playing a key role in cell signaling and communication.

Selectins: Selectins are adhesion molecules that mediate the interaction between leukocytes and endothelial cells, playing a significant role in the immune response during inflammation.

Cadherins: Cadherins are a family of adhesion molecules essential for cell-cell adhesion, particularly in maintaining the structure and integrity of tissues.