In what situation would you expect increased cell adhesion molecule expression?

Increased cell adhesion molecule expression is commonly observed during tissue repair and inflammation because these processes require enhanced cell-to-cell and cell-to-extracellular matrix interactions. When tissues are damaged, the body responds by mobilizing immune cells to the site of injury, which rely on adhesion molecules to migrate from the bloodstream and bind to the damaged tissue.

Adhesion molecules, such as integrins and selectins, facilitate this process by allowing cells to adhere to one another and to the extracellular matrix, enhancing the effectiveness of the immune response. This increased expression helps in the recruitment of various types of cells, including leukocytes, to the site of inflammation or injury, ensuring that the tissue healing process can proceed effectively.

During normal cell growth, while there is some expression of adhesion molecules, it may not be significantly increased compared to the acute response needed for tissue repair. In apoptosis, as cells undergo programmed cell death, the focus is on detachment rather than adhesion, leading to decreased expression of these molecules. Likewise, during cell division, while adhesion is still necessary, the dynamics of adhesion might not change as dramatically as during repair and inflammation where immediate cellular interactions are crucial.