Which integrin is vital for gut homing by binding to MAdCAM?

The integrin vital for gut homing by binding to MAdCAM (Mucosal Addressin Cell Adhesion Molecule) is α4β7. This specific integrin plays a crucial role in the migration of lymphocytes to the gut-associated lymphoid tissues (GALT). The interaction between α4β7 and its ligand, MAdCAM, helps in the localization of these immune cells to the gastrointestinal tract, which is essential for maintaining gut health and immune function.

In the context of gut homing, lymphocytes express α4β7 integrin, which enables their adhesion to the endothelium of the intestinal vasculature where MAdCAM is expressed. This binding facilitates the entry of lymphocytes into the gut tissues, allowing them to participate in immune surveillance and response. The specificity of this mechanism highlights the importance of α4β7 in targeting the gut and maintaining mucosal immunity.

Other integrins mentioned do not primarily mediate gut homing. For example, β2-integrins are mainly involved in leukocyte adhesion and migration in various tissues but are not specific for migrating into the gut. Similarly, αLβ2, also known as LFA-1, plays a role in the immune response but does not specifically