Final answer:
The most important β1 integrin on leukocytes that is induced by T-cell activation is known as VLA-4. It plays a significant role in mediating cell adhesion, essential for the immune response and tissue repair. The option (B) is correct.
Step-by-step explanation:
The most important member of the β1 integrin subfamily on leukocytes, which is induced by T cell activation, is called VLA-4 (Very Late Antigen-4). Integrins are crucial for cell adhesion as they are heterodimeric transmembrane receptors that bind to proteins within the extracellular matrix (ECM) such as fibronectin, laminin, and various collagens.
They mediate not only cell-cell interactions but also cell-extracellular matrix interactions, facilitating processes like tissue repair, immune response, and cell migration. VLA-4 specifically recognizes fibronectin as well as vascular cell adhesion molecule 1 (VCAM-1), which is found on endothelial cells, and is essential for leukocyte extravasation during the inflammatory response. Therefore, option (B) is correct.
This question is not complete, Here I am attaching the complete question:
Leukocyte adhesion is of pivotal importance in leukocyte physiology. If leukocytes cannot adhere to other leukocytes or various target cells, B-lymphocytes cannot synthesize immunoglobulins, T cells and NK cells are not cytotoxic, and neutrophils show no phagocytosis or chemotaxis. One family of adhesion molecules is the integrins. Integrins are αβ-heterodimers that recognize extracellular matrix and cell surface glycoproteins, as well as some soluble molecules such as complement factor C3bi. The most important member of the β1 integrin subfamily on leukocytes is one that is induced by T cell activation. What is it called?
(A) Mac-1
(B) VLA-4
(C) ICAM-1
(D) ICAM-2
(E) ICAM-3