Final answer:
T cells that are home to the skin express the Cutaneous Lymphocyte-Associated Antigen (CLA), which directs them to the site of infection or inflammation. This occurs during the process of T cell activation, clonal expansion, and differentiation into effector and memory T cells. The option (E) is correct.
Step-by-step explanation:
The question pertains to the changes in the homing behavior of T lymphocytes after their activation and the specific cell-surface molecules these cells express to direct them to specific sites in the body. Specifically, T cells homing to the skin express the Cutaneous Lymphocyte-Associated Antigen (CLA). This antigen plays a critical role in the migration of T cells to the skin during an immune response.
When T cells become activated by antigen-presenting cells (APCs), they undergo clonal expansion and differentiate into effector and memory T cells, with the help of cytokines. Effector T cells are short-lived and respond immediately to infection, whereas memory T cells are long-lived and can mount rapid responses upon subsequent exposures to the antigen. Therefore, option (E) is correct.
This question is not complete, Here I am attaching the complete question:
The full activation of T lymphocytes takes 4 to 5 days and is accompanied by marked changes in the homing behavior of these cells. Differential expression of cell-surface molecules can direct subsets of armed effector T cells to specific sites. Cells that home to the skin, for example, express what antigen?
(A) CEA
(B) AFP
(C) LTN
(D) MAGE
(E) CLA