What is the function of Langerhans cells in the immune system?

• A. Producing antibodies
• B. Collecting and presenting foreign substances to lymphocytes
• C. Secreting hormones
• D. Destroying pathogens

Answer: (B)

Langerhans cells play a critical role in the immune system as antigen-presenting cells. They are primarily found in the skin and mucosal tissues and are responsible for detecting foreign substances, such as pathogens and allergens. Once these cells encounter such substances, they process and present them on their surface using major histocompatibility complex (MHC) molecules. This presentation is vital for the activation of lymphocytes, specifically T cells, which are key players in the adaptive immune response. By facilitating this interaction between the innate and adaptive immune systems, Langerhans cells help the body mount an appropriate response to infections and other foreign invaders, making their role invaluable in maintaining the overall function of the immune system.