Massachusetts State Board Esthetics Practice Exam

What is the role of Langerhans cells in the epidermis?

1. Producing keratin

2. Protecting against infection

3. Storing lipids

4. Facilitiating cell division

The correct answer is: Protecting against infection

Langerhans cells play a crucial role in the immune system within the epidermis, primarily by protecting against infection. These specialized dendritic cells act as sentinel immune cells, monitoring the skin for invading pathogens, such as bacteria and viruses. When they detect harmful substances, Langerhans cells capture and process these antigens, then migrate to lymph nodes to present them to other immune cells, which triggers a systemic immune response. This function is vital for maintaining the skin's barrier and preventing infections, making it clear why protecting against infection is the correct choice in this context. In contrast, producing keratin is primarily the function of keratinocytes, which are the main cell type in the epidermis. Storing lipids is associated with other cell types, particularly adipocytes in the subcutaneous layer. Facilitating cell division is more related to basal layer stem cells that are responsible for the regeneration of the epidermis. Each of these processes plays a role in skin health, but Langerhans cells are specifically focused on immune protection.