Which cells found in the Stratum Spinosum react to antigens that cross broken skin?

Langerhans' cells are specialized immune cells located in the Stratum Spinosum of the epidermis. Their primary function is to act as antigen-presenting cells, which means they play a crucial role in the immune response, especially when the skin barrier is compromised. When antigens enter through broken skin, Langerhans' cells can capture these foreign substances, process them, and present them to T cells in the lymph nodes, thereby initiating an immune response.

This immune surveillance is particularly important for protecting the body from infections and other harmful agents that could penetrate the skin barrier. In contrast, basal cells are primarily responsible for generating new skin cells, keratinocytes are the predominant cell type that forms the outermost layer of the skin and is involved in producing keratin, and melanocytes are responsible for producing melanin, the pigment that gives skin its color and protects against UV radiation. While all these cell types play important roles in skin health and function, it is Langerhans' cells that are specifically involved in the detection and response to antigens that breach the skin’s surface.