Follicular dendritic cells (FDC) are primarily responsible for what function?

Follicular dendritic cells (FDC) play a crucial role in the immune system, particularly within the germinal centers of lymphoid tissues, such as lymph nodes and the spleen. Their primary function is to capture and hold intact antigens, which are crucial for B cell activation and differentiation. FDC have a unique morphology and surface markers that allow them to efficiently present antigens to B cells, facilitating these cells' maturation and the generation of high-affinity antibodies.

By retaining these intact antigens, FDC provide a localized environment that promotes the interaction between B cells and the antigens. This interaction is essential for the development of a robust immune response and contributes to the formation of memory B cells, which provide long-term immunity. The physical presence of such antigens is important for the processes of affinity maturation and somatic hypermutation, key aspects of the adaptive immune response.

In contrast, functions attributed to the other choices, like antibody secretion or regulating T-cell activation, are performed by other immune cells, such as plasma cells for antibody secretion and various other cells, including dendritic cells and macrophages, for T-cell regulation. Thus, the unique role of FDC in holding intact antigens enhances their significance in the adaptive immune response