Follicular dendritic cells (FDCs) are cells of the immune system found in primary and secondary lymph follicles of the B cell areas of the lymphoid tissue. These cells were first described in 1965 and, although they have a very dendritic morphology, are not dendritic cells (DCs). Unlike DCs, FDCs are not derived from the bone-marrow hematopoetic stem cell, but are of mesenchymal origin.