Follicular Dendritic Cells (FDCs)

FDCmicroenvironment
This graphic illustrates a small part of the micro-environment formed by the FDCs [REF] in the network in close association with lymphocytes (B cells and a few T cells). This microenvironment is a dynamic environment. Lymphocytes move around and mature. FDCs mature from FDC types with long and filiform (string-like) dendrites to those with beaded dendrites which help form "iccosomes" [immune complex coated bodies (=somes)] [REF]. As a result of interaction with FDC retained Ag and with specific T cells, B lymphocytes start maturing into plasma cells and memory B cells in this microenvironment. This process leads to the production of high affinity antibody in the anamnestic humoral immune response. For a more detailed discussion of this microenvironment refer to
this source.

Scanning Electron Micrograph View:

FDCuncoiled
In this scanning electron micrograph the isolated FDC shown retained its configuration typical of FDCs in situ. Note the major processes which end in a frayed configuration showing the typical club-shaped ends of the component dendrites.
(See also the figure below.)

Transmission Electron Micrograph:

TransmissionEM-FDC
A transmission electron micrograph showing the arrangement of the cell processes (arrow heads). The cell body has two euchromatic nuclei. The braided cell processes made up of fiament-like dendrites surround many lymphocytes. The white rectangle is shown enlarged in the upper left. Note the club shaped end of a dendrite.
(See the figure above.)

Home