Interaction With B-cells
To generate the follicular structures, FDCs need to be stimulated by lymphotoxin, a mediator produced by B cells. Also, noncognate B cells play a significant role as an antigen transporter to FDCs. They capture immune complexes in CR1/2-dependent way either directly from the blood or from macrophages, and putate to the lymphoid tissue, where they upload FDCs with opsonized antigen. FDCs, in turn, attract B cells with chemoattractant CXCL13. B cells lacking CXCR5, the receptor for CXCL13, still enter the white pulp, but are mislocalized and disorganized. The stimulation of CXCR5 on B cells upregulates LT production, which leads to FDCs activation and stimulates further CXCL13 secretion, thus generating a positive feed-forward loop. This results in the formation of GC, where antigen-activated B cells are trapped to undergo somatic mutation, positive and negative selection, isotype switching and differentiation into high-affinity plasma cells and memory B cells. The adhesion between FDCs and B cells is mediated by ICAM-1 (CD54)-LFA-1(CD11a) and VCAM-VLA-4 molecules. Activated B-cells with low affinity to antigen captured on FDCs surface as well as autoreactive B-cells undergo apoptosis, whereas B cells bound to FDCs through the antigen complex, survive due to apoptosis blockage caused by interaction with FDCs.
Read more about this topic: Follicular Dendritic Cells
Famous quotes containing the words interaction with and/or interaction:
“Recent studies that have investigated maternal satisfaction have found this to be a better prediction of mother-child interaction than work status alone. More important for the overall quality of interaction with their children than simply whether the mother works or not, these studies suggest, is how satisfied the mother is with her role as worker or homemaker. Satisfied women are consistently more warm, involved, playful, stimulating and effective with their children than unsatisfied women.”
—Alison Clarke-Stewart (20th century)
“The act of putting into your mouth what the earth has grown is perhaps your most direct interaction with the earth.”
—Frances Moore Lappé (b. 1944)