A conspicuous role for B cells In Sjögren's syndrome.
Although the relative contributions of T cells and B cells in Sjögren's syndrome (SS) are far from being settled, recent studies have suggested a crucial role for B cells in its pathophysiology. Early investigations have focused on the ability of B cells to produce autoantibodies, and new studies have enlarged the range of their functions. For example, beyond the paradigm that T lymphocytes maintain strict control over B cells, the latter cells are now acknowledged to solicit their own help from the former cells and release a flurry of cytokines. Further, some of these B cells act as antigen-presenting cells. Increased levels of the B cell activating factor (BAFF) found in SS may be responsible for high numbers of circulating Bm2/Bm2' cells and associated functional abnormalities of B cells, such as a BAFF-induced increased expression of CD19, which decreases the required strength generated by antigen binding for transmitting its signal. This review reports compelling evidence that B cells are involved in the pathophysiology of SS. As this brings novel prospects for the treatment of the disease, it is no surprise that B cell ablative treatment has proven to be relatively efficacious in SS.
Youinou
Pierre
P
Department of Immunopathology, Brest University Medical School, Brest, France. youinou@univ-brest.fr
Devauchelle
Valérie
V
Hutin
Pascal
P
Le Berre
Rozenn
R
Saraux
Alain
A
Pers
Jacques-Olivier
JO
D001323:Autoantibodies / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology*; D006801:Humans; D012859:Sjogren's Syndrome / Q000276:immunology*
D001323:Autoantibodies