TNF deficiency fails to protect BAFF transgenic mice against autoimmunity and reveals a predisposition to B cell lymphoma.
TNF is well characterized as a mediator of inflammatory responses. TNF also facilitates organization of secondary lymphoid organs, particularly B cell follicles and germinal centers, a hallmark of T-dependent Ab responses. TNF also mediates defense against tumors. We examined the role of TNF in the development of inflammatory autoimmune disorders resembling systemic lupus erythematosus and Sjögren's syndrome induced by excess B cell-activating factor belonging to the TNF family (BAFF), by generating BAFF-transgenic (Tg) mice lacking TNF. TNF(-/-) BAFF-Tg mice resembled TNF(-/-) mice, in that they lacked B cell follicles, follicular dendritic cells, and germinal centers, and have impaired responses to T-dependent Ags. Nevertheless, TNF(-/-) BAFF-Tg mice developed autoimmune disorders similar to that of BAFF-Tg mice. Disease in TNF(-/-) BAFF-Tg mice correlates with the expansion of transitional type 2 and marginal zone B cell populations and enhanced T-independent immune responses. TNF deficiency in BAFF-Tg mice also led to a surprisingly high incidence of B cell lymphomas (>35%), which most likely resulted from the combined effects of BAFF promotion of neoplastic B cell survival, coupled with lack of protective antitumor defense by TNF. Thus, TNF appears to be dispensable for BAFF-mediated autoimmune disorders and may, in fact, counter any proneoplastic effects of high levels of BAFF in diseases such as Sjögren's syndrome, systemic lupus erythematosus, and rheumatoid arthritis.
Batten
Marcel
M
Department of Arthritis and Inflammation, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, New South Wales 2010, Australia.
Fletcher
Carrie
C
Ng
Lai Guan
LG
Groom
Joanna
J
Wheway
Julie
J
Laâbi
Yacine
Y
Xin
Xiaoguan
X
Schneider
Pascal
P
Tschopp
Jurg
J
Mackay
Charles R
CR
Mackay
Fabienne
F
D000818:Animals; D000955:Antigens, T-Independent / Q000502:physiology; D001323:Autoantibodies / Q000096:biosynthesis; D053264:B-Cell Activating Factor; D016175:B-Lymphocyte Subsets / Q000378:metabolism / Q000473:pathology; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D020022:Genetic Predisposition to Disease; D005921:Glomerulonephritis / Q000235:genetics / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000235:genetics* / Q000276:immunology / Q000517:prevention & control; D008223:Lymphoma / Q000235:genetics / Q000276:immunology; D016393:Lymphoma, B-Cell / Q000235:genetics* / Q000276:immunology*; D008565:Membrane Proteins / Q000235:genetics* / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D012859:Sjogren's Syndrome / Q000235:genetics / Q000276:immunology; D013163:Splenomegaly / Q000235:genetics / Q000276:immunology / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000172:deficiency* / Q000235:genetics* / Q000502:physiology; D015854:Up-Regulation / Q000235:genetics / Q000276:immunology
D000955:Antigens, T-Independent; D001323:Autoantibodies; D053264:B-Cell Activating Factor; D008565:Membrane Proteins; C505720:Tnfsf13b protein, mouse; D014409:Tumor Necrosis Factor-alpha