BAFF induces spleen CD4+ T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression.
The TNF ligand family member "B cell-activating factor belonging to the TNF family" (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4(+) spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4(+) T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4(+) spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4(+) T cell proliferation.
Department of Orthodontics, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China.
Fang
F
Ji
Rongjing
R
Chen
Baojun
B
Liu
Xiaoping
X
Zhang
Junli
J
Han
Haining
H
Wang
Gang
G
Shen
Jiang
J
Tao
D000818:Animals; D053264:B-Cell Activating Factor / Q000494:pharmacology / Q000502:physiology*; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D049109:Cell Proliferation; D056742:Cyclin D2 / Q000096:biosynthesis*; D056743:Cyclin D3 / Q000096:biosynthesis*; D015536:Down-Regulation; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008813:Mice, Inbred ICR; D010766:Phosphorylation; D013154:Spleen / Q000276:immunology
D053264:B-Cell Activating Factor; D056742:Cyclin D2; D056743:Cyclin D3; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors; C474033:FoxO3 protein, mouse