Zhang Feng, Song Shan-Shan, Shu Jin-Ling, Li Ying, Wu Yu-Jing, Wang Qing-Tong, Chen Jing-Yu, Chang Yan, Wu Hua-Xun, Zhang Ling-Ling, Wei Wei
Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-inflammatory and Immune Medicine (Anhui Medical University), Ministry of Education, Hefei 230032, China.
Acta Pharmacol Sin. 2016 Aug;37(8):1101-9. doi: 10.1038/aps.2016.15. Epub 2016 May 16.
B cell-activating factor belonging to the TNF family (BAFF) is a member of TNF family and required for peripheral B cell survival and homeostasis. BAFF has been shown to promote the proliferation of T and B cells. In this study we examined whether and how BAFF mediated the interaction between mouse T and B cells in vitro.
BAFF-stimulated B or T cells were co-cultured with T or B cells. The interactions between T and B cells were analyzed by measuring the expression of co-stimulatory molecules (CD28/CD80 or CD40/CD154), the proliferation and secretion of T and B cells and other factors. Two siRNAs against the transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and BAFF receptor (BAFF-R) were used to identify the receptors responsible for the actions of BAFF.
BAFF-stimulated B cells significantly promoted the proliferation and activity of co-cultured T cells, and increased the percentages of CD4(+)CD28(+) and CD4(+)CD154(+) T cells. Similarly, BAFF-stimulated T cells significantly promoted the proliferation and activity of co-cultured B cells, and increased CD19(+)CD80(+) and CD19(+)CD40(+)B cell subpopulations. BAFF-R siRNA-silenced B cells showed significantly lower expression of CD40 and CD80 than the control B cells. When the BAFF-R siRNA-silenced B cells were stimulated with BAFF, then co-cultured with T cells, the expression of CD28 and CD154 on T cells was not increased. TACI siRNA-silenced B cells exhibited higher expression of CD40 and CD80 than the control B cells. When the TACI siRNA-silenced B cells were stimulated with BAFF, then co-cultured with T cells, the expression of CD28 and CD154 on T cells was significantly increased.
BAFF upregulates CD28/B7 and CD40/CD154 expression, and promotes the interactions between T and B cells in a BAFF-R-dependent manner.
肿瘤坏死因子家族成员B细胞活化因子（BAFF）是外周B细胞存活和稳态所必需的。研究表明，BAFF可促进T细胞和B细胞的增殖。在本研究中，我们检测了BAFF在体外是否以及如何介导小鼠T细胞和B细胞之间的相互作用。
将经BAFF刺激的B细胞或T细胞与T细胞或B细胞共培养。通过检测共刺激分子（CD28/CD80或CD40/CD154）的表达、T细胞和B细胞的增殖及分泌情况以及其他因子，分析T细胞和B细胞之间的相互作用。使用两种针对跨膜激活剂、钙调蛋白和环孢素配体相互作用分子（TACI）以及BAFF受体（BAFF-R）的小干扰RNA（siRNA）来鉴定介导BAFF作用的受体。
经BAFF刺激的B细胞显著促进了共培养T细胞的增殖和活性，并增加了CD4(+)CD28(+)和CD4(+)CD154(+) T细胞的百分比。同样，经BAFF刺激的T细胞显著促进了共培养B细胞的增殖和活性，并增加了CD19(+)CD80(+)和CD19(+)CD40(+) B细胞亚群。与对照B细胞相比，经BAFF-R siRNA沉默的B细胞中CD40和CD80的表达显著降低。当用BAFF刺激经BAFF-R siRNA沉默的B细胞，然后与T细胞共培养时，T细胞上CD28和CD154的表达并未增加。与对照B细胞相比，经TACI siRNA沉默的B细胞中CD40和CD80的表达更高。当用BAFF刺激经TACI siRNA沉默的B细胞，然后与T细胞共培养时,T细胞上CD28和CD154的表达显著增加。
BAFF上调CD28/B7和CD40/CD154的表达，并以BAFF-R依赖的方式促进T细胞和B细胞之间的相互作用。
