Yang Fan, Li Dongfeng, Xu Shuwen
Department of Neurology, Guangdong Institute for Geriatrics, Guangzhou, China.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2013 Mar;29(3):265-8.
To investigate the role of C5a in the release of TNF-α from microglial cells and its related mechanism, and identify the intervention effect of C5aR antagonist (C5aRA) in the pathological change of Alzheimer's disease (AD).
Soluble Aβ1-42 oligomer was prepared, identified by atomic force microscopy. Then Aβ1-42 oligomer alone, or in a combination with different levels of C5a, C5aRA, or C5a+C5aRA was used to treat cultured BV2 cells. The non-treated BV2 cells served as controls. ELISA was used to detect the concentration of TNF-α, and flow cytometry to analyze the expression of C5a receptor (CD88).
Aβ1-42 oligomer significantly stimulated BV2 cells to release TNF-α and CD88, compared to the control group (P<0.05 and P<0.01, respectively). C5a further increased the release of TNF-α (P<0.05 vs Aβ1-42 group). In contrast, C5aRA inhibited remarkably the release of TNF-α stimulated by Aβ1-42 (P<0.01). Nevertheless, C5a or C5aRA didn't show a significant effect on the expression of CD88 in BV2 cells that was elevated by Aβ1-42 treatment (P>0.05).
C5a promotes the release of TNF-α from microglial cells; Aβ1-42 can further boost the release and C5aRA can inhibite TNF-α secretion of microglial cells significantly.
探讨C5a在小胶质细胞释放肿瘤坏死因子-α（TNF-α）中的作用及其相关机制，明确C5a受体拮抗剂（C5aRA）对阿尔茨海默病（AD）病理变化的干预作用。
制备可溶性Aβ1-42寡聚体，采用原子力显微镜进行鉴定。然后用单独的Aβ1-42寡聚体，或与不同水平的C5a、C5aRA，或C5a + C5aRA联合使用，处理培养的BV2细胞。未处理的BV2细胞作为对照。采用酶联免疫吸附测定（ELISA）检测TNF-α浓度，用流式细胞术分析C5a受体（CD88）的表达。
与对照组相比，Aβ1-42寡聚体显著刺激BV2细胞释放TNF-α和CD88（分别为P<0.05和P<0.01）。C5a进一步增加了TNF-α的释放（与Aβ1-42组相比，P<0.05）。相反，C5aRA显著抑制Aβ1-42刺激的TNF-α释放（P<0.01）。然而，C5a或C5aRA对Aβ1-42处理后BV2细胞中CD88的表达没有显著影响（P>0.05）。
C5a促进小胶质细胞释放TNF-α；Aβ1-42可进一步增强其释放，而C5aRA可显著抑制小胶质细胞TNF-α的分泌。
