Blood Group Reference Laboratory, Shanghai Blood Center, Hongqiao Road 1191, Shanghai, 200051, China.
School of Life Science, East China Normal University, Shanghai, China.
Inflammation. 2018 Aug;41(4):1361-1371. doi: 10.1007/s10753-018-0784-9.
The NLR family pyrin domain-containing protein 3 (NLRP3) inflammasome is triggered by various stimuli. Whether the NLRP3 inflammasome is activated during the monocyte clearing of aged or damaged erythrocytes is unknown. This work aimed to determine whether the NLRP3 inflammasome is activated during the THP-1 cell engulfing of aged erythrocytes. In the study, THP-1 cells were treated with PMA and then coincubated with untreated red blood cells (RBCs), 42 °C-treated RBCs, immunoglobulin G (IgG) anti-D-sensitized RBCs, Rhnull/Rhmod RBC sample, hemoglobin, and RBC ghost. The activation of the NLRP3 inflammasome and production of some proinflammatory cytokines were determined using immunoblotting, cytometric bead array, and digital PCR. An NLRP3 inflammasome inhibitor was also used to evaluate the alteration of the NLRP3 activation and RBC clearance rate. The untreated RBCs, 42 °C-incubated RBCs, IgG-opsonized RBCs, Rhnull/Rhmod RBCs, RBC ghosts, and hemoglobin induced the THP-1-cell-mediated activation of the NLRP3 inflammasome and the production of inflammatory cytokines. The RBC clearance rate exhibited a positive correlation with the expression of proinflammatory cytokines. The NLRP3 inflammasome inhibitor reduced the NLRP3 activation and RBC phagocytosis rate. The NLRP3 inflammasome was activated during the clearance of the aged erythrocytes through unopsonized and opsonized pathways. However, the mechanism of such phenomenon needs to be further elucidated. Such mechanism may provide new insight into the assessment of the safety of transfusing long-storage RBC based on cytokine levels.
NLR 家族包含 pyrin 结构域的蛋白 3（NLRP3）炎性小体可被多种刺激物激活。目前尚不清楚衰老或受损红细胞清除过程中是否会激活 NLRP3 炎性小体。本研究旨在确定 THP-1 细胞吞噬衰老红细胞过程中是否会激活 NLRP3 炎性小体。在该研究中，先用 PMA 处理 THP-1 细胞，然后与未经处理的红细胞（RBC）、42℃孵育的 RBC、IgG 抗-D 致敏的 RBC、Rhnull/Rhmod RBC 样本、血红蛋白和 RBC 影细胞共孵育。采用免疫印迹、流式细胞术和数字 PCR 测定 NLRP3 炎性小体的激活和某些促炎细胞因子的产生。还使用 NLRP3 炎性小体抑制剂评估 NLRP3 激活和 RBC 清除率的变化。未经处理的 RBC、42℃孵育的 RBC、IgG 调理的 RBC、Rhnull/Rhmod RBC、RBC 影细胞和血红蛋白均可诱导 THP-1 细胞介导的 NLRP3 炎性小体激活和炎症细胞因子的产生。RBC 清除率与促炎细胞因子的表达呈正相关。NLRP3 炎性小体抑制剂降低了 NLRP3 的激活和 RBC 的吞噬率。未调理和调理的途径均可通过清除衰老的红细胞激活 NLRP3 炎性小体。然而，这种现象的机制尚需进一步阐明。这种机制可能为基于细胞因子水平评估长期储存 RBC 输血安全性提供新的见解。
