Objective: To clarify the role of endothelial cells (ECs) injury induced by anti-endothelial cell antibody (AECA) in allogeneic hematopoietic stem cell transplantation (allo-HSCT).
Methods: Serum immunoglobulin (IgG) from allo-HSCT recipients were purified and incubated with human umbilical vein vascular endothelium (HUVEC) in vitro, then the functional changes and cell apoptosis were tested.
Results: After incubation with AECA positive IgG, soluble adhesion molecules significantly elevated in culture supernatant. When concentration of IgG was 160, 320, and 640 μg/ml, concentrations of soluble intercellular adhesion molecule-1 in supernatant were statistically higher in AECA positive groups [(117.10 ± 12.82) vs (78.17 ± 4.90) pg/ml, (151.30 ± 15.35) vs (89.46 ± 6.02) pg/ml, (239.00 ± 32.53) vs (127.80 ± 13.86) pg/ml, P<0.01)]. When concentration of IgG was 40, 80, 160, 320, and 640 μg/ml, concentrations of soluble vascular cell adhesion molecule-1 in supernatant were also statistically higher in AECA positive groups [(38.51 ± 3.76) vs (24.78 ± 2.59) pg/ml, (61.34 ± 6.99) vs (38.20 ± 3.17) pg/ml, (135.60 ± 24.46) vs (63.73 ± 5.08) pg/ml, (221.30 ± 29.40) vs (112.80 ± 8.91) pg/ml, (420.90 ± 31.70) vs (224.40 ± 20.79) pg/ml, P<0.01]. Clotting activity factors also elevated in culture supernatant after incubation with AECA positive IgG. When concentration of IgG was 80, 160, 320, and 640 μg/ml, concentrations of von Willebrand factor were statistically higher in AECA positive groups [(19.51 ± 0.72) vs (17.17 ± 0.60) ng/ml, P=0.0193; (22.97 ± 1.18) vs (18.27 ± 0.61) ng/ml, (26.40 ± 1.54) vs (19.53 ± 0.70) ng/ml, (34.35 ± 1.60) vs (23.81 ± 0.92) ng/ml, P<0.01]. When concentration of IgG was 320 and 640 μg/ml, concentrations of thrombomodulin were statistically higher in AECA positive groups [(57.50 ± 4.50) vs (40.31 ± 4.39) pg/ml, P=0.0132; (59.18 ± 4.11) vs (38.84 ± 5.16) pg/ml, P<0.01]. However, inflammatory factors (IL-1β, IL-6, IL-8 and ANG2) were not statistically different in AECA positive and negative groups (P>0.05). Moreover, IgG from AECA positive samples did not change the proliferation or cell apoptosis.
Conclusion: AECA from allo-HSCT recipients dysregulates ECs' function in vitro, but do not induce apoptosis, which is valuable in the pathophysiology of graft-versus-host disease (GVHD) and other complications after allo-HSCT.
目的: 探讨抗内皮细胞抗体（AECA）介导的血管内皮（EC）损伤在异基因造血干细胞移植（allo-HSCT）中的病理生理机制。
方法: 收集allo-HSCT后患者的血清并纯化IgG型免疫球蛋白，将后者与人脐静脉内皮细胞（HUVEC）共培养，观察HUVEC的功能变化及凋亡情况。
结果: HUVEC与AECA阳性的IgG共培养后，黏附分子表达显著增高：IgG浓度为160、320、640 µg/ml时，上清可溶性胞间黏附分子-1浓度分别为（117.10±12.82）对（78.17±4.90）pg/ml，（151.30±15.35）对（89.46±6.02）pg/ml，（239.00±32.53）对（127.8±13.86）pg/ml（P值均<0.01）；IgG浓度为40、80、160、320、640 µg/ml时，上清可溶性血管细胞黏附分子-1浓度分别为（38.51±3.762）对（24.78±2.50）pg/ml，（61.34±6.99）对（38.20±3.17）pg/ml，（135.60±24.46）对（63.73±5.08) pg/ml，（221.3±29.40）对（112.80±8.91) pg/ml，（420.90±31.70）对（224.40±20.79）pg/ml（P值均<0.01）。HUVEC与AECA阳性的IgG共培养后，凝血活性因子表达显著增高：IgG浓度为80、160、320、640 µg/ml时，上清血管性血友病因子浓度分别为（19.51±0.72）对（17.17± 0.60）ng/ml，（22.97±1.18）对（18.27±0.614）ng/ml，（26.40±1.54）对（19.53±0.701) ng/ml，（34.35±1.60）对（23.81±0.92）ng/ml（P值均<0.05）；IgG浓度为320、640 µg/ml时，上清血栓调节素浓度分别为（57.50± 4.50）对（40.31±4.39) pg/ml，（59.18±4.11）对（38.84±5.16）pg/ml（P值均<0.05）。AECA阳性IgG对HUVEC分泌炎性因子（IL-1β、IL-6、IL-8及ANG2）无明显作用（P>0.05）。此外，AECA并不诱导HUVEC凋亡，对细胞增殖亦无影响（P>0.05）。
结论: AECA能引起EC功能发生显著变化，并不引起细胞凋亡，对于阐明AECA介导的EC损伤在移植物抗宿主病等移植并发症中的作用机制有重要意义。