摘要目的 探讨骨髓单个核细胞Coombs(BMMNC-Coombs)实验(+)血细胞减少症(又称免疫相关性血细胞减少症,IRP)患者骨髓"红系造血岛(EI)"的形成机制.方法 选取IRP患者48例、病例对照10例及正常对照11名为研究对象,采用流式细胞术(FCM)检测骨髓红系造血细胞自身抗体(BM-autoAb),免疫荧光(IF)法标记骨髓"EI",并分析其临床资料.结果 48例IRP患者中14例(29.17%)IF阳性,即"EI"中巨噬细胞和幼红细胞间沉积自身抗体IgG,且这14例患者BM-autoAb均为抗GlycoAIgG型(100%);均有贫血;胸骨骨髓增生程度大多呈活跃或明显活跃,红系比例为0.441±0.139,易见"EI"及红细胞吞噬现象;髂骨红系比例为0.248±0.204;血清总胆红素水平(TBIL)为(13.4±7.5)μmol/L,血清间接胆红素水平(IBIL)为(9.4±4.7)μmol/L.6个月总有效率85.7%.IF阴性组(34例),BM-autoAb抗GlycoAIgG型2例(5.89%);其中贫血31例(91.2%),无贫血3例(8.8%);网织红细胞(Ret)比例为(0.013±0.010);胸骨骨髓增生程度为活跃、明显活跃或低下,红系比例为0.298±0.082,髂骨红系比例为0.212±0.162;TBIL为(13.3±17.1)μmol/L;IBIL为(6.6±6.7)μmol/L;6个月总有效率61.3%.IF阳性组患者RBC、Hb、Ret、IBIL、胸骨红系比例及6个月总有效率与IF阴性组患者相比差异均有统计学意义(P值均＜0.05).结论 一些IRP患者骨髓涂片中所见部分"EI"中的幼红细胞和巨噬细胞是通过自身抗体IgG连结的,这些"EI"不是滋养骨髓红系的造血龛,而是巨噬细胞吞噬、破坏幼红细胞的原位标志.这部分IRP患者骨髓巨噬细胞通过其表面的IgGFc受体连接、吞噬及破坏覆有自身抗体IgG的幼红细胞,从而导致红系造血细胞破坏.

abstractsObjective To explore the mechanism of 'erythroblast island(EI) ' formation in the bone marrow of patients with immun-related hemocytopenia (IRP). Methods The category of BM-auto antibody (au Ab) in 48 patients with IRP was detected with FCM. The BM-au Ab in the ' EI' of these cases were explored with immuonhistofluorescence(IF). Clinical and laboratory characteristics of these cases were also analyzed retrospectively. Results IgG could be detected in the 'EI' on the BM smear of 14 cases(29.17% ),BM-au Ab mainly deposited at the edge/membranes between macrophage and erythroblasts rather than cyto plasm. Positive reaction were seen in all the cases with GlycoAlgG. The red blood cell count [ ( 1.8 ± 0.5 ) ×1012/L] and hemoglobin level [ (59.6 ± 16.2 ) g/L] were significantly lower than that in the IF( - ) group [ (2.5 ± 0.9) × l012/L and ( 83.4 ± 25. 0) g/L ] ( P ＜ 0. 05 ). The percentage of reticulocyte [ ( 2.0 ±0.8) % ], serum level of IBIL [ (9.4 ± 4.7) μmol/L ], percentage of erythroblats in sternum BM (0.441 ±0. 139) and response rate to therapy(85.7% ) in IF( + )group were significantly higher than that in IF( - )group [ ( 1.3 ± 1.0) %, (6.6 ± 6.7 ) μmol/L, 0. 298 ± 0.082, 61.3%, respectively ] ( P ＜ 0.05 ). Conclusion Macrophage was connected with erythroblasts through autologous IgG in the'EI' s of some patients with IRP. 'EI' were the places where macrophages devoured and destroyed erythroblasts rather than erythroid development and differentiation. The pathogenetic mechanism of IRP might be associated with macrophages phagocytosing and destroying BM hematopoietic cells.