[Characteristic and function of peripheral blood mononuclear cells-induced macrophages in patients with myelodysplastic syndrome]

目的

观察骨髓增生异常综合征（MDS）患者单个核细胞诱导的巨噬细胞的功能，分析其与MDS疾病发展的关系。

方法

以2014年9月至2015年12月天津医科大学总医院血液科24例MDS患者为病例组，以15名健康志愿者为正常对照组。收集外周血标本并分离单个核细胞，体外以GM-CSF诱导分化形成巨噬细胞。在光学显微镜下观察巨噬细胞的形态；使用流式细胞术检测巨噬细胞的数量及其表面受体CD206、SIRPα的表达水平；分别采用流式细胞术和免疫荧光显微镜检测巨噬细胞的吞噬功能。

结果

①MDS来源的巨噬细胞形态较正常对照差（形态不规则、细胞体积小、异形明显、无足突、数量减少），MDS外周血单个核细胞转化为巨噬细胞的转化率为（5.17±3.47）%，显著低于正常对照组的（66.18±13.43）%（t=3.529，P=0.001）；②MDS来源的巨噬细胞表面识别受体CD206的表达水平[（9.73±2.59）%]显著低于正常对照组[（51.15±10.82）%]（t=4.551，P<0.001），SIRPα的表达水平[（0.51±0.09）%]显著低于正常对照组[（0.77±0.06）%]（t=2.102，P=0.043）；③MDS来源的巨噬细胞吞噬免疫微球的吞噬指数、吞噬百分率分别为0.45±0.08、（23.69±3.22）%，显著低于正常对照组的0.92±0.07、（42.75±2.13）%（P值均<0.05），MDS来源的巨噬细胞吞噬单个核细胞的吞噬指数（0.24±0.04）显著低于正常对照组（0.48±0.96，t=3.464，P=0.001）。

结论

MDS患者外周血单个核细胞诱导形成巨噬细胞能力下降，吞噬识别受体减少，吞噬能力减弱。

[Quantities and function of NK cells in patients with positive BMMNC-Coombs test and cytopenia]

OBJECTIVE

To test NK cell quantities and function in patients with positive BMMNC-Coombs test (CBCPC) and cytopenia and to explore how NK cell participate in the progress of this disease.

METHODS

The percentage of CD3(-)CD56(+) NK cell in peripheral blood lymphocytes, the expression of activating receptor (NKG2D, NKp46, NKp44), inhibitory receptor (CD158a, CD158b), perforin and granzyme-β were detected by flow cytometry. All samples were taken from 42 patients (22 newly diagnosed and 20 in remission) and 12 healthy volunteers. The correlation between the above parameters and patients' clinical profile were evaluated.

RESULTS

①The percentage of CD3(-)CD56(+) NK cell in new diagnosed and remission CBCPC patients were significantly lower than that in healthy control [(10.04 ± 5.33)% vs (19.94 ± 7.38)%; (11.62 ± 6.80)% vs (19.94 ± 7.38)%, all P<0.01]. ② The expression of activating receptor NKG2D in new diagnosed CBCPC patients was significantly higher than that in remission group and healthy control [(74.03±18.24)% vs (45.97±29.45)%; (74.03±18.24)% vs (41.89± 15.34)% , P <0.01]. ③The expression of inhibitory receptor CD158a in new diagnosed CBCPC patients was significantly lower than that in remission group and healthy control (median: 3.72% vs 16.10%, P= 0.015; 3.72% vs 11.04%, P=0.025). ④The expression of perforin in new diagnosed and remitted CBCPC patients were significantly higher than that in healthy controls [(75.71±10.14) % vs (57.20±18.85)%, P= 0.018; (77.88±22.82)% vs (57.20±18.85)%, P=0.008]. ⑤The product of NK cell percentage and perforin expression in new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.68±4.54)% vs (12.13±5.19)%, P=0.011; (8.24±5.80)% vs (12.13±5.19)%, P=0.023]. The product of NK cell percentage and granzyme-β expression in the new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.83±5.26)% vs (14.79±8.37)%, P=0.008; (8.37 ± 6.83)% vs (14.79±8.37)%, P=0.012].

CONCLUSION

Deceased quantities and impaired total NK function might play a role in pathogenesis of CBCPC.

Fas/FasL in the immune pathogenesis of severe aplastic anemia

Fas/FasL protein expression of bone marrow hematopoietic cells was investigated in severe aplastic anemia (SAA) patients. Fas expression was evaluated in CD34(+), GlycoA(+), CD33(+), and CD14(+) cells labeled with monoclonal antibodies in newly diagnosed and remission SAA patients along with normal controls. FasL expression was evaluated in CD8(+) cells in the same manner. In CD34(+) cells, Fas expression was significantly higher in the newly diagnosed SAA group (46.59 ± 27.60%) than the remission (6.12 ± 3.35%; P < 0.01) and control (8.89 ± 7.28%; P < 0.01) groups. In CD14(+), CD33(+), and GlycoA(+) cells, Fas levels were significantly lower in the newly diagnosed SAA group (29.29 ± 9.23, 46.88 ± 14.30, and 15.15 ± 9.26%, respectively) than in the remission (47.23 ± 31.56, 67.22 ± 34.68, and 43.56 ± 26.85%, respectively; P < 0.05) and normal control (51.25 ± 38.36, 72.06 ± 39.88, 50.38 ± 39.88%, respectively; P < 0.05) groups. FasL expression of CD8(+) cells was significantly higher in the newly diagnosed SAA group (89.53 ± 45.68%) than the remission (56.39 ± 27.94%; P < 0.01) and control (48.63 ± 27.38%; P <0.01) groups. No significant differences were observed between the remission and control groups. FasL expression in CD8(+) T cells was significantly higher in newly diagnosed patients, and CD34(+), CD33(+), CD14(+), and GlycoA(+) cells all showed Fas antigen expression. The Fas/FasL pathway might play an important role in excessive hematopoietic cell apoptosis in SAA bone marrow. Furthermore, CD34(+) cells are likely the main targets of SAA immune injury.