以人B淋巴细胞株Raji、人早幼粒白血病细胞株HL60为底物检测抗细胞膜DNA抗体在系统性红斑狼疮中的诊断价值

Indirect immunofluorescence on human B iymphoma cell line Raji and promyelocytic line HL60 for detection of DNA-associated autoantibodies to cell membrane in systemic lupus erythematosus

目的比较以人B淋巴细胞株Raji、人早幼粒白血病细胞株HL60为底物检测抗细胞膜DNA抗体（抗cmONA抗体）在系统性红斑狼疮（SLE）中的诊断价值。方法分别以人B淋巴细胞株Raji、人早幼粒白血病细胞株HL60为底物，用间接免疫荧光法（IIF）检测306例SLE患者、192例疾病对照组患者、50例健康对照组血清中的抗cmDNA抗体。结果以人B淋巴细胞株Raji为底物检测抗cmDNA抗体在306例SLE患者中阳性率为72．5％。而在脊柱关节病、类风湿关节炎、原发干燥综合征和其他结缔组织病中的阳性率分别为5．8％、10．0％、13．3％、15．0％。以人早幼粒白血病细胞株HL60为底物检测抗cmDNA抗体在306例SLE患者中阳性率为76．1％。而在脊柱关节病、类风湿关肯炎、原发干燥综合征和其他结缔组织病中的阳性率分别为9．6％、11．1％、20．0％、22．5％。两种细胞为底物检测抗cmDNA抗体在健康对照组中阳性率均为0。抗cmDNA抗体阳性率在SLE组明硅高于疾病对照组及健康对照组（P〈0．01）。以Raji及HL60两种细胞株为底物检测SLE患者抗cmDNA抗体，敏感性分别为72．5％和76．1％，特异性分别为91．7％和86．8％，差异均无统计学意义（P〉0．05）。Raji及HL60细胞培养、冻存及复苏方法相似，但Raji细胞较HL60细胞更易复苏。在荧光显微镜下观察，Raji细胞比HL60细胞表达效果更好。结论抗cmDNA抗体是一种诊断阳性率较高的SLE血清学标记物之一。选择Raji细胞株为底物检测SIE患者的抗cmDNA抗体较HL60细胞株更有优势。

Objective To compare the significance of DNA-associated autoantibodies to cell mem- brane（cmDNA） in systemic lupus erythematosus（SLE） detected with indirect immunofluorescence on human B lymphoma cell line Raji and promyelocytic line HL60. Methods Indirect immunofluorescence assay both on cell line Raji and HI-60 was used to measure anti-cmDNA antibodies in sera of 306 SLE patients, 192 pa- tients with other rheumatic diseases and 50 healthy controls. Results Indirect immunofluorescence assay on cell line Raji was used to measure anti-cmDNA antibodies, 72.5% SLE and 10.4% other rheumatic diseases were positive for anti-cmDNA, but negative in 50 blood donors （ P 〈 0.01 ）. Indirect immunofluorescence assay on cell line HL60 was used to measure anti-cmDNA antibodies, 76.1% SLE and 16.7% other rheu- matic diseases were positive for anti-cmDNA, but negative in 50 blood donors（ P 〈 0.01 ）. The sensitivity of anti-cmDNA were 72. 5% and 76. 1%, respectively. The specificity of anti-cmDNA was 91. 7% and 86.8%, respectively. There was no significant difference in sensitivity and specificity （ P 〉 0.05 ）. The methods of culture, freeze and resuscitation on the two cells were similar, but cell line Raji was easier to re- suscitate than cell line HL60. Observing with fluorescence microscope, we find that cmDNA was expressed on the both cells and the staining was stronger on cell line Raji than HL60. Conclusion Anti-cmDNA antibody has high positivitv which is one of the most valuable marker in the diagnosis of SLE. We recommend to measure anti-cmDNA antibodies with indirect immunofluorescence assay on cell line Raji rather than HL60.