系统性红斑狼疮患者外周血白细胞双链RNA依赖蛋白激酶基因表达

Peripheral blood leukocyte double strand RNA-dependent protein kinase gene expression in patients with systemic lupus erythematosus

目的通过检测系统性红斑狼疮（SLE）患者外周血白细胞双链RNA依赖蛋白激酶（PKR）基因表达水平，探讨其与SLE临床及病情活动的相关性。方法分离100例SLE患者、40例非SLE患者、40例健康人外周血白细胞，抽提总RNA并逆转录成cDNA，实时定量PCR检测所有受试者PKR基因表达水平，并进行相关性分析。以2-△Ct代表PKR mRNA的起始拷贝量。结果（1）SLE患者PKR mRNA起始拷贝量（14．69±7．62）高于非SLE患者（5．09±4．73；P=0．012）和健康人（4．79±3．49；P=0．005），差异有统计学意义。（2）SLE疾病活动指数（SLEDAI）≥15分的SLE患者PKR mRNA起始拷贝量为22．57±2.61，明显高于SLEDAI≤4分（8．85±2．17；P=0.000）和SLEDAI 5—14分的SLE患者（12．94±2．41；P=0．000）。（3）有狼疮肾炎的SLE患者PKR mRNA起始拷贝量（16．85±7．32）高于无狼疮肾炎的SLE患者（8．35±2．04；P=0．034）。（4）SLE患者PKR mRNA起始拷贝量与SLEDAI、外周血白细胞计数、24h尿蛋白、血清HDL—C呈正相关（r=0．32，P=0．000；r=0．46，P=0．000；r=0．21，P=0．000；r=0．21，P=0．022），与Hb、抗核糖核蛋白（RNP）抗体水平呈负相关（r=-0．22，P=0．035；k=-0．21，P=0．025）。结论SLE患者外周血白细胞PKR基因表达上调，且在重度SLE患者中更明显，提示PKR基因可能与狼疮的发病相关。

Objective To investigate the expression of the double-stranded RNA-dependent protein kinase （PKR） gene in the peripheral blood leukocyte of patients with systemic lupus erythematosus （SLE）, and to evaluate the relationship between the gene expression and the disease activity. Methods The clinical data of 100 SLE patients, 40 non-SLE patients with rheumatic diseases, and 40 normal controls were collected. Total RNA was extracted from the peripheral blood and then reverse transcribed into cDNA. Sybr green dye based real-time quantitative PCR method was used to compare the expression levels （indicated as 2 - △Ct value） of PKR in the three groups. Results （ 1 ） The 2 - △Ct value of PKR expression level in the SLE patients was （ 14. 69 ± 7. 62） , which was significantly higher than those in the non-SLE patients （5.09 ± 4. 73,P = 0. 012） and normal controls （4.79 ± 3.49, P = 0. 005 ）. （ 2 ） The 2 - △Ct value of PKR expression level in the SLE patients with severe activity was （22. 57 ± 2. 61 ） , which was significantly higher than those in the SLE patients with mild activity and no activity（ 12. 94 ± 2.41 ,P = 0. 000;8.85 ± 2. 17 ,P = 0. 000）. （ 3 ） The 2 - △Ct value of PKR expression level in the SLE patients with lupus nephritis was significantly higher than that in the SLE patients without lupus nephritis （ 16. 85 ± 7. 32 vs 8.35 ± 2. 04, P = 0. 034）. （4） The 2- △Ct value of PKR was correlated with the systemic lupus erythematosus index （SLEDAI） scores （r = 0. 32, P =0. 000）, WBC（r =0. 46,P =0. 000）, Hb（r = -0.22,P =0. 035）, the quantitation of urine protein in 24 hours （r =0. 21 ,P =0. 000）, HDL-C （r =0. 21 ,P =0. 022） ,and anti-RNP antibody （rs = -0. 21 ,P = 0. 025）. Conclusions The expression of PKR in the SLE patients is up-regulated, especially in those with severe activity. The expression level of PKR gene is associated with SLE disease activity.