葡萄糖-6-磷酸异构酶在诊断类风湿关节炎中的意义

The diagnostic relevance of glucose-6-phosphate isomerase in patients with rheumatoid arthritis

目的探讨类风湿关节炎（HA）患者外周血单个核细胞（PBMC）中葡萄糖-6-磷酸异构酶（GPI）mRNA及血清中GPI抗原表达与HA发病机制及活动性的关系，分析比较GPI与抗突变型瓜氨酸波形蛋白（MCV）抗体、抗环瓜氨酸多肽（CCP）抗体、类风湿因子（RF）在HA诊断中的价值。方法用实时荧光定量逆转录（FQ-RT）-PCR检测60例RA患者（活动期28例、缓解期32例）、30例其他风湿性疾病患者、30名健康体检者PBMC中GPI mRNA的表达水平和含量[以△Ct：Ct1（待测基因）-Ct2（内参基因）来比较基因表达水平的高低]；同时用ELISA检测各组血清中GPI和抗MCV抗体，抗CCP抗体和RF水平。结果HA患者GPI mRNA表达水平[△Ct=4．21（3．04—7．23）]明显高于其他风湿性疾病组[△Ct=8．42（5．16～9．98），P〈0．01]和健康对照组[△Ct=8．66（4．90—10．01），P〈0．01]，活动期组GPI mRNA表达水平[△Ct=3．78（1．28～6．09）]与缓解期组[△Ct=5．88（3．23～8．94）]的差异有统计学意义（H=11．760，P〈0．01）；HA组血清GPI水平[3．02（2．02—8．39）mg／L]明显高于其他风湿性疾病组[0．20（0．11～0．32）mg／L]和健康对照组[0．18（0．08～0．30）mg／L]，且RA活动期组血清GPI水平[4．84（2．81～10．38）mg／L]与缓解期组[2．12（1．26—4．34）mg／L]差异也有统计学意义（H=9．830，P〈0．01）。同时检测GPI、抗MCV抗体和抗CCP抗体对HA的敏感度分别为68％（41／60）、57％（34／60）、58％（35／60）；特异度分别为95％（57／60）、92％（55／60）、93％（56／60）。结论GPI mRNA可能参与了HA的发病过程，并与疾病的活动性相关，血清中GPI对HA诊断有相对较高的敏感度和特异度，可作为临床诊断HA的辅助指标。

Objective To assess the levels of glucose-6-phosphate isomerase （GPI） mRNA in peripheral blood monocytes and serum GPI levels in patients with rheumatoid arthritis, and analyze the association of serum GPI with MCV antibody, CCP antibody and RF of RA. Methods Fluorogenic quantitative real-time polymerase chain reaction （FQ-RT-PCR） was used to examine mRNA expression on peripheral blood monocytes in 60 RA patients （28 case in active stage,32 cases in stable stage） ,30 patients with other rheumatic diseases,and 30 healthy controls. ELISA was used to detect the levels of serum GPI, anti-MCV antibodies, anti-CCP antibodies and RF in each group. Results The levels of GPI mRNA in RA group [ △Ct = 4. 21 （3.04 -7. 23 ）] were significantly higher than those in patients with other rheumatic diseases [ △Ct = 8.42 （5. 16 - 9.98 ）, P 〈 0. 01 ] and healthy controls [ △Ct = 8.66 （4. 90 - 10. 01 ）, P 〈 0.01 ]. There were statistically significant differences of GPI mRNA levels between active RA [ △Ct = 3.78 （ 1.28 - 6. 09 ） ] and inactive RA [ △Ct = 5.88 （ 3.23 - 8. 94 ）, H = 11. 760, P 〈 0.01 ） ]. The RA group serum GPI levels [ 3.02 （ 2. 02 - 8.39 ） mg/L ] were higher than those of other rheumatic diseases [ 0. 20 （0. 11 -0. 32） mg/L] and healthy controls[0. 18（0. 08 -0. 30） mg,/L]. There were significant differences of serum GPI levels between active RA group [4. 84（2. 81 - 10. 38） mg/L] and inactive RA group[2. 12 （ 1.26 -4. 34） mg/L] （ H=9. 830,P 〈0. 01）. The sensitivities of GPI, anti-MCV and anti-CCP were 68% （ 41/60 ）, 57 % （ 34/60 ）, 58 % （ 35/60 ）, respectively and specificities were 95 % （ 57/60 ）, 92 % （ 55/60 ） and 93% （56/60）, respectively. Conclusions The high expression of GPI mRNA in RA patients shows that it may play a pathological role in the development of RA, and it may be correlated with the activity of RA. It may be a valuable diagnostic parameter for RA, because of its high sensitivity and specificity.