蛋白酪氨酸磷酸酶2自身抗体微量平板放射结合检测法的建立与临床应用

目的建立蛋白酪氨酸磷酸酶2自身抗体（IA-2A）的微量平板放射结合检测法（RBA），并初步评价其临床应用价值。方法经纯化的^35S-IA-2抗原与血清在96孔V形底平板中缓慢振荡孵育24h，而后转入已包被蛋白A的Millipore平板中，洗涤后采用多功能液体闪烁发光仪计数。检测162例1型糖尿病（T1DM）患者、210例新诊2型糖尿病（T2DM）患者和224名健康者血清中IA-2A浓度，初步评价其临床应用效果。结果（1）该法检测IA-2A批内CV4．1％～10．0％，批间CV5．7％～12．8％。（2）国际第4次糖尿病自身抗体检测标准化评估回报结果显示，其灵敏度为72％，特异度为98％。与放射配体法（RLA）结果判定一致率为96．5％，检测值呈显著正相关（r=0．962，P〈0．01）。（3）IA-2A在T1DM患者中阳性率为22．8％，明显高于健康者的0．89％（P〈0．01）；在T2DM患者中阳性率为2．4％，与健康者相比差异无统计学意义。（4）该法检测指血IA-2A与RLA法检测静脉血结果判定一致率为100％。结论微量平板RBA法灵敏度、特异度、重复性好，能适用于末梢血IA-2A检测，具有较好的临床应用价值。

Establishment of microtiter plate radiobinding assay of autoantibodies to protein tyrosine phosphatase(IA-2A) and its clinical application

Objective To establish the microtiter plate radiobinding assay （RBA） of IA-2A and to evaluate its clinical application. Methods The purified 3sS - IA-2 was incubated with sera for 24 hours on a 96-well V-shaped bottom plate, and then transferred to the Millipore plate coated with protein A, and counted with liquid scintillation and luminescence counters after washing. The IA-2A levels were detected in 162 patients with type 1 diabetes（T1DM）,210 patients with newly diagnosed type 2 diabetes（T2DM） and 224 healthy controls to evaluate clinical application of IA-2A RBA. Results 1. The intra-coefficient of variation （CV） of the assay was 4.1%-10. 0%, and the inter CVwas 5.7%-12.8%. 2. The results from DASP 2005 showed that the sensitivity and specificity of the assay were 72% and 98%. The results of IA-2A from two methods of RBA and classical radioligand assay（RLA） were significantly correlated （r =0. 962,P〈0. 001） with a consistency of 96.5%. 3. When compared with the healthy controls, T1DM patients had higher positivity for IA-2A （22.8% vs 0. 89%, χ^2 = 49.9, P〈0. 001）, but no significant difference was found in T2DM patients（2.4% vs 0. 89%, χ^2 =1.5,P〉0.05）. 4. The consistency rate of IA-2A measurement was 100% between RBA using finger tip blood and RLA using venous blood （r=0. 977,P〈0. 001）. Conclusions The microtiter plate RBA of IA-2A using {inger tip blood has high sensitivity, specificity and reproducibility, and possesses a good clinical value.