The radioligand assay of protein-tyrosine-phosphatase autoantibody and clinical implications

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CHINESE JOURNAL OF DIABETES
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Volume 12, Issue 01, 2004
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Abstract: ObjectiveTo establish a radioligand assay for protein tyrosine phosphatase autoantibody (IA-2A).Methods 35 S labeling recombinant human IA-2 antigen wa s obtained by in vitro transcription and translation, and then mixed with serum samples in self-made rotating incubator overnight. The IA-2 immunocomplex was precipitated with protein A-agarose, then washed with TBST buffer and counted i n CPM using liquid scintillation counter The results were expressed by IA-2A index. The sensitivity and specificity of the assay were evaluated in the 3rd Di abetes Autoantibody Standardization Program (DASP) 2003 sponsored by the Immuno logy of Diabetes Society (IDS). Also, IA-2A was screened in Chinese diabetic patients (type 1, n=111; type 2, n=113) and healthy controls(n=125 ).ResultsThe intra-assay coefficient of variation (CV ) was 3.2%~9.7%, inter-assay CV 5.6%~11.7%. The IA-2A indices of 45 sa mp les were tested in our laboratory and an international standardized laboratory, which were totally consistent. The IA-2A index cut point was determined accord ing to the upper limit of 99.5 percentile of 125 healthy controls. The index of 0.0065 or higher was defined as positive. The IA-2A positive prevalence was 23 .4 (26/111) in type 1 diabetes and 1.8 (2/113) in type 2 diabetes (χ 2=24.0 ,P<0.001). The IA-2A positive percentage in type 1 diabetic patients was higher in the course of less than 1 year than over 1 year (33.3% vs 15.0%, P <0.05).ConclusionThe established IA-2A radioligand assay h as a high sensitivity, specificity and reproductivity, and it could be used wid ely in clinical practice.

  • [1]Kupila A, Keskinen P, Simell T, et al. Genetic risk determines the emergence of diabetes-associated autoantibodies in young children. Diabetes,2002,51:646-651.
  • [2]Ellis TM, Schatz DA, Ottendorfer EW, et al. The relationship between humoral and cellular immunity to IA-2 in IDDM. Diabetes,1998,47:566-569.
  • [3]沙悦, 王姮, 孙琦, 等. 胰岛自身抗体联合检测在不同病程Ⅰ型糖尿病中的阳性率. 中国医学科学院学报, 2001, 23:273-276.
  • [4]Gianani R, Rabin DU, Verge CF, et al. ICA512 autoantibody radioassay. Diabetes, 1995,44:1340-1344.
  • [5]Woo W, LaGasse JM, Zhou Z, et al. A novel high-throughput method for accurate, rapid, and economical measurement of multiple type 1 diabetes autoantibodies. J Immunol Methods,2000,244:91-103.
  • [6]王建民,周智广,文建新, 等. 谷氨酸脱羧酶(GAD65)自身抗体的放射配体检测法. 中国糖尿病杂志,1997,5:85-88.
  • [7]黄干, 周智广, 彭健, 等.35S标记重组人GAD65抗原检测糖尿病患者GAD-Ab指数.中华核医学杂志, 2003,23:82-86.
  • [8]Bonifacio E, Lampasona V, Genovese S, et al. Identification of protein tyrosine phosphatase-like IA-2 (islet cell antigen 512) as the insulin-dependent diabetes-related 37/40K autoantigen and a target of islet cell antibodies. J Immunol, 1995,155:5419-5426.
  • [9]宗阳,罗敏,丁伟,等. IA-2基因的克隆及原核表达研究. 中华内分泌代谢杂志,2001,17:21-23.
  • [10]Falorni A, Kassi G, Murdolo G, et al. Controversies on humoral immune markers of insulin dependent diabetes mellitus. J Pediatric Endocrinol Metab,1998,11:307-317.
  • [11]周智广, 伍汉文. 成人隐匿性自身免疫性糖尿病的诊断与治疗. 中华内分泌代谢杂志,1998,14:1-2.
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