用重组 rK39抗原试纸条快速诊断内脏利什曼病

目的 ]评价以恰氏利氏曼原虫类 kinesin基因中编码 39个氨基酸的基因片段 (r K39)为重组抗原 ,用于血清学诊断内脏利什曼病的价值。 方法 ]在新疆喀什地区对 13例经脾检和骨髓穿刺阳性的内脏利什曼病患者 ,取一滴病人全血或血清滴在 r K39抗原试纸条底部的吸收垫上 ,血清中蛋白随缓冲液向试纸条上部移动 ,其中相应特异抗体可与 r K39抗原带结合 ,而产生阳性条带。同时 ,本文亦用相同阳性血清作了关于 r K 39抗原的 Western印迹分析对照。 结果 ]EL ISA分析显示病人血清抗体滴度在 10 - 2～ 10 - 4 ,与所见到的 r K39试纸条上的反应强度符合。Western印迹分析亦显示阳性血清可识别 r K39蛋白条带。结论 ]与传统诊断内脏利什曼病方法相比较 ,r K39试纸条更快速 ,特异 ,灵敏和低损伤性 ,可用于低发病率流行区的内脏利什曼病的诊断和筛选

RAPID SCREENING WITH A RECOMBINANT ANTIGEN (rK39) FOR DIAGNOSIS OF VISCERAL LEISHMANIASIS USING DIPSTICK *

Objective] To evaluate the diagnostic value of the recombinant antigen of 39 amino acid repeats encoded by a kinesin like gene of Leishmania changasi (rK39) in serodiagnosis of visceral leishmaniasis (VL). Methods] In Kashi, Xinjiang, 13 VL patients with splenomegaly and bone marrow aspirate culture positive were subjected to dipstick assay. A drop of whole blood or serum from patient was placed at the absorbing pad at the bottom of the dipstick. Flooding of the bottom protein with buffer allows serum proteins to migrate upwards, producing the positive band and Western blot analysis of rK39 subsequently performed with the sera collected. Results] The end point titers of anti rK39 antibodies of these sera were determined by ELISA and found to fall within the range of 10 -2 to 10 -4 , which were consistent with the intensity of their reaction with rK39 in dipstick assay. The positive sera could also recognize the specific rK39 band as analyzed by Western blot analysis. Conclusion] The rK39 dipstick assay is more rapid, specific, sensitive and less invasive than the conventional methods of diagnosis for VL in the areas of low endemicity.