免疫斑点法早期诊断结核性脑膜炎实验研究

The Early Diagnosis on Tuberculous Meningitis by Dot Immunobinding Assay (Dot-Iba)

目的建立免疫斑点法检测结核杆菌抗原,探讨应用免疫斑点法对早期快速诊断结核性脑膜炎的应用价值。方法以D(λ)值(取对数Log)为纵坐标,抗原浓度(取对数Log)为横坐标,绘制标准曲线,求出回归方程。结果确定兔抗结核杆菌PPD多克隆抗体浓度1∶200(20μg/mL)、通用型酶标抗体浓度1∶10为最佳反应浓度组合;回归方程Y=0.9982X-0.9229,P<0.001。最小结核杆菌抗原检出量为3.65ng/mL。结论此法灵敏度高、特异性强,简便、快捷,不需特殊仪器,结果可保存,适合我国国情,适于在广大临床实验室推广应用。

Objective To establish an early diagnostic method for quick test in the tuberculous meningitis. Methods The detection of content of the Mycobacterium tuberculosis antigen with dot immunobinding assay method （Dot-Iba） was established. A standard curve was plotted for deriving the regression equation and correlation coefficient based on the data obtained and the analysis of the variation of D（λ）in relation to the content of antigen. Results The optimal dilution of rabbit anti-Mycobacterium tuberculosis PPD polyclonal antibody and that of the universal conjugate HRP-Anti Ms/Rb IgG are 1 ： 200 （20μg/mL） and 1 ： 10 respectively. Through further dilution of the antigens, a regression equation and the correlation coefficient can be derived （ y = 0. 9982X-0. 9229, P（0. 001 ） . By using this method, the minimum detectable quantities of tubercle bacillus antigen is 3.65ng/mL. Conclusions The sensitivity and specificity of the method is high, and easy to be used without requirement of any special instrument. Furthermore, the original records of Dot-Iba results obtained can be stored. It proves to be a method that is suitable for clinical applications extensively and is well be adapted to our national conditions.