Preliminary observation of targeted contrast agent of CT in the acute tuberculosis animal model / 中华放射学杂志

ABSTRACT

Objective To explore the feasibility of anti-85B and ESAT-6 monoclonal antibodies targeted contrast agent of CT by the murine acute tuberculosis animal model.Methods Preparation the targeted contrast agent of computed tomography by iodine atoms coupled with anti-85B and ESAT-6 murine monoclonal antibodies after purified.Calculate the label rate and the quality of 127Ⅰ of the targeted contrast agent solution,and dilute the contrast agent solution to the required concentration (5μg I/ml) to spare.There were twenty mice of acute tuberculosis animal model,which were divided into four groups by completely randomized digital table and each group was five animals.According to the different antibody named as 85B group and ESAT-6 group of targeted contrast agent,common contrast agent and blank control separately.The common contrast agent group was injected with diluents of iohexol,which was diluted into the same concentration with the targeted contrast agent.The control group was injected with antibody diluents pH 7.4 Phosphate Buffered Saline (PBS).All the animals were scanned before and after injection the contrast agent in different time,such as immediate,6 hours,12 hours and 24 hours.Observe the display and changes of the murine tuberculosis lesions,and measurement the CT value,which was regarded as evaluating mark.Enhancement ratio was also calculated.Two sample mean differences with t test and the multiple sample mean differences with ANOVA.Results The volume of anti-85B contrast agent solution was 2.52 ml,and the quality of antibody and 127Ⅰ were range from 210 to 255 μg and 10.5 to 16.6 μg respectively.The volume of anti-ESAT-6 contrast agent solution was 2.93 ml,and the quality of antibody and 127Ⅰ were 147 μg and 20.58 μg respectively.The lesions of the control group showed no visible density changes before and after injection of PBS.The CT value of the lung lesions in the targeted contrast agent group were gradually increased with time,and the lesion showed visible enhancement after the contrast injection twelve hours(t12),and also remained visible enhancement after injection twenty-four hours(t24)[85B group t12 =(-125.04 ± 13.58) HU,t24 =(-117.37 ± 12.28) HU and ESAT-6 group t12 =(-122.14 ± 19.01) HU,t24 =(-114.23 ± 17.08) HU],which is significant difference compared to the common contrast agent [t (85B-24 h) =4.05,t (ESAT-6-24 h) =6.39,P ＜ 0.05].Conclusions The targeted property of anti-85B and ESAT-6 murine monoclonal antibody contrast agent of CT had been partly proved by the acute tuberculosis animal model.Also provided an experimental basis for further study of tuberculosis targeted contrast agent.