Sato K, Shimizu T, Akaki T, Tomioka H
Department of Microbiology and Immunology, Shimane Medical University, Japan.
Kekkaku. 1998 Feb;73(2):47-52.
The MycoDot is a new diagnostic kit for tuberculosis which was devised by DynaGen Inc., USA. The MycoDot test is based on the detection of anti-mycobacterial antibodies in the serum samples of patients by employing plastic combs coated with lipoarabinomannan (LAM) antigen which is a highly immunogenic lipopolysaccharide presenting in the cell wall of all species of mycobacteria. It has been reported that healthy infected and BCG-vaccinated individuals do not react to the MycoDot test, while a positive reaction occurs in patients with active tuberculosis or atypical mycobacteriosis with good sensitivity and specificity. In this study, we evaluated the efficacy of MycoDot test for the detection of anti-LAM antibodies in sera of mice infected with Mycobacterium tuberculosis or M. avium complex (MAC). By using the MycoDot test, anti-LAM antibodies were positive in 2 out of 4 mice infected with M. tuberculosis 2 weeks before, while all of M. intracellulare-infected mice were negative at the same phase of infection. On the other hand, anti-mycobacterial (MB) antibodies were detected in the serum samples of mice infected with M. intracellulare as well as M. tuberculosis by home-made ELISA testing using whole cells of test mycobacteria as antigen. In the next experiment, mice were infected with M. avium. All the serum samples of mice obtained at 13 weeks after infection were negative for anti-LAM antibodies in MycoDot test, whereas they reacted positively to anti-MB antibodies in ELISA test. These results indicate that the MycoDot test is capable of detecting M. tuberculosis infection but not MAC infection induced in mice.
MycoDot是美国DynaGen公司设计的一种新型结核病诊断试剂盒。MycoDot检测基于通过使用涂有脂阿拉伯甘露聚糖（LAM）抗原的塑料梳子来检测患者血清样本中的抗分枝杆菌抗体，LAM抗原是一种存在于所有分枝杆菌细胞壁中的高度免疫原性脂多糖。据报道，健康的感染者和接种卡介苗的个体对MycoDot检测无反应，而活动性结核病或非典型分枝杆菌病患者会出现阳性反应，且具有良好的敏感性和特异性。在本研究中，我们评估了MycoDot检测在检测感染结核分枝杆菌或鸟分枝杆菌复合群（MAC）的小鼠血清中抗LAM抗体的功效。通过使用MycoDot检测，4只两周前感染结核分枝杆菌的小鼠中有2只的抗LAM抗体呈阳性，而在相同感染阶段，所有细胞内分枝杆菌感染的小鼠均为阴性。另一方面，通过使用受试分枝杆菌全细胞作为抗原的自制ELISA检测，在细胞内分枝杆菌和结核分枝杆菌感染的小鼠血清样本中检测到了抗分枝杆菌（MB）抗体。在接下来的实验中，小鼠感染了鸟分枝杆菌。感染后13周获得的所有小鼠血清样本在MycoDot检测中抗LAM抗体均为阴性，而在ELISA检测中它们对抗MB抗体呈阳性反应。这些结果表明，MycoDot检测能够检测小鼠中的结核分枝杆菌感染，但不能检测MAC感染。
