共 31 条
Enhanced contact tracing and spatial tracking of Mycobacterium tuberculosis infection by enumeration of antigen-specific T cells
被引:334
作者:
Lalvani, A
[1
]
Pathan, AA
Durkan, H
Wilkinson, KA
Whelan, A
Deeks, JJ
Reece, WHH
Latif, M
Pasvol, G
Hill, AVS
机构:
[1] Univ Oxford, John Radcliffe Hosp, Nuffield Dept Clin Med, Oxford OX3 9DU, England
[2] Northwick Pk Hosp & Clin Res Ctr, Imperial Coll Sch Med, Wellcome Ctr Clin Trop Med, Harrow HA1 3UJ, Middx, England
[3] Northwick Pk Hosp & Clin Res Ctr, TB Contact Tracing Clin, Harrow HA1 3UJ, Middx, England
[4] Vet Labs Agcy, Dept Bacterial Dis, TB Res Grp, Weybridge, Surrey, England
[5] Inst Hlth Sci, Ctr Stat Med, Oxford, England
来源:
基金:
英国惠康基金;
关键词:
D O I:
10.1016/S0140-6736(00)05115-1
中图分类号:
R5 [内科学];
学科分类号:
1002 ;
100201 ;
摘要:
Background Identification of individuals latently infected with Mycobacterium tuberculosis is an important part of tuberculosis control. The current method, the tuberculin shin test (TST), has poor specificity because of the antigenic cross-reactivity of purified protein derivative (PPD) with M bovis BCG vaccine and environmental mycobacteria. ESAT-6 is a secreted antigen that is highly specific for M tuberculosis complex, but is absent from M bovis BCG. With an enzyme-linked immunospot (ELISPOT) assay for interferon gamma, we have identified ESAT-6-specific T cells as an accurate marker of M tuberculosis infection. Methods We did a prospective, masked study of 50 healthy contacts, with varying but well defined degrees of exposure to M tuberculosis, who attended an urban contact-tracing clinic. We assessed and compared the efficacy of our assay and TST for detection of symptomless infected individuals by correlation of test results with the degree of exposure to an infectious index case. Findings The ESAT-6 ELISPOT assay results had a strong positive relation with increasing intensity of exposure (odds ratio=9.0 per unit increase in level of exposure [95% CI 2.6-31.6], p=0.001), whereas TST results had a weaker relation with exposure (1.9 [1.0-3.5], p=0.05). By contrast, ELISPOT results were not correlated with BCG vaccination status (p=0.7), whereas TST results were significantly more likely to be positive in BCG-vaccinated contacts (12.1 [1.3-115.7], p=0.03). Interpretation This new antigen-specific T cell-based assay could allow more accurate identification of symptom-free individuals recently exposed to M tuberculosis, and thereby help to improve tuberculosis control.
引用
收藏
页码:2017 / 2021
页数:5
相关论文