Jenkins A O, Michel A, Rutten V
Division of Immunology, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
Vet Microbiol. 2017 May;203:286-293. doi: 10.1016/j.vetmic.2017.03.028. Epub 2017 Mar 27.
The role of antigens shared between Mycobacteria in in-vivo cross-reactive immune responses in host animals, have been reported to be responsible for reduced BCG vaccination efficacy as well reduced specificity of routine immunological diagnostic tests. This presents with significant disease control challenges in humans and animals. The present review highlights the results of previous studies on the effect of pre-sensitization to environmental mycobacteria on either pathogenic mycobacteria and/or M. bovis BCG, in experimental animals. It also takes an in-depth view into assessing the genetic similarities and relationships between atypical mycobacteria and Mycobacterium tuberculosis complex (MTBC) and how they might explain the immunological imprint of environmental mycobacteria in directing the hosts' immune response upon subsequent exposure to other classes of mycobacteria. The outcome of this review suggests that genetic closeness between particular atypical mycobacteria and MTBC usually indicate a higher level of homology for certain shared protective antigens. This ultimately results in a higher level of cross reactive immune responses as compared with other atypical mycobacteria that are further away genetically. This would explain the different effects of environmental mycobacteria on MTBC that have been reported in the different studies. In other words the direction of the host immune system in response to exposure to MTBC would depend on the type of environmental mycobacteria that was encountered in the initial exposure. We also explain these mycobacterial interactions in the context of the phenomenon of "Original Mycobacterial Sin". The effects of these inevitable mycobacterial interactions on field diagnosis and control by vaccination and how to circumvent them are discussed.
分枝杆菌之间共享的抗原在宿主动物体内交叉反应性免疫应答中的作用，据报道是卡介苗接种效果降低以及常规免疫诊断测试特异性降低的原因。这给人类和动物的疾病控制带来了重大挑战。本综述重点介绍了先前关于实验动物中对环境分枝杆菌的预致敏对致病性分枝杆菌和/或牛分枝杆菌卡介苗影响的研究结果。它还深入评估了非典型分枝杆菌与结核分枝杆菌复合群（MTBC）之间的遗传相似性和关系，以及它们如何解释环境分枝杆菌在宿主随后接触其他类分枝杆菌时指导宿主免疫反应的免疫印记。本综述的结果表明，特定非典型分枝杆菌与MTBC之间的遗传接近通常表明某些共享保护性抗原具有更高水平的同源性。与其他遗传距离较远的非典型分枝杆菌相比，这最终导致更高水平的交叉反应性免疫应答。这可以解释不同研究中报道的环境分枝杆菌对MTBC的不同影响。换句话说，宿主免疫系统对接触MTBC的反应方向将取决于初次接触时遇到的环境分枝杆菌类型。我们还在“原始分枝杆菌罪”现象的背景下解释了这些分枝杆菌的相互作用。讨论了这些不可避免的分枝杆菌相互作用对现场诊断以及疫苗接种控制的影响，以及如何规避这些影响。
