The DosR antigen Rv1737c from Mycobacterium tuberculosis confers inflammation regulation in tuberculosis infection

There is an urgent need to identify the potential risk factors for activating latent Mycobacterium tuberculosis infection. In this study, we evaluated the immune function of Rv1737c, which is a latency‐associated antigen of dormancy survival regulator (DosR) of M. tuberculosis in a mouse model. Our data showed that mice pretreated with recombinant Rv1737c (rRv1737c) exhibited higher levels of antigen‐specific antibodies (IgG, IgM and IgA) than sham‐treated mice. Following Bacilli Calmette‐Guerin (BCG) challenge, rRv1737c adjuvanted with cholera toxin subunit B (CTB) induced diffuse lung inflammation and fibrosis compared to the control mice. The inflammatory pathogenesis due to rRv1737c pre‐exposure was associated with a switch in the macrophage phenotype from M1 to activated M2 and was characterized by IL‐10 production. Intracellular cytokine analysis further showed that the rRv1737c‐pretreated mice exhibited an increased frequency of Th2 cells in the lungs, lymph nodes and spleen after BCG challenge. Furthermore, IFN‐γ expression increased in the lungs after rRv1737c pretreatment compared to that in the sham mice. Accordingly, lung cells from rRv1737c‐immunized mice stimulated with killed BCG produced higher levels of multiple cytokines, such as IFN‐γ, IL‐10 and IL‐6. The results confirmed that the pathological features of rRv1737c promoted inflammation. Overall, our findings provide direct evidence of the pro‐inflammatory function of rRv1737c in a murine model of BCG infection, indicating that Rv1737c is a pathogenic antigen of M. tuberculosis and may be key to the recurrence of latent infection.     

白细胞介素32与结核病的研究进展

白细胞介素32(interleukin 32,IL-32)是一种潜在性非常高的促炎症细胞因子(cytokine,CK),在很多炎症性疾病中都能检测到它的存在。相关疾病的研究中,其在传染性结核病(tuberculosis,TB)领域的研究于最近几年有一定的进展,有研究表明IL-32与结核病的免疫机制相关。这对于结核病致病机理研究、有效诊断和治疗可能有重要意义。     

Mycobacterium abscessus Complex – a Particular Challenge in the Setting of Lung Transplantation

Mycobacterium abscessus complex is an emerging pathogen in lung transplant candidates and recipients. M. abscessus complex is widespread in the environment and can cause pulmonary, skin and soft tissue, and disseminated infection, particularly in lung transplant recipients. It is innately resistant to many antibiotics making it difficult to treat. Herein we describe the epidemiology, clinical manifestations, diagnosis and treatment of M. abscessus with an emphasis on lung transplant candidates and recipients. We also outline the areas where data are lacking and the areas where further research is urgently needed.     

耐多药结核病诊断方法研究进展

耐多药结核病的防治对于结核病的防控具有重要意义,已成为结核病防治的难点和热点问题。早期对结核病患者进行耐多药检测能够提高耐多药结核病患者的治疗成功率。耐多药结核病的诊断方法包括传统的培养方法及新型分子生物学诊断方法。作者对耐多药结核病的诊断方法进行综述,以期为耐多药结核病防治提供科学依据。     

Mycobacterium Species Related to M. leprae and M. lepromatosis from Cows with Bovine Nodular Thelitis

Bovine nodular thelitis is a granulomatous dermatitis associated with infection with acid-fast bacteria. To identify the mycobacterium responsible for this infection, we conducted phylogenetic investigations based on partial sequencing of 6 genes. These bacteria were identified as an undescribed Mycobacterium species that was phylogenetically related to M. leprae and M. lepromatosis.     

Distinct Strategies Employed by Dendritic Cells and Macrophages in Restricting Mycobacterium tuberculosis Infection: Different Philosophies but Same Desire

Dendritic cells (DCs) and macrophages (M?s) are professional antigen-presenting cells (APCs) that can efficiently phagocytose Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB). It is quite interesting to mention here that DCs and M?s use distinct strategies to combat and eliminate Mtb. Similarly, Mtb employs different mechanisms to counteract the action of DCs and M?s. M?s are evolved with specialized, innate, defensive machinery to restrict growth of Mtb at the initial phase of infection. However, DCs are more endowed toward initiating adaptive immunity by activating naïve T cells. During encounter with Mtb, DCs and M?s deliver discrete functions via triggering through different pattern recognition receptors (PRRs) expressed by these APCs. Mtb-infected DCs and M?s show differential expression of genes encoding cytokines, chemokines, costimulatory molecules, and adhesion molecules. Interestingly, Mtb impairs the immune defensive machinery by exploiting various PRRs. Remarkably, selective signaling through PRRs by Mtb abrogates the bactericidal activity of M?s, but subverts differentiation of monocytes to DCs. In this article, we highlight the role of PRRs in inducing distinct immune response by DCs and M?s against Mtb. Concurrently, we also discuss smart strategies exploited by Mtb to impair the function of host DCs and M?s.     

Epidemiology of Primary Multidrug-Resistant Tuberculosis,Vladimir Region,Russia

We studied the epidemiology of drug-resistant tuberculosis (TB) in Vladimir Region, Russia, in 2012. Most cases of multidrug-resistant TB (MDR TB) were caused by transmission of drug-resistant strains, and >33% were in patients referred for testing after mass radiographic screening. Early diagnosis of drug resistance is essential for preventing transmission of MDR TB.