Usefulness of the IgA and IgG Responses to Macrophage Migration Inhibitory Factor for the Diagnosis of Tuberculosis.

Serological tests offer the potential in order to improve the diagnosis of tuberculosis (TB). Macrophage migration inhibitory factor (MIF) plays a protective role in infection control in TB; however, to date, no studies on antibody responses to MIF have been reported. We measured immunoglobulin (Ig)A and IgG responses to MIF in individuals with either active tuberculosis (ATB; = 65), latent tuberculosis (LTBI; = 53), or in non-infected individuals (NI; = 62).

Diagnostic Potential of IgG and IgA Responses to t Antigens for Discrimination among Active Tuberculosis, Latent Tuberculosis Infection, and Non-Infected Individuals.

Tuberculosis remains a major public health problem. Conventional tests are inadequate to distinguish between active tuberculosis (ATB) and latent tuberculosis infection (LTBI). We measured antibody responses to antigens ( chorismate mutase (TBCM), antigen 85B (Ag85B), early secreted antigen-6 (ESAT-6), and culture filtrate protein-10 (CFP-10) in ATB, LTBI, and non-infected (NI) individuals.

Mycobacterium abscessus infection leads to enhanced production of type 1 interferon and NLRP3 inflammasome activation in murine macrophages via mitochondrial oxidative stress.

Mycobacterium abscessus (MAB) is a rapidly growing mycobacterium (RGM), and infections with this pathogen have been increasing worldwide. Recently, we reported that rough type (MAB-R) but not smooth type (MAB-S) strains enhanced type 1 interferon (IFN-I) secretion via bacterial phagosome escape, contributing to increased virulence. Here, we sought to investigate the role of mitochondrial oxidative stress in bacterial survival, IFN-I secretion and NLRP3 inflammasome activation in MAB-infected murine macrophages.

Heat-killed Mycobacterium paragordonae therapy exerts an anti-cancer immune response via enhanced immune cell mediated oncolytic activity in xenograft mice model.

A therapeutic strategy capable of skewing toward a Th1-type immune response is crucial for cancer treatment. Recently, we reported Mycobacterium paragordonae (Mpg) as a potential live vaccine for mycobacterium infections. In this study, we explored the immunotherapeutic potential of heat-killed Mpg (HK-Mpg) in a mouse tumor xenograft model and elucidated its underlying antitumor mechanisms.

Potential of recombinant Mycobacterium paragordonae expressing HIV-1 Gag as a prime vaccine for HIV-1 infection.

Recombinant Mycobacterium strains such as recombinant BCG (rBCG) have received considerable attention for the HIV-1 vaccine development. Recently, we described a temperature-sensitive Mycobacterium paragordonae (Mpg) strain as a novel live tuberculosis vaccine that is safer and showed an enhanced protective effect against mycobacterial infection compared to BCG. We studied the possibility of developing a vaccine against HIV-1 infection using rMpg strain expressing the p24 antigen (rMpg-p24).

rt269I Type of Hepatitis B Virus (HBV) Leads to HBV e Antigen Negative Infections and Liver Disease Progression via Mitochondrial Stress Mediated Type I Interferon Production in Chronic Patients With Genotype C Infections.

Hepatitis B virus infection is a serious global health problem and causes life-threatening liver disease. In particular, genotype C shows high prevalence and severe liver disease compared with other genotypes. However, the underlying mechanisms regarding virological traits still remain unclear.

Insights From the Genome Sequence of , a Potential Novel Live Vaccine for Preventing Mycobacterial Infections: The Putative Role of Type VII Secretion Systems for an Intracellular Lifestyle Within Free-Living Environmental Predators.

(Mpg) is a temperature-sensitive species that can grow at permissive temperatures but fails to grow above 37°C. Due to this unique growth trait, Mpg has recently been proposed as a novel live vaccine candidate for the prevention of mycobacterial infections. Furthermore, the increasing frequency of the isolation of Mpg from water supply systems led us to hypothesize that the free-living amoeba system is the natural reservoir of Mpg.

Phagosome Escape of Rough Strains in Murine Macrophage via Phagosomal Rupture Can Lead to Type I Interferon Production and Their Cell-To-Cell Spread.

complex (MAB) is a rapidly growing mycobacterium(RGM) whose clinical significance as an emerging human pathogen has been increasing worldwide. It has two types of colony morphology, a smooth (S) type, producing high glycopeptidolipid (GPL) content, and a rough (R) type, which produces low levels of GPLs and is associated with increased virulence. However, the mechanism responsible for their difference in virulence is poorly known.

A description of Mycobacterium chelonae subsp. gwanakae subsp. nov., a rapidly growing mycobacterium with a smooth colony phenotype due to glycopeptidolipids.

Three rapidly growing mycobacterial strains, MOTTH4W, MOTT36W and MOTT68W, were isolated from the sputa of three independent Korean patients co-infected with Mycobacterium yongonense Type II strains. The 16S rRNA gene sequences of all three strains were unique, which were closest to that of Mycobacterium chelonae subsp. bovis KCTC 39630 (99.

Development of a Live Recombinant BCG Expressing Human Immunodeficiency Virus Type 1 (HIV-1) Gag Using a pMyong2 Vector System: Potential Use As a Novel HIV-1 Vaccine.

Even though the rate of new human immunodeficiency virus type 1 (HIV-1) infections is gradually decreasing worldwide, an effective preventive vaccine for HIV-1 is still urgently needed. The recombinant BCG (rBCG) is promising for the development of an HIV-1 vaccine. Recently, we showed that a recombinant expressing HIV-1 gag in a pMyong2 vector system (rSmeg-pMyong2-p24) increased the efficacy of a vaccine against HIV-1 in mice.

Patterns of rpoC Mutations in Drug-Resistant Mycobacterium tuberculosis Isolated from Patients in South Korea.

Background: Rifampicin (RFP) is one of the principal first-line drugs used in combination chemotherapies against Mycobacterium tuberculosis, and its use has greatly shortened the duration of chemotherapy for the successful treatment of drug-susceptible tuberculosis. Compensatory mutations have been identified in rpoC that restore the fitness of RFP-resistant M. tuberculosis strains with mutations in rpoB.

Role of the DNA Mismatch Repair Gene in Driving the Evolution of Type I via Homologous Recombination.

We recently showed that could be divided into two genotypes: Type I, in which the gene has been transferred from , and Type II, in which the gene has not been transferred. Comparative genome analysis of three Type I, two Type II and type strains were performed in this study to gain insight into gene transfer from into Type I strains. We found two genome regions transferred from : one contained 3 consecutive genes, including the operon, and the other contained 57 consecutive genes that had been transferred into Type I genomes via homologous recombination.

A temperature sensitive Mycobacterium paragordonae induces enhanced protective immune responses against mycobacterial infections in the mouse model.

Recently, we introduced a temperature sensitive Mycobacterium spp., Mycobacterium paragordonae (Mpg). Here, we checked its potential as a candidate for live vaccination against Mycobacterium tuberculosis and Mycobacterium abscessus.

Description of Mycobacterium chelonae subsp. bovis subsp. nov., isolated from cattle (Bos taurus coreanae), emended description of Mycobacterium chelonae and creation of Mycobacterium chelonae subsp. chelonae subsp. nov.

Three rapidly growing mycobacterial strains, QIA-37, QIA-40 and QIA-41, were isolated from the lymph nodes of three separate Korean native cattle, Hanwoo (Bos taurus coreanae). These strains were previously shown to be phylogenetically distinct but closely related to Mycobacterium chelonae ATCC 35752 by taxonomic approaches targeting three genes (16S rRNA, hsp6 and rpoB) and were further characterized using a polyphasic approach in this study. The 16S rRNA gene sequences of all three strains showed 99.

Effect of amikacin on cell wall glycopeptidolipid synthesis in Mycobacterium abscessus.

Cultivation of the smooth colony Mycobacterium abscessus at the sub-minimum inhibitory concentration (MIC) of amikacin changed its growth pattern including its colony morphology (smooth to rough) and cell arrangement (dispersed to cord formation). In addition, reduced sliding motility and biofilm formation were observed. The amount of glycogpetidolipid (GPL) and mRNA expression of key genes involved in GPL synthesis were decreased in the amikacin-treated M.

Phylogenetic analysis of Mycobacterium massiliense strains having recombinant rpoB gene laterally transferred from Mycobacterium abscessus.

Recent multi locus sequence typing (MLST) and genome based studies indicate that lateral gene transfer (LGT) events in the rpoB gene are prevalent between Mycobacterium abscessus complex strains. To check the prevalence of the M. massiliense strains subject to rpoB LGT (Rec-mas), we applied rpoB typing (711 bp) to 106 Korean strains of M.

Identification of Novel A2/C2 Inter-Genotype Recombinants of Hepatitis B Virus from a Korean Chronic Patient Co-Infected with Both Genotype A2 and C2.

Nearly all cases of Hepatitis B virus (HBV) infections in South Korea have the C2 genotype. Here, we have identified a chronically infected patient who was co-infected with HBV of both the A2 and C2 genotypes by screening 135 Korean chronically infected patients using direct sequencing protocols targeting the 1032-bp polymerase reverse transcriptase (RT) region. Further polymerase chain reaction (PCR)-cloning analysis (22 clones) of the RT showed that this patient had genotype C2 (12 clones), genotype A2 (six clones) and A2/C2 inter-genotype HBV recombinants (four clones).

Recombinant Mycobacterium smegmatis with a pMyong2 vector expressing Human Immunodeficiency Virus Type I Gag can induce enhanced virus-specific immune responses.

Recently, we have developed a novel Mycobacterium-Escherichia coli shuttle vector system using pMyong2, which can provide an enhanced expression of heterologous genes in recombinant Mycobacterium smegmatis (rSmeg). To investigate the usefulness of rSmeg using pMyong2 in vaccine application, we vaccinated M. smegmatis with pMyong2 system expressing Human Immunodeficiency Virus Type I (HIV-1) Gag p24 antigen (rSmeg-pMyong2-p24) into mice and examined its cellular and humoral immune responses against HIV gag protein.

Mycobacterium paraintracellulare sp. nov., for the genotype INT-1 of Mycobacterium intracellulare.

Three mycobacterial strains, isolated from independent Korean patients with pulmonary infections, belonging to the Mycobacterium intracellulare genotype 1 (INT-1) were characterized using a polyphasic approach. The sequences of the 16S rRNA gene and internal transcribed spacer 1 (ITS1) of the INT-1 strains were identical to those of Mycobacterium intracellulare ATCC 13950T. However, multilocus sequence typing (MLST) analysis targeting five housekeeping genes (hsp65, rpoB, argG, gnd and pgm) revealed the phylogenetic separation of these strains from M.

Molecular Taxonomic Evidence for Two Distinct Genotypes of Mycobacterium yongonense via Genome-Based Phylogenetic Analysis.

Recently, we introduced a distinct Mycobacterium intracellulare INT-5 genotype, distantly related to other genotypes of M. intracellulare (INT-1 to -4). The aim of this study is to determine the exact taxonomic status of the M.

A telomerase-derived peptide regulates reactive oxygen species and hepatitis C virus RNA replication in HCV-infected cells via heat shock protein 90.

GV1001, a synthetic peptide derived from human telomerase, has a range of diverse biological activities, including an antioxidant function. Here, we investigated the role of GV1001 in hepatitis C virus (HCV)-infected Huh7.5 (JFH-1) cells.

Identification of ISMyo2, a novel insertion sequence element of IS21 family and its diagnostic potential for detection of Mycobacterium yongonense.

Background: Mycobacterium yongonense, as a novel member of the M. avium complex (MAC), was recently reported to be isolated from human specimens in South Korea and Italy. Due to its close relatedness to other MAC members, particularly M.

Mycobacterium massiliense Type II genotype leads to higher level of colony forming units and TNF-α secretion from human monocytes than Type I genotype.

Recently, we introduced a novel Mycobacterium massiliense Type II genotype from Korean patients, in which all isolates showed only a rough (R) colony morphotype. In this study, we sought to compare clinical factors and virulence potentials of two genotypes of M. massiliense, Type I and Type II.

Separation of Mycobacterium abscessus into subspecies or genotype level by direct application of peptide nucleic acid multi-probe- real-time PCR method into sputa samples.

Background: Recently, we introduced a novel peptide nucleic acid (PNA) multi-probe real time PCR method targeting the hsp65 gene (hsp65 PNA RT-PCR) to distinguish Mycobacterium abscessus groups.

Methods: Here, we evaluated the usefulness of the hsp65 PNA RT-PCR for the direct identification of the M. abscessus group at the subspecies and genotype levels from sputa samples.