Bartonellosis is spotlighted recently as an emerging zoonosis and Bartonella henselae is reported to be the main infectious agent. In Korea, however, few studies have been made on the epidemiology and microbiology on bartonellosis. Thus, this study was conducted to produce a new monoclonal antibody that can be used for identifying B. henselae. In order to prepare monoclonal antibodies against B. henselae, we inoculated mice with the isolated strain from Korean patient and performed cell fusion experiment. The selected hybridoma clones produced monoclonal antibodies which showed positive immunofluorescence staining of bacteria and specific protein bands in western blot analysis. In order to examine whether these antibodies could be used for the identifying and quantifying Bartonella, we performed confocal microscopy and flow cytometry using the new antibodies. These monoclonal antibodies can be used as a useful tool in further researches on the biology of Bartonella.
Animals ; Antibodies ; Antibodies, Monoclonal ; Bacteria ; Bartonella ; Bartonella henselae ; Bartonella Infections ; Biology ; Blotting, Western ; Cell Fusion ; Clone Cells ; Flow Cytometry ; Fluorescent Antibody Technique ; Humans ; Hybridomas ; Korea ; Mice ; Microscopy, Confocal ; Sprains and Strains

Vibrio vulnificus, a gram-negative halophilic marine bacterium and opportunistic human pathogen, must withstand various environmental changes, especially simultaneous changes in temperature and salinity, from 25degrees C/2.5% to 37degrees C/0.9% (SCTS) upon entering the human body. In our previous study, SCTS stimulated vvpE expression even in the background of a mutation in luxS encoding LuxS enzyme for the biosynthesis of quorum-sensing (QS) signal molecule autoinducer-2 (AI-2), suggesting that the A1-2-mediated QS system is partially involved in the SCTS-mediated change of vvpE expression. In this study, we examined the effects of the QS master regulator SmcR on SCTS-mediated changes in vvpE expression and extracellular VvpE production. SCTS stimulated V. vulnificus growth, but with no increase in maximal growth levels. The SCTS-mediated prolongation of the stationary growth phase resulted in a significant increase in growth phase-dependent smcR and vvpE expressions. A mutation in smcR seriously repressed vvpE expression, but had no significant effect on V. vulnificus growth. However, the smcR mutation only partially attenuates SCTS-mediated changes in vvpE expression. These results indicate that SCTS stimulates the expressions of smcR and vvpE by stimulating V. vulnificus growth, and that SmcR is only partially involved in SCTS-mediated changes in vvpE expression.
Human Body ; Humans ; Salinity ; Vibrio ; Vibrio vulnificus

Mycobacterium abscessus belongs to a group of rapidly growing mycobacteria (RGM) that cause a broad spectrum of infections in humans. In addition, the association of M. abscessus with the cause of community- and hospital-acquired infections has been recently reported. In fact, M. abscessus is known to be the most drug-resistant mycobacterium and naturally resistant to first-line anti-tuberculous drugs, resulting in the limited therapeutic options and a high failure rate of treatment response. Three closely related species; M. abscessus (sensu stricto), M. bolletii, and M. massiliense are currently identified however, consensus on the naming of M. abscessus-related species has not been made to date. We herein discuss the advanced understanding of the virulence potentials and pathophysiological features of M. abscessus to establish novel therapeutic strategies for M. abscessus infection.
Consensus ; Humans ; Mycobacterium

Neisseria gonorrhoeae is the causative agent of gonorrhea, one of the most important sexually transmitted diseases. The incidence of gonorrhea is still prevalent and about 50,000 new cases have been reported annually during the late 2000s in Korea. The antimicrobial resistance of N. gonorrhoeae is very prevalent and most isolates are multi-drug resistant to penicillin G, tetracycline, and fluoroquinolones. The incidence of penicillinase-producing N. gonorrhoeae (PPNG) decreased significantly, but high-level tetracycline-resistant N. gonorrhoeae (TRNG) increased recently. The minimum inhibitory concentrations (MICs) of ceftriaxone were within the susceptible range for all isolates, but MIC creep has been apparent and one cefixime-nonsusceptible isolate (0.5 microg/ml) was found. Spectinomycin-resistant isolates remain rare, but caution should be required when dealing with gonococcal pharyngitis.
Ceftriaxone ; Fluoroquinolones ; Gonorrhea ; Incidence ; Korea ; Microbial Sensitivity Tests ; Neisseria ; Neisseria gonorrhoeae ; Penicillin G ; Pharyngitis ; Sexually Transmitted Diseases ; Tetracycline

Antimicrobial resistance in bacteria is problematic in clinical settings and is a growing threat to public health. Multidrug-resistant and pandrug-resistant non-fermenters such as Acinetobacter spp. and Pseudomonas aeruginosa have recently emerged as a great concern worldwide. Particularly, the prevalence of carbapenem resistance in Acinetobacter spp. and P. aeruginosa is problematic, and emergence of polymyxin resistance is ominous. In this review, we discuss carbapenem and polymyxin resistance in Acinetobacter spp. and P. aeruginosa isolates and their major clones.
Acinetobacter ; Bacteria ; Carbapenems ; Clone Cells ; Polymyxins ; Prevalence ; Pseudomonas ; Pseudomonas aeruginosa ; Public Health

To investigate the occurrence and distribution of serotype, specific virulence genes, and pulse field gel electrophoresis (PFGE) patterns in Vibrio parahaemolyticus isolates from Jeonnam, Korea, we tested 87 strains which were identified with V. parahaemolyticus from diarrheal episode patients in 2005. In this study, 16 different O:K serotype combinations of V. parahaemolyticus were determined. The distributions of O and K serotypes were O4:K68 (51.72%), O1:K70 (18.39%), O3:K6 (5.74%), O1:K68 (4.60%) and O3:K57 (4.60%) respectively. Serotype O4:K68 was the regional dominant specific serotype of V. parahaemolyticus in Sinan of Jeonnam, Korea. For the detection of thermostable direct hemolysin (tdh) and TDH-related hemolysin (trh) gene of V. parahaemolyticus, PCR was performed. The tdh gene was detected in all of the V. parahaemolyticus isolates from diarrheal patients, but trh gene was not detected. Analysis of PFGE patterns of 30 V. parahaemolyticus isolates showed 3 groups and 20 types. Among 14 O4:K68 serotypes which were isolated in Sinan, PFGE patterns of 12 strains were closely related (100%), but 2 strains were related by 58.3% and 45.4%, respectively. Also two strains of O1:K4 serotype in Gurye and two strains of O3:K6 serotype in Yeosu were closely related (100%), respectively. Although serotypes (O1:K4, O1:K70, O3:K6 and O4:K68) were different, PFGE patterns were related for more than 80.9%. Therefore, the epidemiological surveillance of V. parahaemolyticus is required by PFGE typing scheme as a further diagnostic tool.
Bacterial Toxins ; Electrophoresis ; Hemolysin Proteins ; Humans ; Korea ; Polymerase Chain Reaction ; Serotyping ; Vibrio ; Vibrio parahaemolyticus

Immunotherapy with regulatory T lymphocytes is considered to be an attractive new therapeutic modality to prevent allograft rejection. The success of this new therapy is critically dependent on the preparation of highly effective and enough number of regulatory T cells. Here, we tried to establish a proper strategy for the ex vivo expansion of regulatory T cells and evaluated their characteristics. CD4+CD25h+CD62L+ T cells were isolated from the recipient mice and weekly stimulated with various stimuli in the presence of IL-2. The most efficient protocol for the expansion of regulatory T cells maintaining Foxp3 expression and regulatory activity was the three cycles stimulation with donor bone marrow-derived dendritic cells (BM-DCs) which yielded around 400 fold expansion of regulatory T cells. The in vitro-expanded regulatory T cells expressing lymph node homing receptors on their cell surface, were composed of polyclonal population, and did not acquire the ability to produce effector cytokines. Importantly, these expanded regulatory T cells induced a modest prolongation of skin allograft survival when combined with transient T cell depletion in recipient mice. These data indicate that our protocol could be used to obtain an effective population of natural regulatory T cells available for the regulatory T cell therapy to prevent allograft rejection.
Animals ; Cytokines ; Dendritic Cells ; Humans ; Immunotherapy ; Interleukin-2 ; Mice ; Receptors, Lymphocyte Homing ; Rejection (Psychology) ; Skin ; T-Lymphocytes ; T-Lymphocytes, Regulatory ; Tissue Donors ; Tissue Therapy ; Transplantation, Homologous

Endothelin-1 (ET-1) has been characterized as a potent vasoconstrictor secreted by the endothelium, and play a major role in the regulation of vascular tone. It has been also known to participate in inflammatory reactions. The production of ET-1 by macrophages during infection and inflammation is related to tissue perfusion and leukocyte extravasation. The aim of this study is to investigate the role of IL-8/CXCL8, as a major inflammatory chemokine, for ET-1 expression in macrophges. Expression of ET-1 mRNA in mouse peritoneal macrophages (PeM phi) was weaker than that in vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). However, expression of IL-8/CXCL8-induced ET-1 mRNA in PeM phi was much more stronger than that in SHR and WKY VSMCs. Maximum expression of ET-1 mRNA was observed at 50 ng/ml dose of IL-8/CXCL8 and occurred at 2 h after addition of IL-8/CXCL8. Expression of ET-1 by IL-8/CXCL8 was dependent on NF-kappaB activation and ERK1/2 phosphorylation. Baicalein, a 12-lipoxygenase (LO) inhibitor, inhibited the expression of IL-8/CXCL8-induced ET-1 mRNA. This inhibitory action of baicalein was mediated via ERK1/2 inactivation. Induction of 12-LO mRNA by IL-8/CXCL8 and expression of ET-1 mRNA by 12-LO metabolite, 12(S)-HETE were also detected. The expression of IL-8/CXCL8-induced ET-1 mRNA was not detected in PeM phi transfected with 12-LO siRNA. These results suggest that IL-8/CXCL8 can act as one of main inducers of ET-1 in vascular inflammatory reactions, and ET-1 expression by IL-8/CXCL8 is related to 12-LO pathway in PeM phi.
Animals ; Arachidonate 12-Lipoxygenase ; Endothelin-1 ; Endothelium ; Flavanones ; Inflammation ; Leukocytes ; Macrophages ; Macrophages, Peritoneal ; Mice ; Muscle, Smooth, Vascular ; NF-kappa B ; Perfusion ; Phosphorylation ; Rats ; Rats, Inbred SHR ; RNA, Messenger ; RNA, Small Interfering

In Gwangju, Korea, over the last 4 years, human gastrointestinal infection caused by shiga toxin-producing E. coli (STEC) increased. The aim of this study was to ascertain the genetic relatedness of STEC strains by pulsed-field gel electrophoresis (PFGE), as no data on the molecular epidemiology of STEC in Gwangju has yet been published. The PFGE banding patterns were defined for 62 of the 67 STEC strains isolated from cattle and human. There were 11 clonal types in the 11 STEC strains of cattle origin. Among the 11 STEC strains from asymptomatic person, four O91 strains were 100% similarity in band profiles. In the STEC strains isolated from diarrhea patients, same serogroups were grouped to the same cluster; O111 stains were 89.5% similarity, O157 strains 80%, O26 strains 81.5%, and O103 strains 91% similarity, respectively. In conclusion, this is the first report that a large collection of STEC strains from Korea has been analyzed, and a high degree of diversity was observed among the strains analyzed by this technique. PFGE analysis revealed that the strains isolated from human and cattle were closely related within serotypes, and it was useful for epidemiological analysis of STEC. The importance and usefulness of active laboratory surveillance of STEC such as PFGE should be recommended.
Animals ; Cattle ; Coloring Agents ; Diarrhea ; Electrophoresis ; Electrophoresis, Gel, Pulsed-Field ; Humans ; Korea ; Molecular Epidemiology ; Shiga-Toxigenic Escherichia coli

Tuberculosis, which is caused by Mycobacterium tuberculosis (M. tb), is one of the most important infectious diseases in the world. Although many functional studies have been conducted on M. tb proteins in the post-genomic era, little is known about the function of many proteins expressed specifically during latency. Previously, we reported that Rv2041c from M. tb H37Rv is highly expressed under conditions of low pH and hypoxia, which represent the in vitro mimicry of latent tuberculosis. In the present study, increased expression levels of Rv2041c under hypoxia and low pH in vitro culture was confirmed by RT-PCR. Interestingly, Rv2041c showed significantly increased expression among genes of the same operon and genes belonging to the same functional group. Finally, the immune responses elicited by the recombinant (r) Rv2041c protein were investigated using ex vivo and in vivo models of M. tb infection. A significantly high level of pro-inflammatory cytokines such as TNF-alpha, IL-6, and IL-12p40 was detected in a dose-dependent manner by treatment of murine bone marrow-derived macrophages with rRv2041c protein. In addition, IFN-gamma and TNF-alpha secretion increased after stimulation with purified Rv2041c protein to lymphocytes from latent and active TB mice in a modified Cornell model. In conclusion, our findings suggest that Rv2041c is a new T-cell antigen and could be a potential vaccine candidate against M. tb infection by inducing a strong cellular immune response.
Animals ; Anoxia ; Communicable Diseases ; Cytokines ; Hydrogen-Ion Concentration ; Immunity, Cellular ; Interleukin-12 Subunit p40 ; Interleukin-6 ; Latent Tuberculosis ; Lymphocytes ; Macrophages ; Mice ; Mycobacterium ; Mycobacterium tuberculosis ; Operon ; Proteins ; T-Lymphocytes ; Tuberculosis ; Tumor Necrosis Factor-alpha