Interferon Gamma Suppresses Collagen-Induced Arthritis by Regulation of Th17 through the Induction of Indoleamine-2,3-Deoxygenase

C57BL/6 mice are known to be resistant to the development of collagen-induced arthritis (CIA). However, they show a severe arthritic phenotype when the Ifng gene is deleted. Although it has been proposed that IFN-γ suppresses inflammation in CIA via suppressing Th17 which is involved in the pathogenesis of CIA, the exact molecular mechanism of the Th17 regulation by IFN-γ is poorly understood. This study was conducted to 1) clarify that arthritogenic condition of IFN-γ knockout (KO) mice is dependent on the disinhibition of Th17 and 2) demonstrate that IFN-γ-induced indoleamine2,3dioxgenase (IDO) is engaged in the regulation of Th17. The results showed that the IFN-γ KO mice displayed increased levels of IL-17 producing T cells and the exacerbation of arthritis. Also, production of IL-17 by the splenocytes of the IFN-γ KO mice was increased when cultured with type II collagen. When Il17 was deleted from the IFN-γ KO mice, only mild arthritis developed without any progression of the arthritis score. The proportion of CD44^highCD62L^low memory-like T cells were elevated in the spleen, draining lymph node and mesenteric lymph node of IFN-γ KO CIA mice. Meanwhile, CD44^lowCD62L^high naïve T cells were increased in IFN-γ and IL-17 double KO CIA mice. When Th17 polarized CD4+ T cells of IFN-γ KO mice were co-cultured with their own antigen presenting cells (APCs), a greater increase in IL-17 production was observed than in co-culture of the cells from wild type mice. In contrast, when APCs from IFN-γ KO mice were pretreated with IFN-γ, there was a significant reduction in IL-17 in the co-culture system. Of note, pretreatment of 1-methyl-DL- tryptophan, a specific inhibitor of IDO, abolished the inhibitory effects of IFN-γ. Given that IFN-γ is a potent inducer of IDO in APCs, these results suggest that IDO is involved in the regulation of IL-17 by IFN-γ.     

Characterizing antiviral mechanism of interleukin-32 and a circulating soluble isoform in viral infection

Interleukin-32 (IL-32) is an inflammatory cytokine, and its activity is associated with various auto-inflammatory disorders as well as infectious pathogens such as Mycobacterium tuberculosis, and viral infections. However, the precise antiviral mechanism of IL-32 remains unclear. We assessed the IL-32 level in the sera of H1N1 influenza A patients and IL-32 level was significantly elevated. Next we examined the antiviral activity of recombinant IL-32γ (rIL-32γ) with WISH cells infected by vesicular stomatitis virus (VSV) but no antiviral activity was observed. Therefore we investigated the supernatant of rIL-32-treated THP-1 cells since this cell line effectively responded to rIL-32γ. The supernatant of rIL-32-treated THP-1 cell possessed an antiviral effect and in addition, an agonistic monoclonal antibody further enhanced a specific antiviral activity of rIL-32γ. The fractionation and mass spectrometer analysis of the THP-1 cell supernatant revealed that the antiviral activity of rIL-32γ is via a THP-1 cell-produced factor, transferrin, rather than the direct effects of rIL-32γ on epithelial cells. We also characterized a secreted soluble IL-32γ protein in serum of IL-32γ transgenic mouse (TG), but not in that of IL-32α TG. The present results suggest that IL-32γ expression and its genetic variation in individual could be an important aspect of viral infections.     

Leucine zipper domain of HIV-1 gp41 interacted specifically with alpha-catenin

Interactions between viral and cellular proteins could explain the molecular mechanisms behind the viral life cycle of HIV-1. The envelope protein gp41 of HIV-1 specifically interacted with alpha-catenin, not with beta-catenin. This interaction was shown by in vitro protein assay and in vivo transfected cell systems. Microinjection of the DNA expressing HIV-1 gp160 and alpha-catenin, into the HeLa cell, resulted in the colocalization of gp41 and alpha-catenin. Interestingly the noncleavable mutant of gp160 and alpha-catenin were found to be colocalized in the cell membrane. Mapping of the interaction sites between these two proteins revealed that the leucine zipper-like structure, located between the first and second alpha-helix domains from the carboxy terminus of HIV-1 gp41, interacted strongly with the carboxy terminus of alpha-catenin.     

Contradictory functions (activation/termination) of neutrophil proteinase 3 enzyme (PR3) in interleukin-33 biological activity

IL-1 family ligand does not possess a typical hydrophobic signal peptide and needs a processing enzyme for maturation. The maturation process of IL-33 (IL-1F11), a new member of the IL-1 family ligand, remains unclear. Precursor IL-33 ligand affinity column isolates neutrophil proteinase 3 (PR3) from human urinary proteins. PR3 is a known IL-1 family ligand-processing enzyme for IL-1β (IL-1F2) and IL-18 (IL-1F4), including other inflammatory cytokines. We investigated PR3 in the maturation process of precursor IL-33 because we isolated urinary PR3 by using the precursor IL-33 ligand affinity column. PR3 converted inactive human and mouse precursor IL-33 proteins to biological active forms; however, the increase of PR3 incubation time abrogated IL-33 activities. Unlike caspase-1-cleaved precursor IL-18, PR3 cut precursor IL-33 and IL-18 at various sites and yielded multibands. The increased incubation period of PR3 abated mature IL-33 in a time-dependent manner. The result is consistent with the decreased bioactivity of IL-33 along with the increased PR3 incubation time. Six different human and mouse recombinant IL-33 proteins were expressed by the predicted consensus amino acid sequence of PR3 cleavage sites and tested for bioactivities. The human IL-33/p1 was highly active, but human IL-33/p2 and p3 proteins were inactive. Our results suggest the dual functions (activation/termination) of PR3 in IL-33 biological activity.     

Frequency and Fitness Consequences of Bacteriophage Φ6 Host Range Mutations

Viruses readily mutate and gain the ability to infect novel hosts, but few data are available regarding the number of possible host range-expanding mutations allowing infection of any given novel host, and the fitness consequences of these mutations on original and novel hosts. To gain insight into the process of host range expansion, we isolated and sequenced 69 independent mutants of the dsRNA bacteriophage Φ6 able to infect the novel host, Pseudomonas pseudoalcaligenes. In total, we found at least 17 unique suites of mutations among these 69 mutants. We assayed fitness for 13 of 17 mutant genotypes on P. pseudoalcaligenes and the standard laboratory host, P. phaseolicola. Mutants exhibited significantly lower fitnesses on P. pseudoalcaligenes compared to P. phaseolicola. Furthermore, 12 of the 13 assayed mutants showed reduced fitness on P. phaseolicola compared to wildtype Φ6, confirming the prevalence of antagonistic pleiotropy during host range expansion. Further experiments revealed that the mechanistic basis of these fitness differences was likely variation in host attachment ability. In addition, using computational protein modeling, we show that host-range expanding mutations occurred in hotspots on the surface of the phage''s host attachment protein opposite a putative hydrophobic anchoring domain.     

Impact of interleukin-21 in the pathogenesis of primary Sjogren's syndrome: increased serum levels of interleukin-21 and its expression in the labial salivary glands

Introduction

Interleukin (IL)-21 is a cytokine that controls the functional activity of effector T helper cells and the differentiation of Th17 cells, and promotes B-cell differentiation. To test whether IL-21 participates in the pathogenesis of primary Sjögren''s syndrome (SS), serum IL-21 level was measured and IL-21 expression in the labial salivary glands (LSG) was examined.

Methods

Serum IL-21 levels in 40 primary SS, 40 rheumatoid arthritis (RA), and 38 systemic lupus erythematosus (SLE) patients and 20 healthy controls were measured. Serum IL-21 levels of SS patients were assessed for correlations with laboratory data, including anti-nuclear antibody, anti-Ro/La antibodies, globulin, immunoglobulin (Ig) class, and IgG subclass. LSGs from 16 primary SS and 4 controls with sicca symptoms were evaluated for IL-21 and IL-21 receptor (IL-21R) expression by immunohistochemistry. Confocal microscopy was performed to further characterize the IL-21 positive cells.

Results

Primary SS patients had significantly higher serum IL-21 levels than controls, and these increments correlated positively with levels of IgG, IgG1. Serum IgG1 levels correlated with anti-Ro antibody titers. Immunohistochemical analyses showed that lymphocytic foci and the periductal area of the LSGs from SS patients expressed high levels of IL-21 and lower levels of IL-21R, whereas the control LSGs showed minimal expression of both antigens. The more the lymphocyte infiltrated, IL-21expression in LSGs showed a tendency to increase. Confocal microscopic analyses revealed that IL-21 expressing infiltrating lymphocytes in the LSGs of SS patients also expressed CXCR5.

Conclusions

Primary SS is associated with high serum IL-21 levels that correlate positively with serum IgG, especially IgG1, levels. The expression of IL-21 is increased as more lymphocytes infiltrated in LSGs. These observations suggest that IL-21 may play an important role in primary SS pathogenesis.     

Coenzyme Q10 Ameliorates Pain and Cartilage Degradation in a Rat Model of Osteoarthritis by Regulating Nitric Oxide and Inflammatory Cytokines

Objective

To investigate the effect of CoenzymeQ10 (CoQ10) on pain severity and cartilage degeneration in an experimental model of rat osteoarthritis (OA).

Materials and Methods

OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration of CoQ10 was initiated on day 4 after MIA injection. Pain severity was assessed by measuring secondary tactile allodynia using the von Frey assessment test. The degree of cartilage degradation was determined by measuring cartilage thickness and the amount of proteoglycan. The mankin scoring system was also used. Expressions of matrix metalloproteinase-13 (MMP-13), interleukin-1β (IL-1β), IL-6, IL-15, inducible nitric oxide synthase (iNOS), nitrotyrosine and receptor for advanced glycation end products (RAGE) were analyzed using immunohistochemistry.

Results

Treatment with CoQ10 demonstrated an antinociceptive effect in the OA animal model. The reduction in secondary tactile allodynia was shown by an increased pain withdrawal latency and pain withdrawal threshold. CoQ10 also attenuated cartilage degeneration in the osteoarthritic joints. MMP-13, IL-1β, IL-6, IL-15, iNOS, nitrotyrosine and RAGE expressions were upregulated in OA joints and significantly reduced with CoQ10 treatment.

Conclusion

CoQ10 exerts a therapeutic effect on OA via pain suppression and cartilage degeneration by inhibiting inflammatory mediators, which play a vital role in OA pathogenesis.     

A study on semantic web design for global national R&D status analysis

The analysis of global R&D information has become an important factor in making R&D investment strategies and global cooperation with the increased competition in the global market. The R&D analysis in Korea is based on the National Science and Technology Information Service (NTIS). However, it is limited to domestic information and the need to widen the analysis to the global market has risen recently. LOD (Linked Open Data) Cloud service, which is based on the openness and the connection of data, is being expanded recently as is the use of Mashup services through the connection with data from other institutes. In this paper, we will analyze the Linked data structure of CORDIS (Community Research and Development Information Service), which is the R&D information service adopted by the EU, and then suggest a case for utilizing the linked data format and design model for implementing the semantic web to effectively analyze the global national R&D trends by using a case where the RDF Triple data has been semantically mashed up from NTIS and NDSL (National Discovery for Science Leaders).     

Median Regression Model with Interval Censored Data

Quantile regression methods have been used to estimate upper and lower quantile reference curves as the function of several covariates. Especially, in survival analysis, median regression models to the right‐censored data are suggested with several assumptions. In this article, we consider a median regression model for interval‐censored data and construct an estimating equation based on weights derived from interval‐censored data. In a simulation study, the performances of the proposed method are evaluated for both symmetric and right‐skewed distributed failure times. A well‐known breast cancer data are analyzed to illustrate the proposed method.