Plasma N-Cleaved Galectin-9 Is a Surrogate Marker for Determining the Severity of COVID-19 and Monitoring the Therapeutic Effects of Tocilizumab.

Galectin-9 (Gal-9) is known to contribute to antiviral responses in coronavirus disease 2019 (COVID-19). Increased circulating Gal-9 in COVID-19 is associated with COVID-19 severity. In a while, the linker-peptide of Gal-9 is susceptible to proteolysis that can cause the change or loss of Gal-9 activity. Here, we measured plasma levels of N-cleaved-Gal9, which is Gal9 carbohydrate-recognition domain at the N-terminus (NCRD) with attached truncated linker peptide that differs in length depending on the type of proteases, in COVID-19. We also investigated the time course of plasma N-cleaved-Gal9 levels in severe COVID-19 treated with tocilizumab (TCZ). As a result, we observed an increase in plasma N-cleaved-Gal9 levels in COVID-19 and its higher levels in COVID-19 with pneumonia compared to the mild cases (healthy: 326.1 pg/mL, mild: 698.0 pg/mL, and with pneumonia: 1570 pg/mL). N-cleaved-Gal9 levels were associated with lymphocyte counts, C-reactive protein (CRP), soluble interleukin-2 receptor (sIL-2R), D-dimer, and ferritin levels, and ratio of percutaneous oxygen saturation to fraction of inspiratory oxygen (S/F ratio) in COVID-19 with pneumonia and discriminated different severity groups with high accuracy (area under the curve (AUC): 0.9076). Both N-cleaved-Gal9 and sIL-2R levels were associated with plasma matrix metalloprotease (MMP)-9 levels in COVID-19 with pneumonia. Furthermore, a decrease in N-cleaved-Gal9 levels was associated with a decrease of sIL-2R levels during TCZ treatment. N-cleaved-Gal9 levels showed a moderate accuracy (AUC: 0.8438) for discriminating the period before TCZ from the recovery phase. These data illustrate that plasma N-cleaved-Gal9 is a potential surrogate marker for assessing COVID-19 severity and the therapeutic effects of TCZ.

High Levels of the Cleaved Form of Galectin-9 and Osteopontin in the Plasma Are Associated with Inflammatory Markers That Reflect the Severity of COVID-19 Pneumonia.

Numbers of patients with coronavirus disease 2019 (COVID-19) have increased rapidly worldwide. Plasma levels of full-length galectin-9 (FL-Gal9) and osteopontin (FL-OPN) as well as their truncated forms (Tr-Gal9, Ud-OPN, respectively), are representative inflammatory biomarkers. Here, we measured FL-Gal9, FL-OPN, Tr-Gal9, and Ud-OPN in 94 plasma samples obtained from 23 COVID-19-infected patients with mild clinical symptoms (CV), 25 COVID-19 patients associated with pneumonia (CP), and 14 patients with bacterial infection (ID). The four proteins were significantly elevated in the CP group when compared with healthy individuals. ROC analysis between the CV and CP groups showed that C-reactive protein had the highest ability to differentiate, followed by Tr-Gal9 and ferritin. Spearman's correlation analysis showed that Tr-Gal9 and Ud-OPN but not FL-Gal9 and FL-OPN, had a significant association with laboratory markers for lung function, inflammation, coagulopathy, and kidney function in CP patients. CP patients treated with tocilizumab had reduced levels of FL-Gal9, Tr-Gal9, and Ud-OPN. It was suggested that OPN is cleaved by interleukin-6-dependent proteases. These findings suggest that the cleaved forms of OPN and galectin-9 can be used to monitor the severity of pathological inflammation and the therapeutic effects of tocilizumab in CP patients.

Possible role of plasma Galectin-9 levels as a surrogate marker of viremia in HIV infected patients on antiretroviral therapy in resource-limited settings.

BACKGROUND: Early detection of viremia in HIV infected patients on anti-retroviral therapy (ART) is important to prevent disease progression as well as accumulation of drug resistance mutations. This makes HIV viral load (VL) monitoring indispensable in HIV infected patients on ART. However VL, being an expensive test, results in heavy financial burden on health services. Hence, cheaper surrogate markers of viremia are desired to reduce overall cost of management of HIV infected patients. METHODS: We enrolled aviremic (n = 63, M:F = 31:32) and viremic (n = 43, M:F = 21:22) HIV infected patients at 1 year after ART initiation. Viremic individuals were identified as those having a plasma VL of more than 1000 copies/µl and aviremic individuals as less than 40 copies/µl. The study participants also included immuno-virologically discordant patients as they demonstrate differential degrees of immune-reconstitution and are likely to harbour concomitant infections influencing levels of immune-activation markers screened as the surrogate markers. Immune activation markers viz. plasma hs-CRP, soluble-CD14 and Galectin-9 levels were estimated by ELISA, IL-6 by luminex assay and percentages of CD38+ CD8+ cells were determined by flow cytometry. The levels were compared between viremic and aviremic patients and correlated with plasma viral load. Receiver operated curve (ROC) analysis was done for plasma Galectin-9 levels. RESULTS: Viremic patients had significantly higher levels of Galectin-9 and %CD38+ CD8+ cells (p values < 0.0001) than aviremic patients. Levels of the other activation markers did not differ between viremic and aviremic individuals. Galectin-9 levels (r = 0.76) and %CD38+ CD8+ cells (r = 0.39) correlated positively with VL. Area under curve for Galectin-9 levels for distinguishing between viremic and aviremic individuals was 0.98. Youden index, sensitivity, specificity, positive predictive value and negative predictive value for Galectin-9 levels were 0.87, 0.97, 0.90, 0.87 and 0.98, respectively, at the cut-off value of 5.79 ng/ml. CONCLUSIONS: Plasma Galectin-9 levels could identify viremic individuals with sensitivity and specificity of more than 90%. Thus, they showed a potential to serve as a surrogate marker of viremia in HIV infected patients on ART and would have cost implications on HIV management especially in resource-limited settings. However, the findings need to be confirmed in the patients on ART for different durations of time.

Stimulation of THP-1 Macrophages with LPS Increased the Production of Osteopontin-Encapsulating Exosome.

Osteopontin (OPN) mediates bone remodeling and tissue debridement. The OPN protein is cleaved, but it is unclear how full-length (FL)-OPN or its cleaved form perform their biological activities in target cells. We, therefore, performed the molecular characterization of OPN in exosomes (Exo). The Exo were isolated from lipopolysaccharide (LPS)-stimulated phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages. The Exo were also isolated from PMA-differentiated THP-1 macrophages. The Exo were identified using the qNano multiple analyzer (diameter 59-315 nm) and western blotting with a CD9 antibody. LPS-stimulated cells produced more particles than non-stimulated cells. The presence of the FL or the cleaved form of OPN was confirmed using western blot analysis. A mixture of FL and cleaved OPN was also measured using an ELISA system (Ud-OPN) and their presence in the Exo was confirmed. Ud/FL ratios became low after LPS stimulation, indicating the enhanced encapsulation of FL-OPN in the Exo by LPS. These findings suggest that LPS stimulation of human macrophages facilitates the synthesis of FL-OPN, which is cleaved in cells or the Exo after release. These findings indicate that Exo is a suitable vehicle to transfer OPN to the target cells.

Evaluation of a rapid diagnostic test for detection of dengue infection using a single-tag hybridization chromatographic-printed array strip format.

A dipstick DNA chromatography assay, a single-tag hybridization-printed array strip (STH-PAS), was evaluated for its efficacy to detect dengue virus (DENV). Reverse-transcribed DNA was amplified by PCR, and the amplified DNA was detected using the STH-PAS system. The method was evaluated using stored RNA samples previously identified to carry all 4 serotypes of dengue, chikungunya, and influenza viruses. Clinical performance was also assessed in a prospective study using plasma from 269 febrile cases from the Emergency Department of St. Luke's Medical Center, Quezon City, Philippines, and 30 afebrile normal healthy volunteers. A Taqman real-time PCR (RT-PCR) assay and a rapid Dengue NS1 test, SD Bioline, were used for comparison. The STH-PAS system was more sensitive in detecting dengue infection compared to Taqman RT-PCR. For DENV serotypes 1, 2, and 3, the detection was 1 to 2 dilutions (10-fold) higher, and for DENV serotype 4, the detection was 2-4 dilutions higher. In clinical studies, the STH-PAS system showed 100% sensitivity with 88.9% and 86.6% specificities compared to Taqman RT-PCR and SD Dengue Duo NS1 test, respectively. The STH-PAS system was found to have a superior sensitivity than the Taqman system. Further evaluation of its performance in the field may provide important data to extend its usefulness for surveillance and epidemiological research in outbreak situations.

Plasma Galectin-9 Concentrations in Normal and Diseased Condition.

BACKGROUND/AIMS: Galectin-9 is a soluble immune modulator with versatile functions, including a role as an immune checkpoint molecule. Therefore, the amount of galectin-9 in the blood may reflect an individual's immunological balance. Many studies have conducted galectin-9 measurements; however, the reported galectin-9 concentration in the blood varies greatly, even within healthy controls. This study investigates the variation between the reported and actual concentrations of galectin-9. METHODS: A GalPharma ELISA and an R&D Systems ELISA kit were directly compared using the same set of plasma and a series of recombinant galectins, including degraded galectin-9. Furthermore, galectin-9 in plasma was concentrated using anti-galectin-9 antibody-conjugated beads, and subjected to western blotting to estimate the quantity and integrity of galectin-9 and assess the consistency of ELISA measurements. RESULTS: The R&D Systems' ELISA indicated a 50-fold higher median concentration of plasma galectin-9 than that indicated by the GalPharma ELISA. This variation is due to aberrantly enhanced reactivity of the R&D Systems' ELISA to degraded galectin-9 present in small quantities in the plasma. The GalPharma ELISA could detect only intact galectin-9 and its results correlated well with the plasma galectin-9 level obtained by western blotting. CONCLUSION: ELISA kits from R&D Systems reacts aberrantly higher against degraded galectin-9 than the intact galectin-9. Therefore, the existence of a small amount of degraded galectin-9 in a test sample hinders the quantification. As galectin-9 is a fragile protein, this is a serious concern when using this kit. Based on quantifications from the GalPharma ELISA, the median (25th-75th percentiles) galectin-9 concentration in healthy subjects in the current study cohort was calculated as 110 pg/mL (67 -154 pg/mL).

Synthesis of a Cleaved Form of Osteopontin by THP-1 Cells and Its Alteration by Phorbol 12-Myristate 13-Acetate and BCG Infection.

The protease-cleaved osteopontin (OPN) was proposed to enhance the migration of memory T cells to granulomas in tuberculosis. Various forms of OPN were identified in human monocytic THP-1 cells stimulated by phorbol 12-myristate 13-acetate (PMA). Antibodies O-17, 10A16 and 34E3, which recognize N-terminus, the C-half, and thrombin-cleaved site of OPN, respectively, all detected distinct bands on Western blots following PMA stimulation. Bands corresponding to 18 and 30 kD were detected by antibodies 34E3 and 10A16, indicating that OPN cleavage occurred by endogenous proteases in the PMA-stimulated THP-1 cells. In immune-fluorescence (IF) assay, 34E3 positive signals were detected in intracellular space of non-infected and bacillus Calmette-Guérin (BCG)-infected cells; however, 10A16 positive signals were confirmed in extracellular area in PMA-stimulated cells followed by BCG infection. Small amounts of full-length (FL) and thrombin-cleaved (Tr) OPN were detected by ELISA in the supernatants of non-PMA-stimulated cells, and increased levels of all forms, including undefined (Ud) OPN, in PMA-stimulated cells. ELISA showed a decrease in OPN synthesis during BCG infection. To our knowledge, this is the first report of OPN cleavage in THP-1 macrophages after PMA stimulation, and of enhanced cleavage induced by BCG infection.

Comparison of antibody responses against Mycobacterium tuberculosis antigen Rv0679c in tuberculosis patients from the endemic and non-endemic regions of the Beijing genotype: a case control study.

BACKGROUND: Strains of the Beijing genotype of Mycobacterium tuberculosis (MTB) are reportedly associated with the virulence of tuberculosis (TB) infection, unfavorable outcomes of anti-TB treatment, and the global TB pandemic. Rv0679c, a hypothetical membrane protein related to host cell invasion, has a Beijing genotype-specific mutation at residue 142 (Asn142Lys). Antigenicity differences between Rv0679c-Asn142 (N-type) and Rv0679c-Lys142 (K-type) have been previously observed in mice antigen-antibody responses. However, the immune response to Rv0679c in humans remains unknown. Therefore, we aimed to investigate the anti-Rv0679c immune response in TB patients from the endemic and non-endemic regions of the Beijing MTB genotype. METHODS: We analyzed the Rv0679c-specific antibody responses in 84 subjects from the endemic region of the Beijing genotype MTB in China, including 45 pulmonary TB patients (C-PTB) and 39 healthy controls (C-HC), and 81 subjects from the Philippines (the endemic region of the non-Beijing genotype), including 51 pulmonary TB patients (P-PTB) and 30 healthy controls (P-HC). Anti-tuberculous-glycolipid (TBGL) antigen was used as the control antibody. RESULTS: TBGL IgG titers were higher in both C-PTB and P-PTB than those in their corresponding HC (C-PTB median 4.2, P-PTB median 11.2; C-PTB vs. P-PTB, p > 0.05), suggesting immune response comparability in PTB from two different countries. C-PTB showed a higher response compared to C-HC for anti-K-type IgG (53.3%) than anti-N-type IgG (6.67%); this response was not observed in P-PTB (both N-type and K-type 9.80%). CONCLUSION: Dimorphic antigen Rv0679c was found to be associated with distinct immune response patterns, indicating the role of Beijing/non-Beijing genotype of MTB in stimulating specific responses in TB patients from the endemic region of Beijing MTB. Meanwhile, reactions to Rv0679c in patients and HC from non-endemic regions of the Beijing MTB may be caused by the response to the common epitope of Rv0679c N/K-type.

Galectin-9 as a Predictive Marker for the Onset of Immune-Related Adverse Effects Associated with Anti-CCR4 MoAb Therapy in Patients with Adult T Cell Leukemia.

Adult T-cell leukemia/lymphoma (ATL/ATLL) is one of the most malignant lymphomas with poor prognosis. ATL/ATLL cells express CC chemokine receptor 4, and mogamulizumab (anti-CCR4 monoclonal antibody) exhibits strong cytotoxicity for ATL/ATLL cells. We analyzed plasma samples of 6 patients with ATL/ATLL treated with chemotherapy followed by mogamulizumab therapy (mogatherapy) for changes in the levels of biomarkers in relation to immune-related adverse effects. As treatment is often associated with skin eruptions, we investigated the profiles of inflammatory cytokines, including galectin-9 (Gal-9), which becomes increased in various infectious diseases and allergic patients. Gal-9, soluble interleukin (IL)-2 receptor, tumor necrosis factor-α, and IL-10 levels were increased before chemotherapy, and Gal-9 levels were associated with the sIL-2 receptor, which reflects tumor burden. Inflammatory levels decreased after chemotherapy. After mogatherapy, 5 of 6 patients attained complete remission (CR), whereas 1 patient showed no response (NR) and died. Among 5 patients with CR, the biomarkers remained low during mogatherapy, except for a 3-5-fold increment in Gal-9 (associated with skin eruptions). A skin biopsy showed infiltration by inflammatory cells and Gal-9 synthesis in areas with CD8 cell infiltration. In the patient with NR, increased levels of Gal-9 and the aforementioned biomarkers were noted 3 days after mogatherapy, followed by opportunistic infections resembling immune reconstitution inflammatory syndrome. Therefore, an increased Gal-9 plasma level in ATL/ATLL indicates tumor burden and reflects immune activation by mogatherapy. These findings may indicate that an increase in the Gal-9 level, a novel immune checkpoint molecule, can reflect immune-related adverse effects of various biotherapies.

Secretion of Galectin-9 as a DAMP during Dengue Virus Infection in THP-1 Cells.

Damage-associated molecular patterns (DAMPs) are endogenous cellular molecules released to the extracellular environment in response to stress conditions such as virus infection. Galectins are ß-galactoside-binding proteins that are widely expressed in cells and tissues of the immune system, are localized in the cell cytoplasm, and have roles in inflammatory responses and immune responses against infection. Elevated levels of galectin-9 (Gal-9) in natural human infections have been documented in numerous reports. To investigate the effect of dengue virus (DENV) infection on expression of endogenous Gal-9, monocytic THP-1 cells were infected with varying doses of DENV-3 (multiplicity of infection (MOI) 0.01, 0.03 and 0.1) and incubated at varying time points (Day 1, Day 2, Day 3). Results showed augmentation of Gal-9 levels in the supernatant, reduction of Gal-9 levels in the cells and decreased expression of LGALS9 mRNA, while DENV-3 mRNA copies for all three doses remained stable through time. Dengue virus induced the secretion of Gal-9 as a danger response; in turn, Gal-9 and other inflammatory factors, and stimulated effector responses may have limited further viral replication. The results in this pilot experiment add to the evidence of Gal-9 as a potential DAMP.

Secretion of IFN-γ Associated with Galectin-9 Production by Pleural Fluid Cells from a Patient with Extrapulmonary Tuberculosis.

In this study, we investigated the role of a matricellular protein galectin-9 (Gal-9) in pleural effusion related to tuberculosis (TB). Plasma and pleural fluid of a patient with extrapulmonary TB were analyzed for cytokine content by ELISA and Luminex. Peripheral blood mononuclear cells (PBMCs) and pleural fluid cells (PFCs) were examined for interferon-γ (IFN-γ) secretion by the enzyme-linked immunospot (ELISPOT) assay or IFN-γ ELISA, for apoptosis and necrosis by Cell Death Detection ELISA, and also underwent cell sorting. The results indicate that compared to plasma, pleural fluid had increased levels of IFN-γ (1.6 vs. 55.5 pg/mL), IL-10, IL-12p40, vascular endothelial growth factor (VEGF), and Gal-9 (3.0 vs. 936.0 pg/mL), respectively. PFCs culture supernatant exhibited higher concentration of Gal-9 compared to PBMCs in culture, consistent with enriched Gal-9 staining in the granuloma that is in closer vicinity to PFCs compared to PBMCs. PFCS displayed higher IFN-γ secretion after stimulation with TB antigens ESAT-6/CFP-10. Furthermore, in PFCs, Gal-9 alone could stimulate IFN-γ synthesis in culture or ELISPOT, which was inhibited by a Gal-9 antagonist lactose, and which may promote apoptosis and necrosis. These findings suggest that Gal-9 could modulate immune responses and participate in immunopathology of pleural effusion during TB.

Plasma levels of Galectin-9 reflect disease severity in malaria infection.

BACKGROUND: Galectin-9 (Gal-9) is a ß-galactoside-binding lectin that interacts with sugar moieties on glycoproteins and glycolipids of cells and pathogens. Gal-9 is known as an immune modulator that induces cell death via interaction with T cell immunoglobulin and mucin domain-3 (Tim3), a co-inhibitory receptor, and it inhibits production of several pro-inflammatory cytokines (TNF, IL-6 and IL-1α) and enhances production of IL-10. To understand the immune pathology of malaria, the Gal-9 in plasma was measured. METHODS: Plasma samples and clinical parameters were obtained from 50 acute malaria cases (nine severe and 41 uncomplicated cases) from Thailand at three time points: day 0, day 7 and day 28. Gal-9 levels were determined by ELISA. A total of 38 species of cytokines and chemokines were measured using a BioPlex assay. RESULTS: Gal-9 levels were higher at day 0 compared to day 7 and day 28 (P < 0.0001). Gal-9 levels were also higher in severe malaria (SM) cases compared to uncomplicated (UM) cases at day 0 and day 7 (923 vs 617 pg/mL; P = 0.03, and 659 vs 348 pg/mL; P = 0.02 respectively). Median Gal-9 levels were higher in patients with blood urea nitrogen to creatinine ratio (BUN/creatinine) ≥20 (mg/dL) than in patients with BUN/creatinine <20 (mg/dL) at day 0 (817.3 vs 576.2 pg/mL, P = 0.007). Gal-9 was inversely significantly correlated with chloride levels in both SM and UM cases (r s = -0.73 and r s = -0.46, respectively). In both UM and SM cases, Gal-9 was significantly associated with pro- and anti-inflammatory cytokines and chemokines such as TNF, IL-6, IFN-α2, IFN-γ, IL-1Ra and IL-10. These correlations were observed at day 0 but disappeared at day 28. CONCLUSIONS: Gal-9 is released during acute malaria, and reflects its severity. This elevation of Gal-9 in acute malaria infection raises the possibility of its role in termination of the immune response by binding to Tim-3, a receptor of Gal-9.

Persistently high prevalence of primary resistance and multidrug resistance of tuberculosis in Heilongjiang Province, China.

BACKGROUND: The spread of multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M. tuberculosis) strains has been a big challenge to the TB control and prevention in China. Knowledge about patterns of drug resistance in TB high-burden areas of China is crucial to develop appropriate control strategies. We conducted a comprehensive investigation of the resistance pattern of M. tuberculosis in Heilongjiang Province. METHODS: 1427 M. tuberculosis clinical strains were isolated from pulmonary TB patients hospitalized between 2007 and 2012. The susceptibility of the isolates to the first-line anti-TB drugs and the resistance of MDR M. tuberculosis to fluoroquinolones were examined. We also performed a statistical analysis to identify the correlated risk factors for high burden of MDR-TB. RESULTS: The global resistance rates of 2007-2012 to the first-line drugs and MDR were 57.0 and 22.8 %, respectively. Notably, the primary MDR-TB and pan-resistance rates were as high as 13.6 and 5.0 %, respectively. Of MDR M. tuberculosis isolates (2009), approximately 13 % were not susceptible to any of the fluoroquinolones tested. Being age of 35 to 54, high re-treatment proportion, the presence of cavity lesion, and high proportion of shorter hospitalization are correlated with the development of MDR-TB. CONCLUSIONS: The high prevalence of drug resistant, MDR-TB, and fluoroquinolone-resistant MDR-TB is a big concern for TB control. More importantly, in order to control the development of MDR-TB effectively, we need to pay more attention to the primary resistance. Targeting reducing the prevalence of the risk factors may lead to better TB control in China.

Prevention of Tetanus Outbreak Following Natural Disaster in Indonesia: Lessons Learned from Previous Disasters.

In Indonesia, the Aceh earthquake and tsunami in 2004 killed 127,000 people and caused half a million injuries, while the Yogyakarta earthquake in 2006 caused 5,700 deaths and 37,000 injuries. Because disaster-affected areas are vulnerable to epidemic-prone diseases and tetanus is one such disease that is preventable, we systematically reviewed the literature related to tetanus outbreaks following previous two natural disasters in Indonesia. Based on our findings, recommendations for proper vaccination and education can be made for future countermeasures. Using specified keywords related to tetanus and disasters, relevant documents were screened from PubMed, the WHO website, and books. Reports offering limited data and those released before 2004 were excluded. In all, 16 publications were reviewed systematically. Results show that 106 cases of tetanus occurred in Aceh, with a case fatality ratio (CFR) of 18.9%; 71 cases occurred in Yogyakarta, with CFR of 36.6%. For both outbreaks, most patients had been wounded during scavenging or evacuation after the disaster occurred. Poor access to health care because of limited transportation or hospital facilities, and low vaccination coverage and lack of awareness of tetanus risk contributed to delayed treatment and case severity. Tetanus outbreaks after disasters are preventable by increasing vaccination coverage, improving wound care treatment, and establishing a regular surveillance system, in addition to good practices of disaster management and supportive care following national guidelines. Furthermore, health education for communities should be provided to raise awareness of tetanus risk reduction.

Development of Point-of-Care Testing for Disaster-Related Infectious Diseases.

After disaster, the victims lose their safe lives and are even exposed to nature where they could suffer from animal bites and vectors followed by suffering from zoonosis or vector-born diseases. Because of the urgent need for rapid and cheap diagnosis for infectious diseases after disaster, anonymous questionnaire clarified that leptospirosis, dengue, diarrhea, and cholera were recognized as common disaster-related infections in the Philippines, while diarrhea and pneumonia were more common in Indonesia. It should also be noted that infectious disease itself such as tuberculosis associated with acquired immune deficiency syndrome in South Africa is a disaster. Thus, the possible occurrence of similar situation in Asia should be prevented. We have conducted an international collaborative research in the Philippines and Indonesia on dengue virus, leptospira and mycobacterium tuberculosis (MTB) infectious diseases. Development of point-of-care testing for molecular diagnosis and disease severity was the principal purpose of the research. Loop-mediated isothermal amplification assay, which does not require a source of electricity, was developed for leptospirosis, dengue and MTB and has been proved to be useful where resource is limited. The plasma levels of matricellular proteins, including galectin-9 and osteopontin, were found to reflect the disease severities in dengue virus and MTB infection, probably because matricellular proteins are one of the most functional extracellular proteins that are associated with inflammatory edema. The study on disaster-related infectious disease facilitates the international cooperation for development of point-of-care testing for tropical infectious diseases.

Immunological Roles of Elevated Plasma Levels of Matricellular Proteins in Japanese Patients with Pulmonary Tuberculosis.

Elevated matricellular proteins (MCPs), including osteopontin (OPN) and galectin-9 (Gal-9), were observed in the plasma of patients with Manila-type tuberculosis (TB) previously. Here, we quantified plasma OPN, Gal-9, and soluble CD44 (sCD44) by enzyme-linked immunosorbent assay (ELISA), and another 29 cytokines by Luminex assay in 36 patients with pulmonary TB, six subjects with latent tuberculosis (LTBI), and 19 healthy controls (HCs) from Japan for a better understanding of the roles of MCPs in TB. All TB subjects showed positive results of enzyme-linked immunospot assays (ELISPOTs). Spoligotyping showed that 20 out of 36 Mycobacterium tuberculosis (MTB) strains belong to the Beijing type. The levels of OPN, Gal-9, and sCD44 were higher in TB (positivity of 61.1%, 66.7%, and 63.9%, respectively) than in the HCs. Positive correlations between OPN and Gal-9, between OPN and sCD44, and negative correlation between OPN and ESAT-6-ELISPOT response, between chest X-ray severity score of cavitary TB and ESAT-6-ELISPOT response were observed. Instead of OPN, Gal-9, and sCD44, cytokines G-CSF, GM-CSF, IFN-α, IFN-γ, IL-12p70, and IL-1RA levels were higher in Beijing MTB-infected patients. These findings suggest immunoregulatory, rather than inflammatory, effect of MCPs and can advance the understanding of the roles of MCPs in the context of TB pathology.

Urine Levels of Defensin α1 Reflect Kidney Injury in Leptospirosis Patients.

Leptospirosis is a zoonotic disease whose severe forms are often accompanied by kidney dysfunction. In the present study, urinary markers were studied for potential prediction of disease severity. Urine samples from 135 patients with or without leptospirosis at San Lazaro Hospital, the Philippines, were analyzed. Urine levels of defensin α1 (uDA1) were compared with those of neutrophil gelatinase-associated lipocalin (uNGAL) and N-acetyl-ß-d-glucosidase (uNAG). Serum creatinine (Cr) was used as a marker of kidney injury. The levels of uDA1/Cr, uNGAL/Cr, and uNAG/Cr were positive in 46%, 90%, and 80% of leptospirosis patients, and 69%, 70%, and 70% of non-leptospirosis patients, respectively. In leptospirosis patients, the correlation of uDA1/Cr, uNGAL/Cr and uNAG/Cr levels with serum Cr were r = 0.3 (p < 0.01), r = 0.29 (p < 0.01), and r = 0.02 (p = 0.81), respectively. uDA1/Cr levels were correlated with uNGAL/Cr levels (r = 0.49, p < 0.01) and uNAG/Cr levels (r = 0.47, p < 0.0001) in leptospirosis patients. These findings suggest that uDA1, uNGAL, and uNAG were elevated in leptospirosis patients and reflected various types of kidney damage. uDA1 and uNGAL can be used to track kidney injury in leptospirosis patients because of their correlation with the serum Cr level.

Osteopontin-integrin interaction as a novel molecular target for antibody-mediated immunotherapy in adult T-cell leukemia.

BACKGROUND: Adult T-cell leukemia (ATL) is a CD4(+) T-cell neoplasm with a poor prognosis. A previous study has shown that there is a strong correlation between the secreted matricellular protein osteopontin (OPN) level and disease severity in ATL patients. Here, we investigated the role of OPN in ATL pathogenesis and the possible application of anti-OPN monoclonal antibody (mAb) for ATL immunotherapy in NOD/Shi-scid,IL-2Rg (null) (NOG) mice. RESULTS: Subcutaneous inoculation of ATL cell lines into NOG mice increased the plasma level of OPN, which significantly correlated with metastasis of the inoculated cells and survival time. Administration of an SVVYGLR motif-recognizing anti-OPN mAb resulted in inhibition not only of tumor growth but also of tumor invasion and metastasis. The number of fibroblast activating protein-positive fibroblasts was also reduced by this mAb. We then co-inoculated mouse embryonic fibroblasts (MEFs) isolated from wild-type (WT) or OPN knockout mice together with ATL-derived TL-OmI cells into the NOG mice. The mice co-inoculated with WT MEFs displayed a significant decrease in survival relative to those injected with TL-OmI cells alone and the absence of OPN in MEFs markedly improved the survival rate of TL-OmI-inoculated mice. In addition, tumor volume and metastasis were also reduced in the absence of OPN. CONCLUSION: We showed that the xenograft NOG mice model can be a useful system for assessment of the physiological role of OPN in ATL pathogenesis. Using this xenograft model, we found that fibroblast-derived OPN was involved in tumor growth and metastasis, and that this tumor growth and metastasis was significantly suppressed by administration of the anti-OPN mAbs. Our findings will lead to a novel mAb-mediated immunotherapeutic strategy targeting against the interaction of OPN with integrins on the tumor of ATL patients.

Evaluation of matricellular proteins in systemic and local immune response to Mycobacterium tuberculosis infection.

Matricellular proteins such as osteopontin (OPN), galectin-9 (Gal-9), and tenascin-C (TN-C) are expressed not only under normal physiological conditions, but also during infection, inflammation and tumorigenesis. Plasma concentrations of matricellular proteins were studied to determine their diagnostic value as potential markers of tuberculosis (TB) activity. It was found that concentrations of OPN and TN-C were higher in patients with active TB than in healthy controls and individuals with latent infection. Moreover, LTBI patients had higher concentrations of OPN than did healthy controls. Gal-9 concentrations did not differ significantly between groups. Concentrations of matricellular proteins were higher in pleural fluid than in the plasma of patients with TB. Expression of matricellular proteins was also investigated in TB granulomas and other granulomatous diseases. Positive OPN and Gal-9 staining was observed in TB and sarcoidosis granulomas, but not in Crohn disease granulomas. The fibrotic ring around granulomas stained positive for TN-C in TB and sarcoidosis, but not in Crohn disease. Of the three matricellular proteins studied, OPN and TN-C may serve as reliable plasma markers for monitoring TB activity, whereas Gal-9 seems to be expressed more at the site of infection than in the systemic circulation.

Gene Expression Profiling of IL-17A-Treated Synovial Fibroblasts from the Human Temporomandibular Joint.

Synovial fibroblasts contribute to the inflammatory temporomandibular joint under pathogenic stimuli. Synovial fibroblasts and T cells participate in the perpetuation of joint inflammation in a mutual activation feedback, via secretion of cytokines and chemokines that stimulate each other. IL-17 is an inflammatory cytokine produced primarily by Th17 cells which plays critical role in the pathogenesis of numerous autoimmune and inflammatory diseases. Here, we investigated the roles of IL-17A in temporomandibular joint disorders (TMD) using genome-wide analysis of synovial fibroblasts isolated from patients with TMD. IL-17 receptors were expressed in synovial fibroblasts as assessed using real-time PCR. Microarray analysis indicated that IL-17A treatment of synovial fibroblasts upregulated the expression of IL-6 and chemokines. Real-time PCR analysis showed that the gene expression of IL-6, CXCL1, IL-8, and CCL20 was significantly higher in IL-17A-treated synovial fibroblasts compared to nontreated controls. IL-6 protein production was increased by IL-17A in a time- and a dose-dependent manner. Additionally, IL-17A simulated IL-6 protein production in synovial fibroblasts samples isolated from three patients. Furthermore, signal inhibitor experiments indicated that IL-17-mediated induction of IL-6 was transduced via activation of NFκB and phosphatidylinositol 3-kinase/Akt. These results suggest that IL-17A is associated with the inflammatory progression of TMD.