Inhibition of the TIM-1 and -3 signaling pathway ameliorates disease in a murine model of rheumatoid arthritis.

Members of the T-cell immunoglobulin and mucin (TIM) family, which is crucial for T-cell function, are implicated in autoimmunity. TIM-1 and -3 play distinct roles in autoimmunity, with TIM-1 acting as a costimulatory molecule and TIM-3 regulating Th1 responses. We investigated the therapeutic potential of anti-TIM-1 (RMT1-10) and anti-TIM-3 (RMT3-23) antibodies in an autoimmune arthritis model. Zymosan A was used to induce arthritis in female SKG mice. The arthritis scores, histology, mRNA expression, cytokine levels, micro-computed tomography, and flow cytometry results were obtained. The application of RMT1-10 reduced the arthritis scores, histological damage, and CD4+ T-cell infiltrations, and it suppressed interleukin (IL)-6 and -17A and reduced TIM-3 mRNA expressions. RMT3-23 also lowered arthritis severity, improved histology, and reduced serum levels of tumor necrosis factor (TNF)-α and IL-17A. RMT3-23 inhibited intracellular TNF-α and IL-6 and early apoptosis. An amelioration of autoimmune arthritis was achieved by blocking the TIM-1 and -3 signaling pathways via RMT1-10 and RMT3-23 administration, leading to a widespread decrease in inflammatory cytokines. Both antibodies exhibited therapeutic effects, suggesting TIM-1 and -3 as potential targets for rheumatoid arthritis.

The relationship between the initial pH and neurological outcome in patients with out-of-hospital cardiac arrest is affected by the status of recovery of spontaneous circulation on hospital arrival.

The early prediction of neurological outcomes is useful for out-of-hospital cardiac arrest (OHCA). The initial pH was associated with neurological outcomes, but the values varied among the studies. Patients admitted to our division with OHCA of cardiac origin between January 2015 and December 2022 were retrospectively examined (N = 199). A good neurological outcome was defined as a Glasgow-Pittsburgh cerebral performance category (CPC) of 1-2 at discharge. Patients were divided according to the achievement of recovery of spontaneous circulation (ROSC) on hospital arrival, and the efficacy of pH in predicting good neurological outcomes was compared. In patients with ROSC on hospital arrival (N = 100), the initial pH values for good and poor neurological outcomes were 7.26 ± 0.14 and 7.09 ± 0.18, respectively (p < 0.001). In patients without ROSC on hospital arrival (N = 99), the initial pH values for good and poor neurological outcomes were 7.06 ± 0.23 and 6.92 ± 0.15, respectively (p = 0.007). The pH associated with good neurological outcome was much lower in patients without ROSC than in those with ROSC on hospital arrival (P = 0.003). A higher initial pH is associated with good neurological outcomes in patients with OHCA. However, the pH for a good or poor neurological outcome depends on the ROSC status on hospital arrival.

U-KIM-1 as a predictor of treatment response in lupus nephritis.

OBJECTIVE: Biomarkers of disease activity in lupus nephritis (LN) are in demand. This is because they may be useful in patients who are unable to undergo invasive kidney biopsy, as predictors of renal function, and for early detection of LN recurrence. The focus is on the measurement of urinary chemokines and cytokines, especially in urinary biomarkers, which are non-invasive and simple. In our previous report, we reported that kidney injury molecule-1 (KIM-1) is expressed in injured tubules and that the number of tubular-KIM-expressing positive cells correlates with renal pathology findings and also with urinary (u)-KIM-1 levels. However, there have been no reports examining the effect of u-KIM-1 levels on response to therapy, correlation with renal pathology, and usefulness as a predictor of renal function. METHODS: U-KIM-1 levels were measured by ELISA in 61 SLE patients. In 38 active LN who underwent renal biopsy, we also examined whether u-KIM-1 levels affected LN disease activity, renal histological findings, and predictors of renal function. RESULTS: In SLE patients, proteinuria and u-KIM-1 levels were elevated in active LN compared to inactive LN. U-KIM-1 and proteinuria decreased with intensified treatment. U-KIM-1 levels also correlated with the percentage of glomerular crescent formation in renal pathology. In addition, patients with higher baseline u-KIM-1 levels had significantly higher eGFR and lower LN disease activity at 12 months after treatment intensification. CONCLUSIONS: These data suggest that u-KIM-1 levels correlate with LN disease activity and renal histopathology findings and may be used as a predictor of treatment response.

Iguratimod versus salazosulfapyridine in rheumatoid arthritis patients with an inadequate response to methotrexate: Adjusted with propensity score matching.

OBJECTIVES: Methotrexate (MTX) is recommended as a first-line conventional synthetic disease-modifying antirheumatic drug (csDMARD) for treating rheumatoid arthritis (RA). This retrospective study sought to identify an add-on csDMARD treatment strategy for RA patients with MTX-inadequate response (IR). METHODS: We collected the cases of RA patients treated with salazosulfapyridine (SASP) or iguratimod (IGU) as the additional csDMARD for MTX-IR during a 24-month follow-up. We performed propensity score matching to evaluate the retention rate, clinical efficacy, and safety profile (n = 54, each group). RESULTS: The retention rates at 24 months were 38.5% (MTX+SASP group) and 67.8% (MTX+IGU group). At 3 and 6 months, the MTX+IGU group's 28 joint-disease activity score (DAS28) was significantly decreased versus the MTX+SASP group, and at 3 months the MTX+IGU group's good-responder percentage (22.9%) was significantly higher versus the MTX+SASP group's good-responder percentage (10.7%). Conversely, compared to the MTX+SASP group, the MTX+IGU group showed a greater reduction in the estimated glomerular filtration rate from baseline during follow-up. CONCLUSIONS: IGU is a useful add-on csDMARD for RA patients with MTX-IR; its high retention rate and good clinical response make it a useful combination therapy for controlling RA disease activity. However, the renal function should be monitored during follow-up.

Deletion of Antigen-Presenting Cells in Lipopolysaccharide-Induced Acute Kidney Injury (AKI) Affects the Exacerbation and Repair in AKI.

The pathogenesis of acute kidney injury (AKI) is complex and involves various immune and inflammatory responses. Antigen-presenting cells such as macrophages and dendritic cells (DCs) were recently reported to have diverse functions in AKI depending on the pathogenesis and disease phase. Herein, we intraperitoneally administered liposomal clodronate (LC) to lipopoly-saccharide (LPS)-induced AKI model mice in order to deplete antigen-presenting cells (e.g., macrophages and DCs). After the LPS injection, the mice were divided into LC-treated (LPS + LC) and saline-treated groups (LPS), and the immune responses of macrophages and DCs in the acute and recovery phases were evaluated. The LPS + LC-treated group exhibited significantly suppressed renal macrophages and DC infiltration at 18 h and improved survival at 120 h after LPS injection. Via the depletion of macrophages and DC infiltrations, the serum and renal tissue inflammatory cytokines/chemokines were suppressed at 18 h and reversed at 120 h. Tubular kidney injury molecule-1 expression was decreased at 18 h and increased at 120 h. These findings indicate that LC administration suppressed tubular and interstitial injury in the acute phase of AKI and affected delayed tissue repair in the recovery phase. They are important for understanding innate and acquired immune responses in the therapeutic strategy for LPS-induced AKI.

Fatal outcome in a patient under immunosuppressant therapy infected with human T-lymphotropic virus type 1 (HTLV-1), cytomegalovirus (CMV) and Strongyloides stercoralis: a case report.

BACKGROUND: Strongyloidiasis is a gastrointestinal parasitic infection caused by percutaneous infection with Strongyloides stercoralis. Digestive symptoms such as diarrhea and abdominal pain are the main manifestation, but serious infections such as septicemia, purulent meningitis, and bacterial pneumonia may occur in individuals harboring human T-lymphotropic virus type 1 (HTLV-1) or who are immunocompromised. Although coinfection with Strongyloides stercoralis and HTLV-1 can lead to chronic strongyloidiasis and a disseminated form of the disease, there is a high rate of response to the anthelmintic ivermectin. CASE PRESENTATION: We report a case of strongyloidiasis infection syndrome that was difficult to differentiate from immune reconstitution inflammatory syndrome (IRIS) for various reasons. The patient had been treated with the corticosteroids tacrolimus (Tac) and mycophenolate mofetil (MMF) for systemic lupus erythematosus (SLE) with lupus nephritis and pancytopenia. When the steroid was reduced, she developed cytomegalovirus (CMV) enteritis, and her respiratory status rapidly deteriorated immediately after the withdrawal of Tac and MMF. It was difficult to distinguish immune reconstitution inflammatory syndrome from strongyloidiasis infection syndrome because stool cultures were negative and eosinophils were not increased. Bronchoscopy revealed viable Strongyloides, leading to a diagnosis of strongyloidiasis infection syndrome, but the patient died despite treatment. CONCLUSIONS: Both corticosteroid therapy and HTLV-1 infection can be associated with a decrease of eosinophils, despite the presence of parasitic infection. In conclusion, even if multiple culture tests are negative, the risk of parasitic infection should be assessed in patients receiving immunosuppressants and steroids even in non-endemic areas.

A case of planar-type GIST of the sigmoid colon showing diverticular structure with perforation.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) generally form well-defined mass lesions. However, some cases of the flatly distributed and muscularis propria-replacing GISTs have been reported so far. We experienced an additional case of planar-type GIST of the sigmoid colon accompanied by a diverticulum with perforation. CASE PRESENTATION: A 68-year-old Japanese male with sudden onset of abdominal pain was clinically diagnosed with gastrointestinal perforation, and an emergency abdominal operation was performed. A diverticulum with rupture was found in the sigmoid colon, but no apparent tumor was observed. Histological examination revealed bland spindle cells flatly proliferating and diffusely replacing the muscularis propria at the diverticular structure. The spindle cells were positive for KIT, DOG1, and CD34. Mutational analysis of the c-kit gene revealed that the lesion had a heterozygous deletion of 2 amino acids at codons 557 and 558 of exon 11. The mutation was not observed in the normal mucosa of the surrounding tissue. CONCLUSION: We diagnosed this case as an unusual planar-type GIST. Some similar cases have been reported in the sigmoid colon and other sites. We discuss the mechanism of development of the planar-type GISTs associated with the diverticulum.

Efficacy of iguratimod vs. salazosulfapyridine as the first-line csDMARD for rheumatoid arthritis.

Objectives: We retrospectively evaluated the retention rate and clinical responses following treatment for rheumatoid arthritis (RA) with iguratimod (IGU) vs. salazosulfapyridine (SASP) as the first-line conventional synthetic disease-modifying antirheumatic drug (csDMARD).Methods: We analyzed 197 RA patients who were treated with IGU or SASP as the initial treatment in the 3-year study period. The retention rate, clinical response, the dosage and percent user of prednisolone (PSL), and safety profiles were evaluated.Results: At month 36, the retention rates of the IGU and SASP groups were 52.4 vs. 32.1%. The rate of responders (good or moderate response) at month 36 was 85.8 vs. 65.2% in the IGU and SASP groups, respectively. At month 36 for the IGU and SASP groups, the percentages of PSL users were 16.7 vs. 46.7%, and the PSL dosage was 0.3 mg/d vs. 2.0 mg/d, respectively. The cumulative rates of any adverse event (AE) at month 36 were 19.8 vs. 29.2% in the IGU and SASP groups, respectively.Conclusion: IGU is a useful first-line csDMARD treatment for RA patients, showing a high retention rate and good efficacy without an increased risk of serious AEs, including serious infections. Our findings also indicate a PSL dose-sparing effect of IGU treatment.

Protective effect and mechanism of IL-10 on renal ischemia-reperfusion injury.

Interleukin (IL)-10, a cytokine with anti-inflammatory effects, is produced by blood cells and cells of various organs. Ischemia-reperfusion injury (IRI) is a systemic inflammatory disease caused by a systemic circulation of pro-inflammatory cytokines and chemokines produced from blood cells or organs damaged by ischemia. Apoptosis, a key event after IRI, is correlated with the degree of injury. Here we investigated the effects and mechanism of IL-10 in renal IRI. Compared to wild-type (WT) mice with a renal IRI, IL-10 knockout (IL-10 KO) mice with IRI demonstrated decreased renal function as represented by blood urea nitrogen and serum creatinine, upregulated early acute kidney injury (AKI) biomarkers such as kidney injury molecule-1 (Kim-1), increased mRNA expression of the pro-inflammatory cytokines IL-1ß, IL-6, and IL-18 and a chemokine (regulated on activation, normal T cell expressed and secreted; RANTES), and increased expression of the pro-apoptosis factors Bax and cleaved caspase-3. When tubular epithelial cells (TECs) from IL-10 KO mice were put in a hypoxic state and added with recombinant IL-10, their expression of Bax decreased. Our findings demonstrated that IL-10 suppressed the production of pro-inflammatory cytokines, renal dysfunction, and the expression of pro-apoptosis factors after IRI.

Manipulating Single Microdroplets of NaCl Solutions: Solvent Dissolution, Microcrystallization, and Crystal Morphology.

A new "three-micropipette manipulation technique" for forming, dehydrating, crystallizing, and resolvating nanograms of salt material has been developed to study supersaturated single microdroplets and microcrystals. This is the first report of studies that have measured in situ both supersaturation (as homogeneous nucleation) and saturation (as microcrystal redissolution) for single microdroplets of NaCl solution using the micropipette technique. This work reports a measure of the critical supersaturation concentration for homogeneous nucleation of NaCl (10.3 ± 0.3 M) at a supersaturation fraction of S = 1.9, the saturation concentration of NaCl in aqueous solution as measured with nanograms of material (5.5 ± 0.1 M), the diffusion coefficient for water in octanol, D = (1.96 ± 0.10) × 10-6 cm2/s, and the effect of the solvent's activity on dissolution kinetics. It is further shown that the same Epstein-Plesset (EP) model, which was originally developed for diffusion-controlled dissolution and uptake of gas, and successfully applied to liquid-in-liquid dissolution, can now also be applied to describe the diffusion-controlled uptake of water from a water-saturated environment using the extended activity-based model of Bitterfield et al. This aspect of the EP model has not previously been tested using single microdroplets. Finally, it is also reported how the water dissolution rate, rate of NaCl concentration change, resulting crystal structure, and the time frame of initial crystal growth are affected by changing the bathing medium from octanol to decane. A much slower loss of water-solvent and concomitant slower up-concentration of the NaCl solute resulted in a lower tendency to nucleate and slower crystal growth because much less excess material was available at the onset of nucleation in the decane system as compared to the octanol system. Thus, the crystal structure is reported to be dendritic for NaCl solution microdroplets dissolving rapidly and nucleating violently in octanol, while they are formed as single cubic crystals in a gentler way for solution-dissolution in decane. These new techniques and analyses can now also be used for any other system where all relevant parameters are known. An example of this is control of drug/hydrogel/emulsion particle size change due to solvent uptake.

Micropipette Technique Study of Natural and Synthetic Lung Surfactants at the Air-Water Interface: Presence of a SP-B Analog Peptide Promotes Membrane Aggregation, Formation of Tightly Stacked Lamellae, and Growth of Myelin Figures.

The present study is a microscopic interfacial characterization of a series of lung surfactant materials performed with the micropipette technique. The advantages of this technique include the measurement of equilibrium and dynamic surface tensions while acquiring structural and dynamic information at microscopic air-water interfaces in real time and upon compression. Here, we characterized a series of animal-derived and synthetic lung surfactant formulations, including native surfactant obtained from porcine lungs (NS); the commercial Curosurf, Infasurf, and Survanta; and a synthetic Super Mini-B (SMB)-containing formulation. It was observed that the presence of the natural hydrophobic proteins and, more strikingly, the peptide SMB, promoted vesicle condensation as thick membrane stacks beneath the interface. Only in the presence of SMB, these stacks underwent spontaneous structural transformations, consisting of the nucleation and growth of microtubes and in some cases their subsequent coiling into helices. The dimensions of these tubes (2-15 µm diameter) and their linear (2-3 µm/s) and volumetric growth rates (20-30 µm3/s) were quantified, and no specific effects were found on them for increasing SMB concentrations from 0.1 to 4%. Nevertheless, a direct correlation between the number of tubes and SMB contents was found, suggesting that SMB molecules are the promoters of tube nucleation in these membranes. A detailed analysis of the tube formation process was performed following previous models for the growth of myelin figures, proposing a combined mechanism between dehydration-rehydration of the lipid bilayers and induction of mechanical defects by SMB that would act as nucleation sites for the tubes. The formation of tubes was also observed in Infasurf, and in NS only after subsequent expansion and compression but neither in the other clinical surfactants nor in protein-free preparations. Finally, the connection between this data and the observations from the lung surfactant literature concerning the widely reported "near-zero surface tension" for lung surfactant films and intact alveolar surfaces is also discussed.

Estimation of the symptoms for GERD by GerdQ in the patients with rheumatic diseases.

OBJECTIVE: Gastroesophageal reflux disease (GERD) is one of the most common comorbidity in many diseases, but the frequency in rheumatic disease has not been well understood. METHODS: We investigated the prevalence of GERD by GerdQ in 530 rheumatic patients [systematic lupus erythematosus (SLE; n = 120), rheumatoid arthritis (RA; n = 117), polymyalgia rheumatica (PMR; n = 40), dermatomyositis and polymyositis (PM/DM; n = 38), systemic scleroderma (SSc; n = 37), mixed connective tissue disease (MCTD; n = 18), Behçet disease (BD; n = 17), adult onset still disease (AOSD; n = 14), and other rheumatic diseases (n = 129)]. RESULTS: The mean GerdQ scores of patients was 6.2 ± 1.8, respectively, and no significant differences were observed between all patients. However, the GERD prevalence in SSc and BD was increased compared to that in SLE, RA, PMR, PM/DM, MCTD, and AOSD. In no medication of proton pump inhibitors (PPIs), a significant increase in the risk of GERD symptoms was 2.5 times compared with that in the medication of PPIs in all patients by multivariable regression analysis. On the other hand, there were no increased risks of GERD symptoms with corticosteroids. CONCLUSION: In rheumatic diseases, GerdQ would be the useful tool of diagnosis GERD, regardless whether the patients complain or not about gastrointestinal (GI) symptoms.

Signaling Rho-kinase mediates inflammation and apoptosis in T cells and renal tubules in cisplatin nephrotoxicity.

Nephrotoxicity is a frequent complication of cisplatin-induced chemotherapy, in which T cells are known to promote acute kidney injury (AKI). Apoptosis and necrosis of tubules and inflammatory events also contribute to the nephrotoxicity. A delineation of the mechanisms that underlie the inappropriate renal and tubular inflammation can thus provide important insights into potential therapies for cisplatin-induced AKI. Rho-kinases are known to act as molecular switches controlling several critical cellular functions, including cell migration, cytokine production, and apoptosis. Here, we show that the Rho-kinase inhibitor fasudil attenuated cisplatin nephrotoxicity, resulting in less histological damage, improved renal function, and the infiltration of fewer leukocytes into the kidney. Renal nuclear factor-κB activation and apoptosis were reduced, and the expressions of proinflammatory renal cytokine and chemokine mRNA were decreased. Urinary and renal kidney injury molecule-1 (Kim-1) expression was also reduced, a finding that is consistent with diminished kidney injury. In the current study, we also showed that fasudil could be protective of the impaired tubules. In vitro, fasudil reduced the apoptosis (annexin-V+PI cells) and cytokine production (tumor necrosis factor+ cells) in T cells and the apoptosis (annexin-V+PI cells) and tubular damage (Kim-1+ cells) in proximal tubular cells by flow cytometric analysis. As Rho-kinase plays an important role in promoting cisplatin nephrotoxicity, inhibiting Rho-kinase may be a therapeutic strategy for preventing cisplatin-induced AKI.

The pathological role of IL-18Rα in renal ischemia/reperfusion injury.

Interleukin (IL)-18 is a proinflammatory cytokine produced by leukocytes and parenchymal cells (eg, tubular epithelial cells (TECs), mesangial cells, and podocytes). IL-18 receptor (IL-18R) is expressed on these cells in the kidney during ischemia/reperfusion injury (IRI), but its role in this injury is unknown. Fas/Fas ligand (FasL) is also involved in the pathogenesis of renal IRI via tubular apoptosis. In addition, IL-18 enhances the expression of FasL on TECs, but the mechanism underlying this enhancement is not known. Here we used IL-18Rα-deficient mice to explore the pathological role of IL-18Rα in renal IRI. We found that compared to wild-type (WT) mice with renal IRI as an acute kidney injury (AKI), the IL-18Rα-deficient mice demonstrated decreased renal function (as represented by blood urea nitrogen), tubular damage, an increased accumulation of leukocytes (CD4+ T cells, neutrophils, and macrophages), upregulated early AKI biomarkers (ie, urinary kidney injury molecule-1 levels), and increased mRNA expressions of proinflammatory cytokines (IL-1ß, IL-12p40, and IL-18) and chemokines (intercellular adhesion molecule-1 and CCL2/monocyte chemoattractant protein-1). The mRNA expression of FasL in the kidney was increased in the IL-18Rα-deficient mice compared to the WT mice. The adoptive transfer of splenocytes by WT mice led to decreased renal IRI compared to the IL-18Rα-deficient mice. In vitro, the mRNA expression of FasL on TECs was promoted in the presence of recombinant IL-18. These data reveal that IL-18Rα has an anti-inflammatory effect in IRI-induced AKI. Above all, IL-18 enhanced the inflammatory mechanisms and the apoptosis of TECs through the Fas/FasL pathway by blocking IL-18Rα.

Endogenous Tim-1 promotes severe systemic autoimmunity and renal disease MRL-Fas(lpr) mice.

The T-cell immunoglobulin mucin 1, also known as kidney injury molecule-1, modulates CD4+ T-cell responses and is also expressed by damaged proximal tubules within the kidney. Both Th subset imbalance (Th1/Th2/Th17) and regulatory T-cell and B-cell alterations contribute to the pathogenesis of autoimmune disease. This study investigated the effects of an inhibitory anti-T-cell immunoglobulin mucin 1 antibody (RMT1-10) in lupus-prone MRL-Fas(lpr) mice. MRL-Fas(lpr) mice were treated with RMT1-10 or a control antibody intraperitoneally twice weekly from 3 mo of age for 16 wk. RMT1-10 treatment significantly improved survival, limited the development of lymphadenopathy and skin lesions, preserved renal function and decreased proteinuria, reduced serum anti-DNA antibody levels, and attenuated renal leukocyte accumulation. Th1 and Th17 cellular responses systemically and intrarenally were reduced, but regulatory T and B cells were increased. RMT1-10 treatment also reduced glomerular immunoglobulin and C3 deposition and suppressed cellular proliferation and apoptosis. Urinary excretion and renal expression of kidney injury molecule-1 was reduced, reflecting diminished interstitial injury. As RMT1-10 attenuated established lupus nephritis, manipulating immune system T-cell immunoglobulin mucin 1 may represent a therapeutic strategy in autoimmune diseases affecting the kidney.

Dynamic photodamage of red blood cell induced by CisDiMPyP porphyrin.

It is well-known that oxidative damage in red blood cell (RBC) usually causes morphological changes and increased membrane rigidity. Although many studies have focused on investigating how RBC responds to a photodynamic stimulus, the intermediate steps between membrane damage and hemolysis are not reported. To give a comprehensive insight into changes of RBC membrane property under different oxidative damage levels, we employed the photoactivation of CisDiMPyP porphyrin that primarily generates singlet oxygen 1O2 as oxidant species. We found that there were distinguishable characteristic damages depending on the 1O2 flux over the membrane, in a way that each impact of photooxidative damage was categorized under three damage levels: mild (maintaining the membrane morphology and elasticity), moderate (membrane elongation and increased membrane elasticity) and severe (wrinkle-like deformation and hemolysis). When sodium azide (NaN3) was used as a singlet oxygen quencher, delayed cell membrane alterations and hemolysis were detected. The delay times showed that 1O2 indeed plays a key role that causes RBC photooxidation by CisDiMPyP. We suggest that the sequence of morphological changes (RBC discoid area expansion, wrinkle-like patterns, and hemolysis) under photooxidative damage occurs due to damage to the lipid membrane and cytoskeletal network proteins.

Blockade of IL-18Rα-mediated signaling pathway exacerbates neutrophil infiltration in imiquimod-induced psoriasis murine model.

Psoriasis is an immune-mediated inflammatory disease of the skin, which is characterized by epidermal hyperkeratosis and neutrophil infiltration. The interleukin (IL)-17/IL-23 pathway and associated cytokines play major roles in the pathogenesis and exacerbation of psoriasis. The IL-18/IL-18 receptor (R) α signaling pathway is important for Th1 cytokine production and differentiation of Th1 cells; however, its role in the pathogenesis of psoriasis remains unknown. In this study, we investigated the effect of the IL-18Rα-mediated signaling pathway in the pathogenesis of psoriasis in Il18ra-deficient mice (Il18ra-/-) and wild-type imiquimod (IMQ)-induced psoriatic dermatitis model mice. Blocking this pathway exacerbated IMQ-induced psoriatic skin inflammation. Il18ra deficiency led to significant increases in the levels of IL-1ß, IL-6, IL-8, IL-17A, IL-23, and chemokine (C-X-C motif) ligand 2 in skin lesions. Gr1-positive cells highly infiltrated psoriatic skin lesions in Il18ra-/- mice compared to those in wild-type mice. Citrullinated histone H3-positive area was relatively broad in Il18ra-/- mice. These results suggest that IL-18Rα-mediated signaling pathways may inhibit psoriatic skin inflammation by regulating infiltration and activation of neutrophil and other innate immune cells.

A mathematical model of fibrinogen-mediated erythrocyte-erythrocyte adhesion.

Erythrocytes are deformable cells that undergo progressive biophysical and biochemical changes affecting the normal blood flow. Fibrinogen, one of the most abundant plasma proteins, is a primary determinant for changes in haemorheological properties, and a major independent risk factor for cardiovascular diseases. In this study, the adhesion between human erythrocytes is measured by atomic force microscopy (AFM) and its effect observed by micropipette aspiration technique, in the absence and presence of fibrinogen. These experimental data are then used in the development of a mathematical model to examine the biomedical relevant interaction between two erythrocytes. Our designed mathematical model is able to explore the erythrocyte-erythrocyte adhesion forces and changes in erythrocyte morphology. AFM erythrocyte-erythrocyte adhesion data show that the work and detachment force necessary to overcome the adhesion between two erythrocytes increase in the presence of fibrinogen. The changes in erythrocyte morphology, the strong cell-cell adhesion and the slow separation of the two cells are successfully followed in the mathematical simulation. Erythrocyte-erythrocyte adhesion forces and energies are quantified and matched with experimental data. The changes observed on erythrocyte-erythrocyte interactions may give important insights about the pathophysiological relevance of fibrinogen and erythrocyte aggregation in hindering microcirculatory blood flow.

The Impact of Early Optimization of Infliximab Blood Concentrations >1 µg/mL on Therapeutic Effectiveness in Rheumatoid Arthritis.

BACKGROUND: Infliximab is a human-murine chimeric monoclonal IgG antibody against tumor necrosis factor that is used in combination with methotrexate for the treatment of moderate to severe rheumatoid arthritis (RA). The trough concentration of serum infliximab required to control disease activity in RA is ≥1 µg/mL, and we investigated whether this trough concentration can predict the effectiveness of RA treatment. METHODS: We retrospectively analyzed the cases of 76 patients with RA. The REMICHECK Q® (REMIQ) is a kit that can check for serum infliximab concentrations. Infliximab concentrations >1 µg/mL at 14 weeks after an initial infliximab induction is considered REMIQ-positive, otherwise considered REMIQ-negative. Here, we determined the retention rates and investigated the clinical and serologic features of REMIQ-positive and REMIQ-negative patients. RESULTS: At 14 weeks, significantly more of the REMIQ-positive patients (n = 46) were responders compared to the non-responders (n = 30). The retention rate at 54 weeks was also significantly higher in the REMIQ-positive group versus the negative group. After 14 weeks, more patients in the REMIQ-negative group were considered inadequate responders, and their infliximab doses were escalated. At baseline, the REMIQ-positive group had significantly lower C-reactive protein (CRP) levels compared to the negative group. Cox regression analysis with multiple variables showed that the positivity of REMIQ (hazard ratio [HR] 2.10 and 95% confidence interval [CI]: 1.55-5.71) at baseline was associated with the achievement of low disease activity. The positivities of rheumatoid factor and anti-CCP antibody at baseline were associated with the achievement of remission with infliximab treatment (HR 0.44, 95% CI: 0.09-0.82 and HR 0.35, 95% CI: 0.04-0.48, respectively). CONCLUSIONS: The results of this study suggest that the control of RA disease activity may be facilitated by using the REMIQ kit at 14 weeks to check whether it is necessary to increase a patient's infliximab dose to ensure a therapeutic blood concentration that will help the patient achieve low disease activity.

Signaling through the interleukin-18 receptor α attenuates inflammation in cisplatin-induced acute kidney injury.

Interleukin (IL)-18 is produced by leukocytes and renal parenchymal cells (tubular epithelial cells, podocytes, and mesangial cells). The IL-18 receptor (IL-18R) is expressed on these cells in cisplatin-induced acute kidney injury, but the role of IL-18R is unknown. To help define this, we compared IL-18Rα knockout with wild-type mice in cisplatin-induced acute kidney injury and found deteriorated kidney function, tubular damage, increased accumulation of leukocytes (CD4(+) and CD8(+) T-cells, macrophages, and neutrophils), upregulation of early kidney injury biomarkers (serum TNF, urinary IL-18, and KIM-1 levels), and increased expression of pro-inflammatory molecules downstream of IL-18. In vitro, leukocytes from the spleen and kidneys of the knockout mice produced greater amounts of pro-inflammatory cytokines upon stimulation with concanavalin A compared to that in wild-type mice. Levels of the suppressor of cytokine signaling 1 and 3 (negative regulators of cytokine signaling) were reduced in the spleen and kidneys of IL-18Rα-deficient compared to wild-type mice. Adoptive transfer of wild-type splenocytes by IL-18Rα-deficient mice led to decreased cisplatin nephrotoxicity compared to control IL-18Rα-deficient mice. In contrast, anti-IL-18Rα and anti-IL-18Rß antibody treatment tended to increase cisplatin nephrotoxicity in wild-type mice. Thus, signaling through IL-18Rα activates both inflammation-suppressing and pro-injury pathways in cisplatin-induced acute kidney injury.