Atrial electrical remodeling and function after transcatheter aortic valve replacement in patients with aortic stenosis.

To examine reverse atrial electrical remodeling in patients with aortic stenosis (AS) after trans-catheter aortic valve replacement (TAVR). In 65 consecutive patients with severe AS (83 ± 4 years, 47 (72.3%) females), we analyzed ECG records for the P wave duration (PWD) in lead II and P-terminal force (PTFV1) in V1, and measured cardiac dimensions and function by echocardiography (ECHO) following TAVR. Biomarkers were measured to assess myocardial injury by TAVR. TAVR was successfully performed without major complications: the aortic valve area increased from 0.62 ± 0.14 cm2 to 1.52 ± 0.24cm2, and the trans-aortic pressure gradient decreased from 58.4 ± 15.9 mmHg to 15.0 ± 19.6 mmHg. PWD and PTFV increased immediately after TAVR and returned to the pre-TAVR levels on the next day. Then, the PWD declined toward 6 months after TAVR non-significantly in all patients, but significantly in 25 patients with baseline PWD ≥ 130 ms (P = 0.039). PTFV1 showed no long-term change. Improvement was observed in the ejection fraction, all thickness of the left ventricle and in the left atrial dimensions on ECHO. After recovery from transient aggravation by TAVR procedure, PWD reversed slowly, and the change was significant in those with baseline PWD ≥ 130 ms while change in PTFV1 was not significant at 6 months of follow-up. ECHO showed a reversal of remodeling in the left ventricle and in the left atrial dimension after TAVR.

A novel complement inhibitor sMAP-FH targeting both the lectin and alternative complement pathways.

Inhibition of the complement activation has emerged as an option for treatment of a range of diseases. Activation of the lectin and alternative pathways (LP and AP, respectively) contribute to the deterioration of conditions in certain diseases such as ischemia-reperfusion injuries and age-related macular degeneration (AMD). In the current study, we generated dual complement inhibitors of the pathways MAp44-FH and sMAP-FH by fusing full-length MAp44 or small mannose-binding lectin-associated protein (sMAP), LP regulators, with the N-terminal five short consensus repeat (SCR) domains of complement factor H (SCR1/5-FH), an AP regulator. The murine forms of both fusion proteins formed a complex with endogenous mannose-binding lectin (MBL) or ficolin A in the circulation when administered in mice intraperitoneally. Multiple complement activation assays revealed that sMAP-FH had significantly higher inhibitory effects on activation of the LP and AP in vivo as well as in vitro compared to MAp44-FH. Human form of sMAP-FH also showed dual inhibitory effects on LP and AP activation in human sera. Our results indicate that the novel fusion protein sMAP-FH inhibits both the LP and AP activation in mice and in human sera, and could be an effective therapeutic agent for diseases in which both the LP and AP activation are significantly involved.

Laparoscopic distal pancreatectomy for pancreatic arteriovenous malformation complicated with portal hypertension.

Pancreatic arteriovenous malformation (PAVM) is defined as a vascular anomaly with an abnormal anastomosis of the arterial and portal networks within the pancreas. Treatment modalities of PAVM include transarterial embolisation (TAE), irradiation and operation. Most patients treated with TAE alone will experience recurrence, so surgery is the best radical treatment. A female patient was admitted to our institution for the treatment of haematemesis. Examination revealed varices in the oesophagus and stomach, collateral circulation development caused by portal hypertension and PAVM of the pancreas. Surgical treatment was intended to reduce left portal hypertension. In this case, collateral circulation were considered dangerous points for unexpected bleeding. TAE was performed on the splenic artery before surgery to reduce blood flow in the areas with collateral circulation. En bloc resection of retroperitoneal tissue using the surgical procedure of radical antegrade modular pancreatosplenectomy was effective to minimise blood loss.

Utility of Saline-Induced Resting Full-Cycle Ratio Compared with Resting Full-Cycle Ratio and Fractional Flow Reserve.

BACKGROUND: The saline-induced distal coronary pressure/aortic pressure ratio predicted fractional flow reserve (FFR). The resting full-cycle ratio (RFR) represents the maximal relative pressure difference in a cardiac cycle. Therefore, the present study aimed to compare the results of saline-induced RFR (sRFR) with FFR. METHODS: Seventy consecutive lesions with only moderate stenosis were included. The FFR, RFR, and sRFR values were compared. The sRFR was assessed using an intracoronary bolus infusion of saline (2 mL/s) for five heartbeats. The FFR was obtained after an intravenous injection of papaverine. RESULTS: Overall, the FFR, sRFR, and RFR values were 0.78 ± 0.12, 0.79 ± 0.13, and 0.83 ± 0.14, respectively. With regard to anatomical morphology were 40, 18, and 12 cases of focal, diffuse, and tandem lesion. There was a significant correlation between the sRFR and FFR (R = 0.96, p < 0.01). There were also significant correlations between the sRFR and FFR in the left coronary and right coronary artery (R = 0.95, p < 0.01 and R = 0.98, p < 0.01). Furthermore, significant correlations between sRFR and FFR were observed in not only focal but also in nonfocal lesion including tandem and diffuse lesions (R = 0.93, p < 0.01 and R = 0.97, p < 0.01). A close agreement on FFR and sRFR was shown using the Bland-Altman analysis (95% CI of agreement: -0.08-0.07). In the receiver operating characteristic curve analysis, the cutoff value of sRFR to predict an FFR of 0.80 was 0.81 (area under curve, 0.97; sensitivity 90.6%; and specificity 98.2%). CONCLUSION: The sRFR can accurately and safely predict the FFR and might be effective for diagnosing ischemia.

The effect of the debulking by excimer laser coronary angioplasty on long-term outcome compared with drug-coating balloon: insights from optical frequency domain imaging analysis.

This study evaluated the 1-year efficacy of excimer laser coronary angioplasty (ELCA) before drug-coated balloon (DCB) dilatation for the treatment of in-stent restenosis (ISR). Forty consecutive patients with ISR were treated by DCB with or without the use of ELCA (ELCA plus DCB, N = 20; DCB alone, N = 20). Debulking efficiency (DE) value was defined as the neointima area on optical frequency domain imaging (OFDI) debulked by ELCA. The patients in the ELCA plus DCB group were divided into two groups (greater DE (GDE), N = 10; smaller DE (SDE), N = 10) based on the median value of DE. Thereafter, the ISR segment was prepared with a scoring balloon, followed by DCB. At follow-up, binary restenosis and target lesion revascularization (TLR) were evaluated. There were no significant differences in baseline characteristics such as age, comorbidity, and ISR type. Overall, the incidence of neoatherosclerosis in the ISR segment was 17.5%. Post-PCI, acute gain of minimum lumen diameter on quantitative coronary angiography and of minimum lumen area on OFDI was numerically higher in the GDE than in the SDE and the DCB alone group. At follow-up, the occurrences of binary restenosis and TLR in the ELCA plus DCB group were 20.0% and 10.0%; these values in the DCB alone group were 20.0% and 20.0%, respectively. Two patients from the SDE and none from the GDE developed TLR. DCB alone treatment was inferior to ELCA plus DCB treatment. However, greater ELCA debulking might be required to obtain optimal outcomes.

Deconstructing the Lectin Pathway in the Pathogenesis of Experimental Inflammatory Arthritis: Essential Role of the Lectin Ficolin B and Mannose-Binding Protein-Associated Serine Protease 2.

Complement plays an important role in the pathogenesis of rheumatoid arthritis. Although the alternative pathway (AP) is known to play a key pathogenic role in models of rheumatoid arthritis, the importance of the lectin pathway (LP) pattern recognition molecules such as ficolin (FCN) A, FCN B, and collectin (CL)-11, as well as the activating enzyme mannose-binding lectin-associated serine protease-2 (MASP-2), are less well understood. We show in this article that FCN A-/- and CL-11-/- mice are fully susceptible to collagen Ab-induced arthritis (CAIA). In contrast, FCN B-/- and MASP-2-/-/sMAp-/- mice are substantially protected, with clinical disease activity decreased significantly (p < 0.05) by 47 and 70%, respectively. Histopathology scores, C3, factor D, FCN B deposition, and infiltration of synovial macrophages and neutrophils were similarly decreased in FCN B-/- and MASP-2-/-/sMAp-/- mice. Our data support that FCN B plays an important role in the development of CAIA, likely through ligand recognition in the joint and MASP activation, and that MASP-2 also contributes to the development of CAIA, likely in a C4-independent manner. Decreased AP activity in the sera from FCN B-/- and MASP-2-/-/sMAp-/- mice with arthritis on adherent anti-collagen Abs also support the hypothesis that pathogenic Abs, as well as additional inflammation-related ligands, are recognized by the LP and operate in vivo to activate complement. Finally, we also speculate that the residual disease seen in our studies is driven by the AP and/or the C2/C4 bypass pathway via the direct cleavage of C3 through an LP-dependent mechanism.

The effect of dapagliflozin treatment on epicardial adipose tissue volume.

BACKGROUND: Glycosuria produced by sodium-glucose co-transporter-2 (SGLT-2) inhibitors is associated with weight loss. SGLT-2 inhibitors reportedly might reduce the occurrence of cardiovascular events. Epicardial adipose tissue (EAT) is a pathogenic fat depot that may be associated with coronary atherosclerosis. The present study evaluated the relationship between an SGLT-2 inhibitor (dapagliflozin) and EAT volume. METHODS: In 40 diabetes mellitus patients with coronary artery disease (10 women and 30 men; mean age of all 40 patients was 67.2 ± 5.4 years), EAT volume was compared prospectively between the dapagliflozin treatment group (DG; n = 20) and conventional treatment group (CTG; n = 20) during a 6-month period. EAT was defined as any pixel that had computed tomography attenuation of - 150 to - 30 Hounsfield units within the pericardial sac. Metabolic parameters, including HbA1c, tumor necrotic factor-α (TNF-α), and plasminogen activator inhibitor-1 (PAI-1) levels, were measured at both baseline and 6-months thereafter. RESULTS: There were no significant differences at baseline of EAT volume and HbA1c, PAI-1, and TNF-α levels between the two treatment groups. After a 6-month follow-up, the change in HbA1c levels in the DG decreased significantly from 7.2 to 6.8%, while body weight decreased significantly in the DG compared with the CTG (- 2.9 ± 3.4 vs. 0.2 ± 2.4 kg, p = 0.01). At the 6-month follow-up, serum PAI-1 levels tended to decline in the DG. In addition, the change in the TNF-α level in the DG was significantly greater than that in the CTG (- 0.5 ± 0.7 vs. 0.03 ± 0.3 pg/ml, p = 0.03). Furthermore, EAT volume significantly decreased in the DG at the 6-month follow-up compared with the CTG (- 16.4 ± 8.3 vs. 4.7 ± 8.8 cm3, p = 0.01). Not only the changes in the EAT volume and body weight, but also those in the EAT volume and TNF-α level, showed significantly positive correlation. CONCLUSION: Treatment with dapagliflozin might improve systemic metabolic parameters and decrease the EAT volume in diabetes mellitus patients, possibly contributing to risk reduction in cardiovascular events.

Comparison of clinical outcomes of coronary artery stent implantation in patients with end-stage chronic kidney disease including hemodialysis for three everolimus eluting (EES) stent designs: Bioresorbable polymer-EES, platinum chromium-EES, and cobalt chrome-EES.

BACKGROUNDS: New-generation bioresorbable polymer-everolimus eluting stents (BP-EES) are available. This study aimed to compare the clinical outcomes for BP-EES compared to more established stent designs, namely the platinum chromium-EES (PtCr-EES) and cobalt chrome-EES(CoCr-EES) in patients with the end-stage chronic kidney disease (CKD) including hemodialysis (HD). METHODS: One-hundred-forty-one consecutive stents (BP-EES [n = 44], PtCr-EES [n = 45], and CoCr-EES [n = 52]) were implanted in 104 patients with CKD. All patients underwent a follow-up coronary angiography at 12 months after implantation. End-stage CKD was defined as an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 , or the need for HD. The following outcome variables were compared among the three stent groups after implantation and the 12-month follow-up: target lesion revascularization (TLR), stent thrombosis (ST), and major adverse cardiac event (MACE). Minimal stent diameter (MSD) and %diameter-stenosis (%DS) were measured using quantitative coronary angiography. RESULTS: The overall rate of TLR and MACE was 14.6% and 30.8%, respectively, with no incidence of ST. Immediately after implantation, the MSD (P = 0.22) and %DS (P = 0.42) were equivalent among the three groups. However, at the 12-month follow-up, a tendency towards higher TLR was observed for the BP-EES group (22.7%) compared with the PtCr-EES (8.8%) and CoCr-EES (9.6%) groups (P = 0.07). Late loss in lumen diameter was also significantly greater for the BP-EES (0.51 ± 0.64 mm) group than either the PtCr-EES (0.20 ± 0.61 mm) and CoCr-EES (0.25 ± 0.70 mm) groups (P = 0.03). CONCLUSIONS: BP-EES might increase the risk of in-stent restenosis in patients with end-stage of CKD or the need for HD.

Mannan-Binding Lectin-Associated Serine Protease 1/3 Cleavage of Pro-Factor D into Factor D In Vivo and Attenuation of Collagen Antibody-Induced Arthritis through Their Targeted Inhibition by RNA Interference-Mediated Gene Silencing.

The complement system is proposed to play an important role in the pathogenesis of rheumatoid arthritis (RA). The complement system mannan-binding lectin-associated serine proteases (MASP)-1/3 cleave pro-factor D (proDf; inactive) into Df (active), but it is unknown where this cleavage occurs and whether inhibition of MASP-1/3 is a relevant therapeutic strategy for RA. In the present study, we show that the cleavage of proDf into Df by MASP-1/3 can occur in the circulation and that inhibition of MASP-1/3 by gene silencing is sufficient to ameliorate collagen Ab-induced arthritis in mice. Specifically, to examine the cleavage of proDf into Df, MASP-1/3-producing Df-/- liver tissue (donor) was transplanted under the kidney capsule of MASP-1/3-/- (recipient) mice. Five weeks after the liver transplantation, cleaved Df was present in the circulation of MASP-1/3-/- mice. To determine the individual effects of MASP-1/3 and Df gene silencing on collagen Ab-induced arthritis, mice were injected with scrambled, MASP-1/3-targeted, or Df-targeted small interfering RNAs (siRNAs). The mRNA levels for MASP-1 and -3 decreased in the liver to 62 and 58%, respectively, in mice injected with MASP-1/3 siRNAs, and Df mRNA decreased to 53% in the adipose tissue of mice injected with Df siRNAs; additionally, circulating MASP-1/3 and Df protein levels were decreased. In mice injected with both siRNAs the clinical disease activity, histopathologic injury scores, C3 deposition, and synovial macrophage/neutrophil infiltration were significantly decreased. Thus, MASP-1/3 represent a new therapeutic target for the treatment of RA, likely through both direct effects on the lectin pathway and indirectly through the alternative pathway.

The utility of total lipid core burden index/maximal lipid core burden index ratio within the culprit plaque to predict filter-no reflow: insight from near-infrared spectroscopy with intravascular ultrasound.

Filter-no reflow (FNR) is a phenomenon wherein flow improves after the retrieve of distal protection. Near-infrared spectroscopy with intravascular ultrasound (NIRS-IVUS) enables lipid detection. We evaluated the predictors of FNR during PCI using NIRS-IVUS. Thirty-two patients who underwent PCI using the Filtrap® for acute coronary syndrome (ACS) were enrolled. The culprit plaque (CP) was observed using NIRS-IVUS. Total lipid-core burden index (T-LCBI) and maximal LCBI over any 4-mm segment (max-LCBI4mm) within CP were evaluated. T-LCBI/max-LCBI4mm ratio within CP was calculated as an index of the extent of longitudinal lipid expansion. The attenuation grade (AG) and remodeling index (RI) in CP were analyzed. AG was scored based on the extent of attenuation occupying the number of quadrants. The patients were divided into FNR group (N = 8) and no-FNR group (N = 24). AG was significantly higher in FNR group than in no-FNR group (1.6 ± 0.6 vs. 0.9 ± 0.42, p = 0.01). RI in FNR group tended to be greater than in no-FNR group. T-LCBI/max-LCBI4mm ratio within the culprit plaque was significantly higher in FNR group than in no-FNR group (0.50 ± 0.10 vs. 0.33 ± 0.13, p < 0.01). In multivariate logistic regression analysis, AG > 1.04 (odds ratio [OR] 18.4, 95% confidence interval [CI] 1.5-215.7, p = 0.02) and T-LCBI/max-LCBI4mm ratio > 0.42 (OR 14.4, 95% CI 1.2-176.8, p = 0.03) were independent predictors for the occurrence of FNR. The use of T-LCBI/max-LCBI4mm ratio within CP might be an effective marker to predict FNR during PCI in patients with ACS.

The Comparison of Inappropriate-Low-Doses Use among 4 Direct Oral Anticoagulants in Patients with Atrial Fibrillation: From the Database of a Single-Center Registry.

BACKGROUND: Inappropriate doses of direct oral anticoagulants (DOACs) are often prescribed. This study evaluated the prevalence, outcomes, and predictors of the prescription of inappropriately low doses of 4 types of DOACs in patients with atrial fibrillation (AF). METHODS: We retrospectively analyzed prospectively collected data from a single-center registry with 2272 patients prescribed DOACs for AF (apixaban: 1014; edoxaban: 267; rivaroxaban: 498; dabigatran: 493). Patients were monitored for 2years and classified into appropriate-dose (n = 1,753; including appropriate low doses), inappropriate-low-dose (n = 490) and inappropriate-high-dose groups (n = 29). Major bleeding (MB) and thromboembolic events (TEEs) were evaluated. RESULTS: The mean age was 72 ± 10years. The CHADS2 and HAS-BLED scores were 1.95 ± 1.32 and 1.89 ± .96, respectively. Overall, the incidences of MB and TEE were 2.3 and 2.1 per 100-patinet year, respectively. The inappropriate-low-dose group had younger age, heavier body weight, and higher creatinine clearance value than the appropriate-dose group. Multiple logistic regression analyses demonstrated the following independent determinants of the prescription of an inappropriately low dose: apixaban: HAS-BLED score; edoxaban: age; rivaroxaban: age, creatinine clearance value, HAS-BLED score, CHADS2 score, and antiplatelet therapy; dabigatran: age. There were not significant differences in the incidence of major bleeding and stroke/systemic emboli among the inappropriate-low-dose group of 4 DOACs compared with the appropriate-dose group of 4 DOACs. CONCLUSIONS: In a single-center registry, 23% of patients with AF treated with a DOAC received an inappropriate dose. Several clinical factors, such as age and the creatinine clearance value, can identify patients at risk of under-treatment with DOACs.

Conversion therapy for inoperable advanced gastric cancer patients by docetaxel, cisplatin, and S-1 (DCS) chemotherapy: a multi-institutional retrospective study.

BACKGROUND: Conversion therapy is an option for unresectable metastatic gastric cancer when distant metastases are controlled by chemotherapy; however, the feasibility and efficacy remain unclear. This study aimed to assess the feasibility and efficacy of conversion therapy in patients with initially unresectable gastric cancer treated with docetaxel, cisplatin, and S-1 (DCS) chemotherapy by evaluating clinical outcomes. METHODS: One hundred unresectable metastatic gastric cancer patients, enrolled in three DCS chemotherapy clinical trials, were retrospectively evaluated. The patients received oral S-1 (40 mg/m2 b.i.d.) on days 1-14 and intravenous cisplatin (60 mg/m2) and docetaxel (50-60 mg/m2) on day 8 every 3 weeks. Conversion therapy was defined when the patients could undergo R0 resection post-DCS chemotherapy and were able to tolerate curative surgery. RESULTS: Conversion therapy was achieved in 33/100 patients, with no perioperative mortality. Twenty-eight of the 33 patients (84.8 %) achieved R0 resection, and 78.8 % were defined as histological chemotherapeutic responders. The median overall survival (OS) of patients who underwent conversion therapy was 47.8 months (95 % CI 28.0-88.5 months). Patients who underwent R0 resection had significantly longer OS than those who underwent R1 and R2 resections (P = 0.0002). Of the patients with primarily unresectable metastases, 10 % lived >5 years. Among patients who underwent conversion therapy, multivariate analysis showed that the pathological response was a significant independent predictor for OS. CONCLUSIONS: DCS safely induced a high conversion rate, with very high R0 and pathological response rates, and was associated with a good prognosis; these findings warrant further prospective investigations.

Mannan binding lectin-associated serine protease-2 (MASP-2) critically contributes to post-ischemic brain injury independent of MASP-1.

BACKGROUND: Complement activation via the lectin activation pathway (LP) has been identified as the key mechanism behind post-ischemic tissue inflammation causing ischemia-reperfusion injury (IRI) which can significantly impact the clinical outcome of ischemic disease. This work defines the contributions of each of the three LP-associated enzymes-mannan-binding lectin-associated serine protease (MASP)-1, MASP-2, and MASP-3-to ischemic brain injury in experimental mouse models of stroke. METHODS: Focal cerebral ischemia was induced in wild-type (WT) mice or mice deficient for defined complement components by transient middle cerebral artery occlusion (tMCAO) or three-vessel occlusion (3VO). The inhibitory MASP-2 antibody was administered systemically 7 and 3.5 days before and at reperfusion in WT mice in order to assure an effective MASP-2 inhibition throughout the study. Forty-eight hours after ischemia, neurological deficits and infarct volumes were assessed. C3 deposition and microglia/macrophage morphology were detected by immunohistochemical, immunofluorescence, and confocal analyses. RESULTS: MASP-2-deficient mice (MASP-2(-/-)) and WT mice treated with an antibody that blocks MASP-2 activity had significantly reduced neurological deficits and histopathological damage after transient ischemia and reperfusion compared to WT or control-treated mice. Surprisingly, MASP-1/3(-/-) mice were not protected, while mice deficient in factor B (fB(-/-)) showed reduced neurological deficits compared to WT mice. Consistent with behavioral and histological data, MASP-2(-/-) had attenuated C3 deposition and presented with a significantly higher proportion of ramified, surveying microglia in contrast to the hypertrophic pro-inflammatory microglia/macrophage phenotype seen in the ischemic brain tissue of WT mice. CONCLUSIONS: This work demonstrates the essential role of the low-abundant MASP-2 in the mediation of cerebral ischemia-reperfusion injury and demonstrates that targeting MASP-2 by an inhibitory therapeutic antibody markedly improved the neurological and histopathological outcome after focal cerebral ischemia. These results contribute to identifying the key lectin pathway component driving brain tissue injury following cerebral ischemia and call for a revision of the presently widely accepted view that MASP-1 is an essential activator of the lectin pathway effector component MASP-2.

Contribution of each masticatory muscle to the bite force determined by MRI using a novel metal-free bite force gauge and an index of total muscle activity.

PURPOSE: To develop a metal-free bite force gauge that can monitor the bite force in a strong magnetic field and to analyze the correlations between bite-force and total T2 shift of the mastication muscles. MATERIALS AND METHODS: The gauge used a micro-pressure sensor made of optical fiber. Ten subjects performed a 60-s isometric bite task at 40% of maximum clenching in various occlusal support conditions (intact dentition, right molar loss, or left molar loss). Spin-echo images were taken with a 1.5 Tesla scanner before and immediately after the task to correlate the bite force with the mean voxel count, mean shift in transverse relaxation time (ΔT2), and total T2 shift of each masticatory muscle. RESULTS: Measurements of total T2 shift identified significant correlations between the bite force and activities of the superficial layer of the bilateral masseter muscle, regardless of the occlusion condition (intact dentition: left, P = 0.007 and right, P < 0.001; right molar loss: left, P = 0.02 and right, P = 0.021; and left molar loss: left, P = 0.022 and right, P = 0.049). In contrast, significant correlations were not detected between the bite force and mean ΔT2 (intact dentition: left, P = 0.102 and right, P = 0.053; right molar loss: left, P = 0.393 and right, P = 0.868; and left molar loss: left, P = 0.531 and right, P = 0.92). CONCLUSION: Measurement of total T2 shift using a metal-free bite force gauge is a more sensitive index of individual muscle activity than mean ΔT2 during a bite task. J. MAGN. RESON. IMAGING 2016;44:804-813.

Essential role for the lectin pathway in collagen antibody-induced arthritis revealed through use of adenovirus programming complement inhibitor MAp44 expression.

Previous studies using mannose-binding lectin (MBL) and complement C4-deficient mice have suggested that the lectin pathway (LP) is not required for the development of inflammatory arthritis in the collagen Ab-induced arthritis (CAIA) model. MBL, ficolins and collectin-11 are key LP pattern recognition molecules that associate with three serine proteases-MASP-1, MASP-2, and MASP-3-and with two MBL-associated proteins designated sMAP and MBL-associated protein of 44kDA (MAp44). Recent studies have shown that MAp44, an alternatively spliced product of the MASP-1/3 gene, is a competitive inhibitor of the binding of the recognition molecules to all three MASPs. In these studies, we examined the effect of treatment of mice with adenovirus (Ad) programmed to express human MAp44 (AdhMAp44) on the development of CAIA. AdhMAp44 and Ad programming GFP (AdGFP) expression were injected i.p. in C57BL/6 wild type mice prior to the induction of CAIA. AdhMAp44 significantly reduced the clinical disease activity (CDA) score by 81% compared with mice injected with AdGFP. Similarly, histopathologic injury scores for inflammation, pannus, cartilage and bone damage, as well as C3 deposition in the cartilage and synovium, were significantly reduced by AdhMAp44 pretreatment. Mice treated with AdmMAp44, programming expression of mouse MAp44, also showed significantly decreased CDA score and histopathologic injury scores. In addition, administration of AdhMAp44 significantly diminished the severity of Ross River virus-induced arthritis, an LP-dependent model. Our study provides conclusive evidence that an intact complement LP is essential to initiate CAIA, and that MAp44 may be an appropriate treatment for inflammatory arthritis.

Roles of adipocytes and fibroblasts in activation of the alternative pathway of complement in inflammatory arthritis in mice.

The complement system is involved in mediation of joint damage in rheumatoid arthritis, with evidence suggesting activation of both the classical and alternative pathway (AP). The AP is both necessary and sufficient to mediate collagen Ab-induced arthritis, an experimental animal model of immune complex-induced joint disease. The AP in mice is dependent on MASP-1/3 cleavage of pro-factor D (pro-FD) into mature factor D (FD). The objectives of the current study were to determine the cells synthesizing MASP-1/3 and pro-FD in synovial tissue. Collagen Ab-induced arthritis was studied in wild-type C57BL/6 mice, and the localization of mRNA and protein for FD and MASP-1/3 in synovial adipose tissue (SAT) and fibroblast-like synoviocytes (FLS) was determined using various techniques, including laser capture microdissection. SAT was the sole source of mRNA for pro-FD. Cultured differentiated 3T3 adipocytes, a surrogate for SAT, produced pro-FD but no mature FD. FLS were the main source of MASP-1/3 mRNA and protein. Using cartilage microparticles (CMPs) coated with anti-collagen mAb and serum from MASP-1/3(-/-) mice as a source of factor B, pro-FD in 3T3 supernatants was cleaved into mature FD by MASP-1/3 in FLS supernatants. The mature FD was eluted from the CMP, and was not present in the supernatants from the incubation with CMP, indicating that cleavage of pro-FD into mature FD by MASP-1 occurred on the CMP. These results demonstrate that pathogenic activation of the AP can occur in the joint through immune complexes adherent to cartilage and the local production of necessary AP proteins by adipocytes and FLS.

Mannose-binding lectin-associated serine protease-1 is a significant contributor to coagulation in a murine model of occlusive thrombosis.

Bleeding disorders and thrombotic complications constitute a major cause of death and disability worldwide. Although it is known that the complement and coagulation systems interact, no studies have investigated the specific role or mechanisms of lectin-mediated coagulation in vivo. FeCl(3) treatment resulted in intra-arterial occlusive thrombogenesis within 10 min in wild-type (WT) and C2/factor B-null mice. In contrast, mannose-binding lectin (MBL)-null and MBL-associated serine protease (MASP)-1/-3 knockout (KO) mice had significantly decreased FeCl(3)-induced thrombogenesis. Reconstitution with recombinant human (rh) MBL restored FeCl(3)-induced thrombogenesis in MBL-null mice to levels comparable to WT mice, suggesting a significant role of the MBL/MASP complex for in vivo coagulation. Additionally, whole blood aggregation demonstrated increased MBL/MASP complex-dependent platelet aggregation. In vitro, MBL/MASP complexes were captured on mannan-coated plates, and cleavage of a chromogenic thrombin substrate (S2238) was measured. We observed no significant differences in S2238 cleavage between WT, C2/factor B-null, MBL-A(-/-), or MBL-C(-/-) sera; however, MBL-null or MASP-1/-3 KO mouse sera demonstrated significantly decreased S2238 cleavage. rhMBL alone failed to cleave S2238, but cleavage was restored when rMASP-1 was added to either MASP-1/-3 KO sera or rhMBL. Taken together, these findings indicate that MBL/MASP complexes, and specifically MASP-1, play a key role in thrombus formation in vitro and in vivo.

Mice deficient in ficolin, a lectin complement pathway recognition molecule, are susceptible to Streptococcus pneumoniae infection.

Mannose-binding lectin (MBL) and ficolin are complexed with MBL-associated serine proteases, key enzymes of complement activation via the lectin pathway, and act as soluble pattern recognition molecules in the innate immune system. Although numerous reports have revealed the importance of MBL in infectious diseases and autoimmune disorders, the role of ficolin is still unclear. To define the specific role of ficolin in vivo, we generated model mice deficient in ficolins. The ficolin A (FcnA)-deficient (Fcna(-/-)) and FcnA/ficolin B double-deficient (Fcna(-/-)b(-/-)) mice lacked FcnA-mediated complement activation in the sera, because of the absence of complexes comprising FcnA and MBL-associated serine proteases. When the host defense was evaluated by transnasal infection with a Streptococcus pneumoniae strain, which was recognized by ficolins, but not by MBLs, the survival rate was significantly reduced in all three ficolin-deficient (Fcna(-/-), Fcnb(-/-), and Fcna(-/-)b(-/-)) mice compared with wild-type mice. Reconstitution of the FcnA-mediated lectin pathway in vivo improved survival rate in Fcna(-/-) but not in Fcna(-/-)b(-/-) mice, suggesting that both FcnA and ficolin B are essential in defense against S. pneumoniae. These results suggest that ficolins play a crucial role in innate immunity against pneumococcal infection through the lectin complement pathway.

Targeting of mannan-binding lectin-associated serine protease-2 confers protection from myocardial and gastrointestinal ischemia/reperfusion injury.

Complement research experienced a renaissance with the discovery of a third activation route, the lectin pathway. We developed a unique model of total lectin pathway deficiency, a mouse strain lacking mannan-binding lectin-associated serine protease-2 (MASP-2), and analyzed the role of MASP-2 in two models of postischemic reperfusion injury (IRI). In a model of transient myocardial IRI, MASP-2-deficient mice had significantly smaller infarct volumes than their wild-type littermates. Mice deficient in the downstream complement component C4 were not protected, suggesting the existence of a previously undescribed lectin pathway-dependent C4-bypass. Lectin pathway-mediated activation of C3 in the absence of C4 was demonstrated in vitro and shown to require MASP-2, C2, and MASP-1/3. MASP-2 deficiency also protects mice from gastrointestinal IRI, as do mAb-based inhibitors of MASP-2. The therapeutic effects of MASP-2 inhibition in this experimental model suggest the utility of anti-MASP-2 antibody therapy in reperfusion injury and other lectin pathway-mediated disorders.

Clinical Significance of Adjuvant Surgical Resection for Initially Unresectable Pancreatic Cancer Responsive to Arterial Infusion Chemotherapy.

BACKGROUND/AIMS: We have reported a clinically meaningful local-control effect and a hepatic metastatic tumor-regression effect of transcatheter peripancreatic arterial embolization-hepatic and splenic arterial infusion chemotherapy (TPPAE-HSAIC) for unresectable advanced pancreatic cancer. The aim of this study was to evaluate the clinical significance, of adjuvant surgical resection after TPPAE-HSAIC. METHODOLOGY: We assessed histopathological findings and outcomes of 6 patients who underwent surgical resection of tumors judged to be radically resectable after attaining tumor down-staging or long-term tumor control following TPPAE-HSAIC for pancreatic cancer initially diagnosed as unresectable. RESULTS: Clinical stage at the initial diagnosis was T4N0M0 Stage III in 4 patients and T4N0M1 Stage IV in 2 patients. The durations of TPPAE-HSAIC ranged from 5 to 46 months with a median of 19 months. An R0 resection was performed in 5 of the 6 patients (83%) and pathological down-staging, from the viewpoint of clinical stage, was observed in 4 patients. Of the 5 patients with R0 resection, one died from a postoperative complication at 7 months and another from pulmonary metastasis at 30 months post-operatively, while the other 3 patients have survived for 45 to 83 months to date. CONCLUSIONS: If surgical resection of pancreatic cancer initially diagnosed as unresectable can be carried out in patients responding favorably to TPPAE-HSAIC, the likelihood of long-term survival might be increased.