CANE, a Component of the NLRP3 Inflammasome, Promotes Inflammasome Activation.

The nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3, also called cryopyrin) inflammasome is an intracellular innate immune complex, which consists of the pattern-recognition receptor NLRP3, the adaptor apoptosis-assciated speck-like protein containing a caspase recruitment domain, and procaspase-1. Aberrant activation of the NLRP3 inflammasome causes an autoinflammatory disease called cryopyrin-associated periodic syndrome (CAPS). CAPS is caused by gain-of-function mutations in the NLRP3-encoding gene CIAS1; however, the mechanism of CAPS pathogenesis has not been fully understood. Thus, unknown regulators of the NLRP3 inflammasome, which are associated with CAPS development, are being investigated. To identify novel components of the NLRP3 inflammasome, we performed a high-throughput screen using a human protein array, with NLRP3 as the bait. We identified a NLRP3-binding protein, which we called the cryopyrin-associated nano enhancer (CANE). We demonstrated that CANE increased IL-1ß secretion after NLRP3 inflammasome reconstitution in human embryonic kidney 293T cells and formed a "speck" in the cytosol, a hallmark of NLRP3 inflammasome activity. Reduced expression of endogenous CANE decreased IL-1ß secretion upon stimulation with the NLRP3 agonist nigericin. To investigate the role of CANE in vivo, we developed CANE-transgenic mice. The PBMCs and bone marrow-derived macrophages of CANE-transgenic mice exhibited increased IL-1ß secretion. Moreover, increased autoinflammatory neutrophil infiltration was observed in the s.c. tissue of CANE-transgenic versus wild-type mice; these phenotypes were consistent with those of CAPS model mice. These findings suggest that CANE, a component of the NLRP3 inflammasome, is a potential modulator of the inflammasome and a contributor to CAPS pathogenesis.

Unveiling the Genomic Landscape of Intraductal Carcinoma of the Prostate Using Spatial Gene Expression Analysis.

Intraductal carcinoma of the prostate (IDCP) has recently attracted increasing interest owing to its unfavorable prognoses. To effectively identify the IDCP-specific gene expression profile, we took a novel approach of characterizing a typical IDCP case using spatial gene expression analysis. A formalin-fixed, paraffin-embedded sample was subjected to Visium CytAssist Spatial Gene Expression analysis. IDCP within invasive prostate cancer sites was recognized as a distinct cluster separate from other invasive cancer clusters. Highly expressed genes defining the IDCP cluster, such as MUC6, MYO16, NPY, and KLK12, reflected the aggressive nature of high-grade prostate cancer. IDCP sites also showed increased hypoxia markers HIF1A, BNIP3L, PDK1, and POGLUT1; decreased fibroblast markers COL1A2, DCN, and LUM; and decreased immune cell markers CCR5 and FCGR3A. Overall, these findings indicate that the hypoxic tumor microenvironment and reduced recruitment of fibroblasts and immune cells, which reflect morphological features of IDCP, may influence the aggressiveness of high-grade prostate cancer.

Usefulness of intraoperative rapid immunohistochemistry in the surgical treatment of brain tumors.

In the treatment of primary central nervous system lymphoma (PCNSL), intraoperative rapid pathological diagnosis can dramatically change the surgical strategy, and more accurate diagnostic methods are required. In April 2020, we adopted intraoperative rapid immunohistochemistry (IHC) in addition to conventional rapid intraoperative diagnosis based on morphological assessment, mainly for patients with PCNSL. Here, we investigate the usefulness and significance of intraoperative rapid IHC based on our initial experience. We performed intraoperative rapid IHC using antibodies for cluster of differentiation (CD)20, CD3, leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) using enzyme-labeled antibody methods in 25 patients, including PCNSL patients, from April 2020 to July 2022. We examined the utility of this approach in determining treatment strategies for brain tumors. Postoperative final pathological diagnoses from paraffin-embedded sections were as follows: diffuse large B-cell lymphoma, 16 cases; glioblastoma, six cases; pilocytic astrocytoma, one case; adenocarcinoma, one case; and inflammatory disorder, one case. The entire process took 32 min and staining for CD20, CD3, LCA, and GFAP was comparable to that using paraffin-embedded sections. In all cases, the results of intraoperative rapid IHC were consistent with final pathological diagnoses from paraffin-embedded sections. In addition, in two cases, the results of conventional intraoperative rapid pathological diagnosis based on morphological assessments using frozen sections were drastically changed by adding intraoperative rapid IHC. Intraoperative rapid IHC contributes to deciding appropriate treatment strategies and facilitating early initiation of chemotherapy for PCNSL. This may allow new therapeutic strategies not only for PCNSL but also for other brain tumors.

Spatial Gene Expression Analysis Reveals Characteristic Gene Expression Patterns of De Novo Neuroendocrine Prostate Cancer Coexisting with Androgen Receptor Pathway Prostate Cancer.

Neuroendocrine prostate carcinoma (NEPC) accounts for less than 1% of prostate neoplasms and has extremely poorer prognosis than the typical androgen receptor pathway-positive adenocarcinoma of the prostate (ARPC). However, very few cases in which de novo NEPC and APRC are diagnosed simultaneously in the same tissue have been reported. We report herein a 78-year-old man of de novo metastatic NEPC coexisting with ARPC treated at Ehime University Hospital. Visium CytAssist Spatial Gene Expression analysis (10× genetics) was performed using formalin-fixed, paraffin-embedded (FFPE) samples. The neuroendocrine signatures were upregulated in NEPC sites, and androgen receptor signatures were upregulated in ARPC sites. TP53, RB1, or PTEN and upregulation of the homologous recombination repair genes at NEPC sites were not downregulated. Urothelial carcinoma markers were not elevated. Meanwhile, Rbfox3 and SFRTM2 levels were downregulated while the levels of the fibrosis markers HGF, HMOX1, ELN, and GREM1 were upregulated in the tumor microenvironment of NEPC. In conclusion, the findings of spatial gene expression analysis in a patient with coexisting ARPC and de novo NEPC are reported. The accumulation of cases and basic data will help with the development of novel treatments for NEPC and improve the prognosis of patients with castration-resistant prostate cancer.

Expert perspectives on pathological findings in vasculitis.

Pathological findings are important in the diagnosis of vasculitis. However, due to the rarity of the disease, standard textbooks usually devote only a few pages to this topic, and this makes it difficult for clinicians not specializing in vasculitis to fully understand the pathological findings in vasculitis. To address the paucity of information, we present representative pathological findings in vasculitis classified in the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012). The CHCC2012 classifies 26 vasculitides into seven categories: (1) large-vessel vasculitis, (2) medium-vessel vasculitis, (3) small-vessel vasculitis, including antineutrophil cytoplasmic antibody-associated vasculitis and immune complex small-vessel vasculitis, (4) variable-vessel vasculitis, (5) single-organ vasculitis, (6) vasculitis associated with systemic disease, and (7) vasculitis associated with probable aetiology. Moreover, representative pathological findings of vasculitis-related diseases and non-inflammatory vasculopathy not mentioned in the CHCC2012 are also presented. This will be useful for clinicians to refer to typical pathological findings of vasculitis in daily practice.

PSMA-positive membranes secreted from prostate cancer cells have potency to transform vascular endothelial cells into an angiogenic state.

BACKGROUND: Prostate-specific membrane antigen (PSMA) is highly expressed in poorly differentiated, metastatic, and castration-resistant prostate cancers. Recently, 68Ga-PSMA positron emission tomography/computed tomography has been successfully developed as an effective diagnostic tool for prostate cancer. However, the pathophysiological functions of PSMA in prostate tumors remain unclear. METHODS: We examined the protein expression of PSMA in tumor endothelial cells in human prostate tumors by immunohistochemistry. Prostate cancer tissues were resected by robotic surgery in 2019 at Ehime University from patients with prostate cancer. In vitro, we prepared conditioned medium (CM) derived from a PSMA-positive human prostate cancer cell line, LNCaP, cultured on collagen I gels. We then examined PSMA expression in human umbilical vascular endothelial cells (HUVECs) cultured with the CM. We assessed angiogenic activities by treatment of HUVECs with LNCaP-derived CM using a tube formation assay that mimics angiogenesis. RESULTS: Immunohistochemistry of PSMA and CD31, a marker of endothelial cells, and PSMA-expressing tumor endothelial cells were observed in 4 of 33 prostate cancer patients (12.1%). We also found that the 10,000g pellet fraction of the LNCaP-derived CM containing PSMA-positive membranes, such as microvesicles transformed HUVECs "PSMA-negative" into "PSMA-positive." Furthermore, treatment of HUVECs with the 10,000g pellet fraction of the LNCaP-derived CM significantly promoted tube formation, mimicking angiogenesis in a PSMA-dependent manner. CONCLUSIONS: Our findings revealed the existence of PSMA-positive tumor endothelial cells in human prostate tumors, which enhances tumor angiogenesis in prostate cancer tissues.

Enhanced Masses on Contrast-Enhanced Breast: Differentiation Using a Combination of Dynamic Contrast-Enhanced MRI and Quantitative Evaluation with Synthetic MRI.

BACKGROUND: The addition of synthetic MRI might improve the diagnostic performance of dynamic contrast-enhanced MRI (DCE-MRI) in patients with breast cancer. PURPOSE: To evaluate the diagnostic value of a combination of DCE-MRI and quantitative evaluation using synthetic MRI for differentiation between benign and malignant breast masses. STUDY TYPE: Retrospective, observational. POPULATION: In all, 121 patients with 131 breast masses who underwent DCE-MRI with additional synthetic MRI were enrolled. FIELD STRENGTH/SEQUENCE: 3.0 Tesla, T1 -weighted DCE-MRI and synthetic MRI acquired by a multiple-dynamic, multiple-echo sequence. ASSESSMENT: All lesions were differentiated as benign or malignant using the following three diagnostic methods: DCE-MRI type based on the Breast Imaging-Reporting and Data System; synthetic MRI type using quantitative evaluation values calculated by synthetic MRI; and a combination of the DCE-MRI + Synthetic MRI types. The diagnostic performance of the three methods were compared. STATISTICAL TESTS: Univariate (Mann-Whitney U-test) and multivariate (binomial logistic regression) analyses were performed, followed by receiver-operating characteristic curve (AUC) analysis. RESULTS: Univariate and multivariate analyses showed that the mean T1 relaxation time in a breast mass obtained by synthetic MRI prior to injection of contrast agent (pre-T1 ) was the only significant quantitative value acquired by synthetic MRI that could independently differentiate between malignant and benign breast masses. The AUC for all enrolled breast masses assessed by DCE-MRI + Synthetic MRI type (0.83) was significantly greater than that for the DCE-MRI type (0.70, P < 0.05) or synthetic MRI type (0.73, P < 0.05). The AUC for category 4 masses assessed by the DCE-MRI + Synthetic MRI type was significantly greater than that for those assessed by the DCE-MRI type (0.74 vs. 0.50, P < 0.05). DATA CONCLUSION: A combination of synthetic MRI and DCE-MRI improves the accuracy of diagnosis of benign and malignant breast masses, especially category 4 masses. Level of Evidence 4 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:381-391.

The association between renal elasticity evaluated by Real-time tissue elastography and renal fibrosis.

BACKGROUND: The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the severity of renal fibrosis. Real-time tissue elastography (RTE), which measures heartbeat-induced tissue displacement, can assess the elasticity of organs. Here, we aimed to investigate the correlation between renal elasticity and the extent of fibrosis in renal biopsy samples. METHODS: We investigated 29 consecutive patients who underwent a renal biopsy at Ehime University Hospital from February 2018 to August 2019. Renal fibrosis was categorized into three grades, mild (< 25%), moderate (25-50%), and severe (> 50%), based on the total affected area within the biopsy sample. The association between renal elasticity assessed by RTE and the grade of renal fibrosis was evaluated, and a receiver operating characteristic curve was used to distinguish the severity of renal fibrosis. RESULTS: The mean age and estimated glomerular filtration rate (eGFR) were 58.8 years and 55.2 mL/min/1.73 m2, respectively. The median urine protein-to-creatinine ratio was 1.24 g/gCr. The mean renal elasticity of mild, moderate, and severe renal fibrosis was 3.40, 3.98, and 4.77, respectively. Renal elasticity of native kidneys was significantly positively correlated with the grade of renal fibrosis (ρ = 0.529, P = 0.003). At the cutoff point of 3.81, the area under the curve, sensitivity, and specificity were 0.778, 68.4%, and 81.8%, respectively. CONCLUSION: Real-time tissue elastography is a promising, non-invasive method for assessing renal fibrosis in patients with CKD.

Met-PET uptake index for total tumor resection: identification of 11C-methionine uptake index as a goal for total tumor resection including infiltrating tumor cells in glioblastoma.

Glioblastoma multiforme (GBM) is largely due to glioma stem cells (GSCs) that escape from total resection of gadolinium (Gd)-enhanced tumor on MRI. The aim of this study is to identify the imaging requirements for maximum resection of GBM with infiltrating GSCs. We investigated the relationship of tumor imaging volume between MRI and 11C-methionine (Met)-PET and also the relationship between Met uptake index and tumor activity. In ten patients, tumor-to-contralateral normal brain tissue ratio (TNR) was calculated to evaluate metabolic activity of Met uptake areas which were divided into five subareas by the degrees of TNR. In each GBM, tumor tissue was obtained from subareas showing the positive Met uptake. Immunohistochemistry was performed to examine the tumor proliferative activity and existence of GSCs. In all patients, the volume of Met uptake area at TNR ≦ 1.4 was larger than that of the Gd-enhanced area. The Met uptake area at TNR 1.4 beyond the Gd-enhanced tumor was much wider in high invasiveness-type GBMs than in those of low invasiveness type, and survival was much shorter in the former than the latter types. Immunohistochemistry revealed the existence of GSCs in the area showing Met uptake at TNR 1.4 and no Gd enhancement. Areas at TNR > 1.4 included active tumor cells with relatively high Ki-67 labeling index. In addition, it was demonstrated that GSCs could exist beyond the border of Gd-enhanced tumor. Therefore, to obtain maximum resection of GBMs, including infiltrating GSCs, aggressive surgical excision that includes the Met-positive area at TNR 1.4 should be considered.

Hypoxic Culture Maintains Cell Growth of the Primary Human Valve Interstitial Cells with Stemness.

The characterization of aortic valve interstitial cells (VICs) cultured under optimal conditions is essential for understanding the molecular mechanisms underlying aortic valve stenosis. Here, we propose 2% hypoxia as an optimum VIC culture condition. Leaflets harvested from patients with aortic valve regurgitation were digested using collagenase and VICs were cultured under the 2% hypoxic condition. A significant increase in VIC growth was observed in 2% hypoxia (hypo-VICs), compared to normoxia (normo-VICs). RNA-sequencing revealed that downregulation of oxidative stress-marker genes (such as superoxide dismutase) and upregulation of cell cycle accelerators (such as cyclins) occurred in hypo-VICs. Accumulation of reactive oxygen species was observed in normo-VICs, indicating that low oxygen tension can avoid oxidative stress with cell-cycle arrest. Further mRNA quantifications revealed significant upregulation of several mesenchymal and hematopoietic progenitor markers, including CD34, in hypo-VICs. The stemness of hypo-VICs was confirmed using osteoblast differentiation assays, indicating that hypoxic culture is beneficial for maintaining growth and stemness, as well as for avoiding senescence via oxidative stress. The availability of hypoxic culture was also demonstrated in the molecular screening using proteomics. Therefore, hypoxic culture can be helpful for the identification of therapeutic targets and the evaluation of VIC molecular functions in vitro.

Combined morphological, immunohistochemical and genetic analyses of medulloepithelioma in the posterior cranial fossa.

Medulloepithelioma is a rare and highly malignant primitive neuroectodermal tumor that usually occurs in childhood. The diagnosis of this entity required only morphological analysis until the World Health Organization classification of central nervous system (CNS) tumors was revised, and now genetic analysis is necessary. We report a case of medulloepithelioma in the posterior cranial fossa that was diagnosed by both morphological and genetic analyses based on this classification. A 10-month-old girl was admitted to our hospital with consciousness disturbance and vomiting. Neuroimaging revealed a partially calcified mass and cyst formation in the posterior cranial fossa. Partial resection of the tumor was performed and histological findings revealed multilayered rosettes with LIN28A staining, but genetic analysis showed no amplification of the C19MC microRNA cluster at 19q14.32. Therefore, we diagnosed the tumor as medulloepithelioma belonging to other CNS embryonal tumors. The patient was immediately treated with systemic high-dose chemotherapy. Follow-up neuroimaging 10 months later showed no signs of recurrence. Medulloepitheliomas are difficult to diagnose by routine HE staining and require combined morphological, immunohistochemical and genetic analyses to provide an accurate diagnosis.

Nod2-Nodosome in a Cell-Free System: Implications in Pathogenesis and Drug Discovery for Blau Syndrome and Early-Onset Sarcoidosis.

Nucleotide-binding oligomerization domain-containing protein (Nod) 2 is an intracellular pattern recognition receptor, which recognizes muramyl dipeptide (N-Acetylmuramyl-L-Alanyl-D-Isoglutamine: MDP), a bacterial peptidoglycan component, and makes a NF-κB-activating complex called nodosome with adaptor protein RICK (RIP2/RIPK2). Nod2 mutants are associated with the autoinflammatory diseases, Blau syndrome (BS)/early-onset sarcoidosis (EOS). For drug discovery of BS/EOS, we tried to develop Nod2-nodosome in a cell-free system. FLAG-tagged RICK, biotinylated-Nod2, and BS/EOS-associated Nod2 mutants were synthesized, and proximity signals between FLAG-tagged and biotinylated proteins were detected by amplified luminescent proximity homogeneous assay (ALPHA). Upon incubation with MDP, the ALPHA signal of interaction between Nod2-WT and RICK was increased in a dose-dependent manner. The ALPHA signal of interaction between RICK and the BS/EOS-associated Nod2 mutants was more significantly increased than Nod2-WT. Notably, the ALPHA signal between Nod2-WT and RICK was increased upon incubation with MDP, but not when incubated with the same concentrations, L-alanine, D-isoglutamic acid, or the MDP-D-isoform. Thus, we successfully developed Nod2-nodosome in a cell-free system reflecting its function in vivo, and it can be useful for screening Nod2-nodosome-targeted therapeutic molecules for BS/EOS and granulomatous inflammatory diseases.

Microvasculature of carotid atheromatous plaques: hemorrhagic plaques have dense microvessels with fenestrations to the arterial lumen.

BACKGROUND: Microvessels in atheromatous plaques are well known to play a role in plaque vulnerability associated with intraplaque hemorrhage, but their architecture remains unclear. The morphometry of the microvasculature and hemorrhage of human carotid atheromatous plaques (CAPs) were evaluated, and 3-dimensional (3D) reconstruction of the microvessels was performed. METHODS: CAPs were obtained by endarterectomy in 42 patients. The specimens were analyzed using light microscopy. Plaque hemorrhage was defined as an area-containing red blood cells (>1 mm2). To determine the histopathologic features of plaque hemorrhage, the plaque area was divided into 4 regions: cap, shoulder, lipid/necrotic core, and media. Then, the density of microvessels and macrophages in each region was quantified. Two representative lesions with either hemorrhagic or nonhemorrhagic plaque were cut into 90 serial sections. The sections were double stained with anti-CD34 and anti-α smooth muscle actin antibodies, scanned using a digital microscope, and reconstructed using TRI-SRF2 software. RESULTS: The hemorrhagic plaques showed a higher density of microvessels than nonhemorrhagic plaques in the shoulder, cap, and lipid/necrotic core (P=.03, .009, and .001, respectively), and there was positive correlations between its density and macrophages in each regions (P<.001, .001, and .019, respectively). 3D imaging also revealed dense microvessels with a network structure in the cap and shoulder regions of hemorrhagic plaques, and some of the vessels were fenestrated to the arterial lumen. CONCLUSIONS: The microvasculature of plaques with intraplaque hemorrhage was dense, some of which fenestrated to the arterial lumen. The pathologic 3D imaging revealed precise architecture of microvasculature of plaques.

Reliable intraoperative diagnostic methods for PCNSL: utility of combining intraoperative immunohistochemistry, cytology, and flow cytometry in achieving optimal treatment.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rapidly growing malignant tumor that typically shows sensitivity to high-dose methotrexate-based chemotherapy. Rapid diagnosis and early chemotherapy are thus essential to obtain the best outcome. To accomplish this, we have performed intraoperative rapid immunohistochemistry (IHC) as an examination method for obtaining accurate diagnosis during surgery. Here, to markedly enhance the accuracy of intraoperative rapid IHC, the utility of adding intraoperative rapid examinations of cytology and flow cytometry (FCM) in addition to rapid IHC was investigated. METHODS: From April 2020 to January 2024, we performed intraoperative rapid IHC in 35 patients with intracranial lesions, including PCNSL. In the last 17 of these cases, intraoperative cytology and FCM were also performed simultaneously. We examined the utility of examination methods in determining treatment strategies for brain tumors, particularly early therapeutic intervention for PCNSL. RESULTS: Postoperative final pathological diagnoses from paraffin-embedded sections were as follows: 20 PCNSLs, 9 glioblastomas, 4 diffuse gliomas, 1 meningioma, and 1 inflammatory disorder. In all cases, results from intraoperative rapid IHC were consistent with final pathological diagnoses from paraffin-embedded sections. In two cases, results from conventional intraoperative rapid pathological diagnoses based on morphological assessments using frozen sections changed with the addition of intraoperative rapid IHC. Further, the time from surgery to initiation of chemotherapy for PCNSL was significantly reduced by adding cytology and FCM to rapid IHC alone (only rapid IHC group: 7.3 days, combination group: 1.6 days; p = 0.015). CONCLUSIONS: The combination of rapid intraoperative IHC, cytology, and FCM contributes to deciding appropriate treatment strategies and facilitating early initiation of chemotherapy for PCNSL. These examination methods may allow new therapeutic strategies for not only PCNSL, but also other brain tumors.

Capillary-based enzyme-linked immunosorbent assay for highly sensitive detection of thrombin-cleaved osteopontin in plasma.

In this study, a highly sensitive capillary-based enzyme-linked immunosorbent assay (ELISA) has been developed for the analysis of picomolar levels of thrombin-cleaved osteopontin (trOPN), a potential biomarker for ischemic stroke, in human plasma. Using a square capillary coated with 8.5 µg/ml anti-human trOPN capture antibody for ELISA, the linear range obtained was 2 to 16 pM trOPN antigen. This concentration range was in the detection window of trOPN antigen in plasma samples. Compared with the conventional microplate-based ELISA, the current capillary technique significantly reduced the amounts of reagent from milliliter to microliter, reduced the analysis time from 8 to 3 h, and had a better sensitivity and detection limit performance from approximately 50 pM down to 2 pM of trOPN antigen. These results indicate that this capillary-based immunoassay is a potential tool for biomarker detection and may be useful in clinical trials and medical diagnostic applications.

Intestinal edema induced by LPS-induced endotoxemia is associated with an inflammasome adaptor ASC.

The apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC)/caspase-1/interleukin(IL)-1ß axis, also known as the inflammasome pathway, is indispensable for IL-1ß activation in response to various pathogens or own damages. Previously, we developed an NLRP3-inflammasome using a cell-free system and identified ASC targeting drugs; thus, examination of ASC-related histopathology in various diseases could help to provide indications for these drugs. Here, we generated mice deficient only in ASC-protein (ASC-deficient (AD) mice) using CRISPR/Cas9 technology, studied which tissues were most affected, and obtained histopathological images of lipopolysaccharide (LPS)-induced endotoxemia. C57BL/6 wild-type (WT) and (AD) mice were injected intraperitoneally with a lethal dose (50 µg/g) of LPS. Statistical analysis of the survival of C57BL/6 mice and AD mice was performed using the Kaplan-Meier method and the log-rank test. The histopathological findings of multiple tissues from these mice were compared. Acute inflammation (e.g., catarrhal inflammation), along with congestion was observed in the colon of WT mice but not in that of AD mice. Adhesion of neutrophils to capillaries, along with interstitial infiltration, were observed in multiple tissues from WT mice. In AD mice, neutrophil infiltration was less severe but remained evident in the stomach, small intestine, heart, liver, kidney, spleen, and brain. Notably, there was no difference between WT and AD mice with respect to alveolar neutrophil infiltration and interstitial edema. These findings suggest that even though ASC contributes to systemic inflammation, it is dependent on the tissue involved. Intestinal congestion and edema might be good candidates for anti-ASC-targeted therapy.

What is the Best Preoperative Quantitative Indicator to Differentiate Primary Central Nervous System Lymphoma from Glioblastoma?

BACKGROUND: The role of surgery in primary central nervous system lymphoma (PCNSL) is to allow pathological diagnosis from tumor biopsy. However, PCNSL is often difficult to distinguish from other tumors, particularly glioblastoma multiforme (GBM). Quantitative evaluations to facilitate differentiation between PCNSL and GBM would be useful. Here, we investigated the best examinations for exact differentiation of PCNSL from GBM among preoperative examinations, including imaging studies and tumor markers. METHODS: Various examinations were performed for 68 patients with PCNSL , including serum soluble interleukin 2 receptor, ß2-microglobulin (MG) in cerebrospinal fluid (CSF), diffusion-weighted imaging, 11C-methionine-positron emission tomography (PET), and 18F-fluorodeoxyglucose (FDG)-PET. These results were compared with findings from 28 patients with consecutive GBM who underwent the same examinations to evaluate the utility and accuracy of different investigations. RESULTS: CSF ß2-MG ≥2.0 mg/L was relatively specific for PCNSL, offering 95.0% sensitivity and 85.7% specificity. Tumor-to-contralateral normal brain tissue ratio ≥2.4 on 18F-FDG-PET was also quite specific for PCNSL, offering 83.8% sensitivity and 95.2% specificity. No other examinations displayed any significant differences in quantitative differential markers between PCNSL and GBM. CONCLUSIONS: Both ß2-MG ≥2.0 mg/dL in CSF and tumor-to-contralateral normal brain tissue ratio ≥2.4 from 18F-FDG-PET allow quantitative differentiation of PCNSL from GBM, potentially representing clinically useful indicators. These findings could lead to innovative methods for differentiating PCNSL from GBM as well as new treatment strategies for other brain tumors.

Bioprosthetic Valve Deterioration: Accumulation of Circulating Proteins and Macrophages in the Valve Interstitium.

Histologic evaluations revealed excessive accumulations of macrophages and absence of fibroblastic interstitial cells in explanted bioprosthetic valves. Comprehensive gene and protein expression analysis and histology unveiled an accumulation of fibrinogen and plasminogen, an activator of infiltrated macrophages, from degenerated valve surfaces in the interstitial spaces. These pathologies were completely reproduced in a goat model replaced with an autologous pericardium-derived aortic valve. Further preclinical animal experiments using goats demonstrated that preventing infiltration of macrophages and circulating proteins by increasing collagen density and leaflet strength is an effective treatment option.

LOX-1 deficiency increases ruptured abdominal aortic aneurysm via thinning of adventitial collagen.

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a key mediator of inflammation and plays an important role in the pathogenesis of atherosclerosis. Conversely, LOX-1 deficiency has been shown to decrease inflammation and atherosclerosis, both of which have been proposed to contribute to abdominal aortic aneurysm (AAA) pathogenesis. However, the role of LOX-1 in AAA pathogenesis remains unknown. Here, we investigated the effects of Olr1 (which encodes LOX-1) deletion on angiotensin II (Ang II)-induced AAA in apolipoprotein E knockout (ApoE KO) mice to determine whether LOX-1 deficiency mitigates AAA development. To accomplish this, we used serial, non-invasive ultrasound assessment, which revealed that the incidence and expansion rate of AAA were similar regardless of Olr1 deletion. However, Olr1 deletion significantly increased severe AAAs, including ruptured AAAs resulting in death. Oil Red O staining of the harvested aortas showed that the extent of atheroma burden localized in aneurysmal lesions did not differ between LOX-1-deficient and control mice, suggesting that Olr1 deletion did not decrease atheroma burden in the aneurysmal wall. Further histopathological analysis revealed that aneurysmal lesions in LOX-1-deficient mice had fewer fibroblasts and myofibroblasts, as well as thinner adventitial collagen, although the degree of elastin fragmentation or disruption was similar between LOX-1-deficient and control mice. An in vitro study confirmed that the proliferation of adventitial fibroblasts collected from LOX-1-deficient mice was significantly attenuated despite Ang II stimulation. In conclusion, Olr1 deletion may not mitigate aneurysm development but rather increases the vulnerability of rupture by suppressing adventitial fibroblast proliferation and collagen synthesis.

Inflammasome assembly is required for intracellular formation of ß2-microglobulin amyloid fibrils, leading to IL-1ß secretion.

INTRODUCTION: Dialysis-related amyloidosis (DRA) caused by ß2-microgloblin (B2M) fibrils is a serious complication for patients with kidney failure on long-term dialysis. Deposition of B2M amyloid fibrils is thought to be due not only to serum extracellular B2M but also to infiltrating inflammatory cells, which may have an important role in B2M amyloid deposition in osteoarticular tissues in patients with DRA. Here, we asked whether B2M amyloid fibrils activate the inflammasome and contribute to formation and deposition of amyloid fibrils in cells. METHODS: Amyloid formation was confirmed by a thioflavin T (ThT) spectroscopic assay and scanning electron microscopy (SEM). Activation of inflammasomes was assessed by detecting interleukin (IL)-1ß in culture supernatants from human embryonic kidney (HEK) 293T cells ectopically expressing inflammasome components. IL-1ß secretion was measured by enzyme-linked immunosorbent assay. Expression and co-localization were analyzed by immunohistochemistry and dual immunofluorescence microscopy. RESULTS: B2M amyloid fibrils interacted directly with NLRP3/Pyrin and to activate the NLRP3/Pyrin inflammasomes, resulting in IL-1ß secretion. When HEK293T cells were transfected with inflammasome components NLRP3 or Pyrin, along with ASC, pro-caspase-1, pro-IL-1ß, and B2M, ThT fluorescence intensity increased. This was accompanied by IL-1ß secretion, which increased in line with the amount of transfected B2M. In this case, morphological glowing of amyloid fibrils was observed by SEM. In the absence of ASC, there was no increase in ThT fluorescence intensity or IL-1ß secretion, or any morphological glowing of amyloid fibrils. NLRP3 or Pyrin and B2M were co-localized in a "speck" in HEK293T cells, and co-expressed in infiltrated monocytes/macrophages in the osteoarticular synovial tissues in a patient with DRA. CONCLUSION: Taken together, these data suggest that inflammasome assembly is required for the subsequent triggering of intracellular formation of B2M amyloid fibrils, which may contribute to osteoarticular deposition of B2M amyloid fibrils and inflammation in patients with DRA.