Histological Evidence Of Inflammation Research Articles

Elevation of serum carcinoembryonic antigen as a possible predictor of response to pulse methylprednisolone in acquired idiopathic generalized anhidrosis.

Acquired idiopathic generalized anhidrosis (AIGA) is a rare disorder primarily observed in Asian populations, particularly in Japan. Although pulse methylprednisolone therapy is an effective treatment for AIGA, predictors of therapeutic response remain poorly defined. To identify factors that predict the efficacy of pulse methylprednisolone therapy in patients with AIGA. Data obtained from 32 patients with AIGA were assessed based on clinical, histopathological and serological examinations. Statistical analyses were conducted to explore predictors of response to pulse methylprednisolone therapy. The average age of participants was 32.1 years (SD 12.3); 66% were male and 34% female. The response to pulse methylprednisolone therapy was closely associated with the time from the onset to start of therapy (Wilcoxson's rank sum test, P = 0.02, n = 27), with earlier intervention resulting in a better outcome. Notably, male patients and patients presenting with severe symptoms at diagnosis responded better to treatment. High serum carcinoembryonic antigen (CEA) levels and histological evidence of inflammation around sweat glands also correlated with a positive therapeutic response. Earlier intervention, elevated serum CEA levels and inflammation around sweat glands are potential indicators of a successful response to pulse methylprednisolone therapy in patients with AIGA.

DOP35 Spatial transcriptomics reveals cellular niches associated with histological inflammation in postoperative Crohn’s Disease

Abstract Background Postoperative Crohn’s disease (CD) recurs in ~70% of patients ≤1 year following ileocolonic resection (ICR), as observed endoscopically. Current understanding of molecular determinants underlying histological intestinal inflammation in patients with postoperative CD recurrence is minimal. To address this issue, we used advanced spatial transcriptomic analyses on intestinal biopsy samples with matched histological and endoscopic assessments from neoterminal ileum, anastomosis, and colon of patients with CD who had undergone colonoscopy following ICR. Methods Formalin-fixed paraffin-embedded (FFPE) tissue biopsies from neoterminal ileum, anastomosis, and colon were prospectively collected from a 15-patient cross-sectional cohort with CD who underwent routine endoscopic assessment following ICR. Spatial transcriptomics was performed on samples using 10X Genomics Visium CytAssist Spatial Gene Expression for FFPE V2.0. Annotation of tissue regions of histologically active inflammation and classification of histologically inactive (Robarts Histopathology Index ≤3 with subscores of 0 for neutrophils in the lamina propria and epithelium) or active disease were performed by an expert gastrointestinal pathologist. R programming language was used for data analysis (Figure). Results Fourteen of the 43 (32.6%) FFPE biopsies had histological evidence of inflammation. Spatial transcriptomics clustering revealed a distinct transcriptional signature by the segregation of 4 clusters ("inflamed clusters") composed mostly (≥69%) of cells from samples defined by histologically active disease. Tissue regions identified as inflamed by expert pathologist annotation contributed to >46% of inflamed clusters’ composition and <15% of remaining clusters. Cell type decomposition and cellular niche analysis revealed immune (e.g., myeloid, T cells, and B cells) and epithelial cells in close proximity sharing a similar microenvironment in 3 inflamed clusters while the 4th cluster was composed of >90% epithelial cells. Differentially expressed genes from the inflamed clusters were similarly expressed across intestinal segments including inflamed anastomotic biopsies and were enriched for signalling pathways involving immune cells recruitment/activation, inflammatory signalling, extracellular matrix organisation, and oxidative stress response. Conclusion This is the first study to explore spatial transcriptomic signatures associated with histological inflammation in patients with postoperative CD recurrence. Our analysis revealed a spatial signature of cellular niches and signalling pathways arising upon histological inflammation, providing insight into therapeutic targets and biomarkers across anatomic locations and the anastomosis.

Depletion of gut microbiota facilitates fibroblast growth factor 21-mediated protection against acute pancreatitis in diabetic mice.

Fibroblast growth factor 21 (FGF21), primarily secreted by the pancreas, liver, and adipose tissues, plays a pivotal role in regulating glucose and lipid metabolism. Acute pancreatitis (AP) is a common inflammatory disease with specific clinical manifestations. Many patients with diabetes present with concurrent inflammatory symptoms. Diabetes exacerbates intestinal permeability and intestinal inflammation, thus leading to the progression to AP. Our previous study indicated that FGF21 significantly attenuated susceptibility to AP in mice. To investigate the potential protective role of FGF21 against AP in diabetic mice. In the present study, a mouse model of AP was established in diabetic (db)/db diabetic mice through ceruletide injections. Thereafter, the protective effects of recombinant FGF21 protein against AP were evaluated, with an emphasis on examining serum amylase (AMS) levels and pancreatic and intestinal inflammatory cytokines [interleukin (IL)-6, tumor necrosis factor-alpha (TNF-), and intestinal IL-1β]. Additionally, the impact of this treatment on the histopathologic changes of the pancreas and small intestinal was examined to elucidate the role of FGF21 in diabetic mice with AP. An antibiotic (Abx) cocktail was administered in combination with FGF21 therapy to investigate whether the effect of FGF21 on AP in diabetic mice with AP was mediated through the modulation of the gut microbiota. Subsequently, the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt), a bioinformatics software package, was used to predict different pathways between the groups and to explore the potential mechanisms by which the gut microbiota influenced the protective effect of FGF21. The results indicated that FGF21 notably diminished the levels of serum AMS (944.5 ± 15.9 vs 1732 ± 83.9, P < 0.01) and inflammatory factors including IL-6 (0.2400 ± 0.55 vs 1.233 ± 0.053, P < 0.01), TNF- (0.7067 ± 0.22 vs 1.433 ± 0.051, P < 0.01), and IL-1β (1.377 ± 0.069 vs 0.3328 ± 0.02542, P < 0.01) in diabetic mice with AP. Moreover, notable signs of recovery were observed in the pancreatic structure of the mice. The histologic evidence of inflammation in the small intestine, including edema and villous damage, was significantly alleviated. FGF21 also significantly altered the composition of the gut microbiota, reestablishing the Bacteroidetes/Firmicutes ratio. Upon treatment with an Abx cocktail to deplete the gut microbiota, the FGF21 + Abx group showed lower levels of serum AMS (0.9328 ± 0.075 vs 0.2249 ± 0.023, P < 0.01) and inflammatory factors (1.083 ± 0.12 vs 0.2799 ± 0.032, p < 0.01) than the FGF21 group. Furthermore, the FGF21 + Abx group exhibited diminished injury to the pancreatic and small intestinal tissues, accompanied by a significant decrease in blood glucose levels (17.50 ± 1.1 vs 9.817 ± 0.69 mmol/L, P < 0.001). These findings underscored the superior protective effects of the combination therapy involving an Abx cocktail with FGF21 over the FGF21 treatment alone in diabetic mice with AP. The gut microbiota composition across different groups was further characterized, and a differential expression analysis of gene functions was undertaken using the PICRUSt2 prediction method. These findings suggested that FGF21 could potentially confer therapeutic effects on diabetic mice with AP by modulating the sulfate reduction I pathway and the superpathway of n-acetylceramide degradation in the gut microbiota. This study reveals the potential of FGF21 in improving pancreatic and intestinal damage recovery, reducing blood glucose levels, and reshaping gut microbiota composition in diabetic mice with AP. Notably, the protective effects of FGF21 are augmented when combined with the Abx cocktail.

Does Timing of Resection Influence the Presence of Inflammation within Congenital Lung Malformations?

Opinion remains divided on whether to resect an asymptomatic congenital lung malformation (CLM) and on optimal timing of resection. This study aimed to determine if age at resection of CLM correlates with the presence of histological inflammation and/or incidence of prior antibiotic administration for lower respiratory tract infection (LRTI). A retrospective review of all CLMs resected between 2009 and 2021 was carried out. Data on antenatal detection, incidence of preoperative antibiotic use for LRTI, operative details, and histological reports were analyzed. Fisher's exact test and logistic regression were used to look for correlation between age at resection and (1) histological inflammation and/or (2) preoperative LRTI. A total of 102 patients underwent resection at age 14 months (interquartile range: 6-23). Eighty percent of children were asymptomatic in the neonatal period and 22% of these went on to develop a respiratory symptom. In total, 59% of specimens had histological evidence of inflammation, with a significantly higher rate of inflammation after 10 months of age (71 vs. 35%; p = 0.0012). Logistic regression showed there was a positive correlation between age at resection and treatment for previous LRTI (p = 0.020). Detection rates of inflammation in specimens resected after 10 months of age are double the rates of those resected prior to 10 months. Delaying resection of CLMs showed a higher frequency of treatment of LRTI. Earlier resection may therefore be advantageous for centers pursuing a resection strategy for asymptomatic lesions.

QS34. Prostaglandin F2a Analog Focally Depletes Adipose Volume Without Concurrent Cytolysis

Purpose: Adipose is one of the most mutable and commonly treated tissues in plastic surgery. Adipose tissue is often the thickest and most variable of the cutaneous layers and is a key contributor to smooth contour, feature, and expression. Unwanted focal adiposity is a common complaint and can arise physiologically, pathologically as lipomas, or iatrogenically after fat grafting. While some indications are amenable to liposuction or resection, not all patients want invasive procedures. Non-invasive ablative procedures have arisen to fill this need including cryolipolysis and the injectable cytolytic deoxycholic acid (Kybella). This agent, however, caries significant comorbid risk. In this study, we investigated repurposing a potent FDA approved prostaglandin F2α (PGF2a) analogue, Latanoprost, currently used as first-line treatment for glaucoma, as an alternative adipolytic agent for small volume focal adipose reduction. Methods: Human adipose obtained under IRB exemption was incubated for 14-days and treated with Kybella and either low- or high-dose soluble Latanoprost every 48-hours. Mature adipocytes and the stromal vascular fractions were collected via enzymatic dissolution and size, count, morphology, and viability were assessed using Calcein-AM/PI imaging. Additionally, single administration of Kybella (500µl) or Latanoprost (1.5 or 150mcg) was performed in vitro to murine fat pads and maintained 2-weeks. These samples were harvested and evaluated via H&E, Pentachrome to assess inguinal fat volume, and fibrotic tissue architecture. Samples were further interrogated via immunofluorescence against Perilipin, Hypoxia Inducible Factor 1-alpha (Hif1a), Uncoupling Protein 1 (UCP1), and hexokinase 2 to assess the variable contributions of Latanoprost therapy to white/brown adipose ratio, focal hypoxia, and metabolic flux. Results: Incubation of lipoaspirate with Kybella resulted in total tissue dissolution and loss of viability. In contrast, Latanoprost did not negatively affect viability of stromal cells or adipocytes. In vivo, both 150 mcg Latanoprost and Kybella significantly decreased inguinal fat pad volume at 2-weeks. Kybella treatment resulted in consistent dermal lesions and histologic evidence of inflammation that were not present in Latanoprost treatment. Furthermore, Latanoprost and vehicle-control treated samples did not significantly vary in presence of fibrotic collagen, Hif1a activation, or presence of UCP1-positive brown fat. Conclusion: Single administration of soluble Latanoprost safely reduced fat pad volume at two weeks post injection in vivo with no ex vivo loss of viability in human tissues. This supports a potential application for reduction in focal adiposity without undesirable cytolysis and future studies will be conducted to optimize dose and determine duration of the effect.

Evidence for metabolic disturbances in the pathogenesis of immune-mediated disease in SAMP1/YitFcs Mice

Abstract Background Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), affect ~1% of the people in the United States. SAMP1/YitFcs mice are a model of CD with terminal ileitis which is rare in other animal models of IBD. Switch of cell energy metabolism towards aerobic glycolysis is a hallmark of inflammation and has been implicated in immune-mediated diseases. Thus, we sought to determine how energy metabolism is altered in the SAMP mice. Methods Glucose metabolism in vivo was determined by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Tissue taking up the 18F-FDG were collected for histology. Metabolic phenotype of activated B and CD4+ T lymphocytes isolated from mesenteric lymph nodes of control and SAMP mice was evaluated by extracellular flux analysis (SeaHorse). To relate the SAMP model to human disease, normal and inflamed ileum from mice and humans were assayed by RNAseq focusing on metabolism-related genes. Results PET scans showed a varying tissue distribution of 18F-FDG uptake in SAMP mice, including ileum, salivary glands and kidneys which all had histological evidence of inflammation. Compared to control, both SAMP B and T cells displayed an increase in glycolysis and oxidative phosphorylation (OXPHOS) rates which is supported by an overall increase in genes related to glucose metabolism, TCA cycle, OXPHOS and fatty acid oxidation in the ileum. Conclusion SAMP mice have a multi-organ immune-mediated disease relying on an increase in cell energy metabolism. Therefore, targeting aerobic glucose metabolism to limit inflammation emerges as a new strategy for CD treatment.

Changes to the activity and sensitivity of nerves innervating subchondral bone contribute to pain in late-stage osteoarthritis.

Although it is clear that osteoarthritis (OA) pain involves activation and/or sensitization of nociceptors that innervate knee joint articular tissues, much less is known about the role of the innervation of surrounding bone. In this study, we used monoiodoacetate (MIA)-induced OA in male rats to test the idea that pain in OA is driven by differential contributions from nerves that innervate knee joint articular tissues vs the surrounding bone. The time-course of pain behavior was assayed using the advanced dynamic weight-bearing device, and histopathology was examined using haematoxylin and eosin histology. Extracellular electrophysiological recordings of knee joint and bone afferent neurons were made early (day 3) and late (day 28) in the pathogenesis of MIA-induced OA. We observed significant changes in the function of knee joint afferent neurons, but not bone afferent neurons, at day 3 when there was histological evidence of inflammation in the joint capsule, but no damage to the articular cartilage or subchondral bone. Changes in the function of bone afferent neurons were only observed at day 28, when there was histological evidence of damage to the articular cartilage and subchondral bone. Our findings suggest that pain early in MIA-induced OA involves activation and sensitization of nerves that innervate the joint capsule but not the underlying subchondral bone, and that pain in late MIA-induced OA involves the additional recruitment of nerves that innervate the subchondral bone. Thus, nerves that innervate bone should be considered important targets for development of mechanism-based therapies to treat pain in late OA.

Remote effects and biodistribution of pulmonary instilled silver nanoparticles in mice

Silver nanoparticles (AgNPs) are the most commonly used nanoparticles (NPs) owing to their anti-microbial properties, and the pulmonary system provides a major portal of entry for these NPs used in aerosolized products. AgNPs have the potential to cause pulmonary toxicity, cross the alveolar-capillary barrier, and distribute to remote organs following pulmonary exposure. The mechanism underlying the effects of AgNPs, secondary to lung exposure, on the major organs including liver, spleen, kidney and brain, however, is still not completely understood. The aim of this study was to analyze the organ toxicity and distribution of pulmonary exposure to single dose of 5 mg/kg AgNPs (10 nm) with varying coatings (polyvinylpyrrolidone and citrate), at different time points (1 and 7 days), in Balb/C mice. Silver ions (Ag+) were used as ionic control. Histological evidence of inflammation was observed in lungs for both types of AgNPs. Markers of inflammation including tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were significantly increased in lung, brain and liver in AgNPs exposed animals. Ag+ ions caused significant increase of TNF-α and IL-6 in the spleen and kidney. Significant increase of reduced glutathione, nitric oxide, and 8-isoprostane was observed in most of the organs investigated. Furthermore, AgNPs induced DNA damage and apoptosis in the lung, liver and brain. The biodistribution showed that, AgNPs were distributed mainly in the spleen, liver, lung and little in kidney and brain. Comparatively, reduced amount of Ag was detected in most organs 7 days after exposure, except for AgAc in the kidney and brain. In conclusion, pulmonary exposure to AgNPs caused oxidative stress markers, inflammation, DNA damage and biodistribution in remote organs. These findings provide a novel mechanistic insight into the pathophysiological effects and tissue distribution of lung exposure to AgNPs.

A novel mouse model for checkpoint inhibitor-induced adverse events.

Immune checkpoint inhibitors have demonstrated significant efficacy in the treatment of a variety of cancers, however their therapeutic potential is limited by abstruse immune related adverse events. Currently, no robust animal model exists of checkpoint inhibitor-induced adverse events. Establishing such a model will improve our mechanistic understanding of this process, which in turn will inform design of improved therapies. We developed a mouse model to determine inflammatory toxicities in response to dual checkpoint blockade in the presence of syngeneic tumors. Mice from susceptible genetic backgrounds received intraperitoneal injections of anti-mouse PD-1 and CTLA-4 antibodies. The mice were monitored for weight loss and histologic evidence of inflammation. Blood was collected for basic metabolic panels and titers of anti-nuclear antibodies. In parallel, mice were also treated with prednisolone, which is commonly used to treat immune related adverse events among cancer patients. Among all the genetic backgrounds, B6/lpr mice treated with anti-CTLA-4 and anti-PD-1 antibodies developed more substantial hepatitis, pancreatitis, colitis, and pneumonitis characterized by organ infiltration of immune cells. Mice that developed tissue infiltration demonstrated high serum levels of glucose and high titers of anti-nuclear antibodies. Finally, while administration of prednisolone prevented the development of the inflammatory adverse events, it also abrogated the protective anti-tumor effect of the checkout inhibitors. Genetic background and treatment modalities jointly modified the inflammatory adverse events in tumor bearing mice, suggesting a complex mechanism for checkpoint inhibitor-related inflammation. Future studies will assess additional genetic susceptibility factors and will examine possible contributions from the administration of other anti-inflammatory drugs.

Tissue-Specific Immunopathology in Fatal COVID-19.

Rationale: In life-threatening coronavirus disease (COVID-19), corticosteroids reduce mortality, suggesting that immune responses have a causal role in death. Whether this deleterious inflammation is primarily a direct reaction to the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or an independent immunopathologic process is unknown.Objectives: To determine SARS-CoV-2 organotropism and organ-specific inflammatory responses and the relationships among viral presence, inflammation, and organ injury.Methods: Tissue was acquired from 11 detailed postmortem examinations. SARS-CoV-2 organotropism was mapped by using multiplex PCR and sequencing, with cellular resolution achieved by in situ viral S (spike) protein detection. Histologic evidence of inflammation was quantified from 37 anatomic sites, and the pulmonary immune response was characterized by using multiplex immunofluorescence.Measurements and Main Results: Multiple aberrant immune responses in fatal COVID-19 were found, principally involving the lung and reticuloendothelial system, and these were not clearly topologically associated with the virus. Inflammation and organ dysfunction did not map to the tissue and cellular distribution of SARS-CoV-2 RNA and protein between or within tissues. An arteritis was identified in the lung, which was further characterized as a monocyte/myeloid-rich vasculitis, and occurred together with an influx of macrophage/monocyte-lineage cells into the pulmonary parenchyma. In addition, stereotyped abnormal reticuloendothelial responses, including excessive reactive plasmacytosis and iron-laden macrophages, were present and dissociated from viral presence in lymphoid tissues.Conclusions: Tissue-specific immunopathology occurs in COVID-19, implicating a significant component of the immune-mediated, virus-independent immunopathologic process as a primary mechanism in severe disease. Our data highlight novel immunopathologic mechanisms and validate ongoing and future efforts to therapeutically target aberrant macrophage and plasma-cell responses as well as promote pathogen tolerance in COVID-19.

P011 Dysbiosis and Goblet cells depletion triggers early intestinal barrier dysfunction that precedes gut inflammation in IL-10 deficient mice (IL-10−/−)

Abstract Background Interleukin-10 deficient mouse (IL-10−/−) is a widely used model of spontaneous ileocolitis that resembles human inflammatory bowel disease (IBD); intestinal barrier dysfunction is an early pathophysiological event, but its underlying mechanisms are still unknown. The objective of this work is to study the natural history of ileocolitis in IL-10−/−, and unravel the influence of intestinal barrier dysfunction and dysbiosis in the development of overt inflammation. Methods Wild-type (WT) and IL-10−/− mice were followed until sacrifice at 3, 5, 10, 20, 57 and 70 weeks of life. Bodyweight, colonic weight/length ratio and in vivo intestinal permeability (measured by rectal administration of FITC-dextran) were registered. After the sacrifice, the colon was harvested and the evaluation of the expression of inflammatory (interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α), inducible nitric synthase (iNOS) and cyclooxygenase-2 (COX-2) and epithelial permeability (ZO-1, E-cadherin, Occludin, Claudins 2 and 7, and Reticulon-4B (RTN-4B) markers was performed by qPCR; expression of mucin-2 (MUC-2) and molecules involved in goblet cell maturation such as interleukin-18 (IL-18) and WAP Four-Disulphide Core Domain 2 (WFDC2), as well as the endoplasmic reticulum stress marker X-box-binding protein (Xbp)-1) by qPCR were also analysed. We also used colon slices for histologic evaluation with haematoxylin-eosin and alcian blue stainings. The microbiota composition was studied by sequencing of the V3-V4 regions of ribosomal 16S from faecal samples of all these mice. Results Compared with WT, IL-10−/− mice showed lower weight gain at all ages and a higher colonic weight/length ratio and histological evidence of inflammation at weeks 20 and 57. iNOS and IL-1b gene expression in the colon were significantly higher in IL-10−/− mice at weeks 10 and 20, respectively. Nevertheless, increased intestinal permeability was observed from week 10; the number of goblet cells and expression of MUC-2, IL-18, WFDC2 and XBP-1 were significantly lower in knockout mice from week 10. Moreover, dysbiosis in IL-10−/− mice began at week 5, increasing at 10 and showing the lowest diversity and appearance of pathogenic families at 20 weeks of age. Conclusion Dysbiosis and goblet cell depletion in the colon of IL-10−/− mice are associated with early intestinal barrier dysfunction, and precede overt gut inflammation in this animal model of IBD.

1240 Increased Mucosal Innate Immune Activation in Hereditary Alpha Trytpasemia Subjects Is Predictive of Clinical Response to Tofacitanib Therapy

INTRODUCTION: Hereditary alpha hypertryptasemia (HAT) is a genetic disorder associated with elevated serum tryptase as well as GI symptoms including nausea, vomiting, heartburn, abdominal pain, and diarrhea. HAT subjects are often mis-diagnosed with gastroparesis or IBS. HAT is estimated to impact up 6% of Caucasians in the US (Nat Genet. 2016 Dec;48(12):1564-1569.). Elevated tryptase in HAT is not associated with clonal mast cell (MC) disease, but does cause MC activation. MCs and memory T cells are increased in the HAT small intestine. The mechanism whereby tryptase produces clinical symptoms is unknown. We hypothesize that tryptase expression results in an intestinal epithelial cell (IEC) innate immune activation called pyroptosis. Tofacitanib is a JAK-STAT inhibitor which is believed to reduce innate immune activation. The aim of this pilot study was to evaluate the level of pyroptosis in HAT patients who have no endoscopic or histologic evidence of inflammation and determine its predictive value for clinical response to tofacitanib. METHODS: HAT was confirmed by genetic testing in all subjects. All subjects had undergone a colonoscopy and had available small bowel biopsies. Biopsy samples were blindly analyzed for pyroptosis using the Maximus Biological assay kit. Samples with at least 10 villi were analyzed for IEC pyroptosis. Subjects' clinical response to therapy was analyzed, stratified by pre-treatment biopsy pyroptosis levels and type of therapy. RESULTS: 11 patients (2 M, 9 F) with an average age of 50 were included. All subjects had confirmed duplication or triplication in their TPSAB1 gene. The average tryptase was 18.5 mcg/L (&lt;8.5 mcg/L) and the average number of mast cells per HPF by CD117 exceeded 52.4 per HPF (nml small bowel is &lt; 25/hpf). All subjects reported nausea, vomiting, abdominal pain and diarrhea symptoms. Ileal biopsy pyroptosis reveled a three-fold increase in mucosal innate immune activation, an average of 33 ± 10 positive cells/1000 IECs (normal is up to 10/1000 IEC). Only one HAT subject who was on adalimumab therapy at the time of biopsy had a normal pyroptosis level. Three of the patients in this cohort received treatment with tofacitinib who responded all had elevated pyroptosis levels (22 ± 2.9 positive cells/1000 IECs). Tryptase levels were reduced by 25% to 50% with a dramatic improvement in their GI symptoms. CONCLUSION: Mucosal innate immune activation is evident in HAT subjects and can predict response to tofacitinib therapy.

A Novel Peptide Ameliorates LPS-Induced Intestinal Inflammation and Mucosal Barrier Damage via Its Antioxidant and Antiendotoxin Effects.

Intestinal inflammation is an inflammatory disease resulting from immune dysregulation in the gut. It can increase the risk of enteric cancer, which is a common malignancy globally. As a new class of anti-inflammatory agents, native peptides have potential for use in the treatment of several intestinal inflammation conditions; however, their potential cytotoxicity and poor anti-inflammatory activity and stability have prevented their development. Hybridization has been proposed to overcome this problem. Thus, in this study, we designed a hybrid peptide (LL-37-TP5, LTP) by combing the active centre of LL-37 (13–36) with TP5. The half-life and cytotoxicity were tested in vitro, and the hybrid peptide showed a longer half-life and lower cytotoxicity than its parental peptides. We also detected the anti-inflammatory effects and mechanisms of LTP on Lipopolysaccharide (LPS)-induced intestinal inflammation in murine model. The results showed that LTP effectively prevented LPS-induced weight loss, impairment of intestinal tissues, leukocyte infiltration, and histological evidence of inflammation. Additionally, LTP decreased the levels of tumour necrosis factor-alpha, interferon-gamma, and interleukin-6; increased the expression of zonula occludens-1 and occludin; and reduced permeability in the jejunum of LPS-treated mice. Notably, LTP appeared to be more potent than the parental peptides LL-37 and TP5. The anti-inflammatory effects of LTP may be associated with the neutralization of LPS, inhibition of oxidative stress, and inhibition of the NF-κB signalling pathway. The findings of this study suggest that LTP might be an effective therapeutic agent for treating intestinal inflammation.

Age-Dependent Effects of Immunoproteasome Deficiency on Mouse Adenovirus Type 1 Pathogenesis.

Acute respiratory infection with mouse adenovirus type 1 (MAV-1) induces activity of the immunoproteasome, an inducible form of the proteasome that shapes CD8 T cell responses by enhancing peptide presentation by major histocompatibility complex (MHC) class I. We used mice deficient in all three immunoproteasome subunits (triple-knockout [TKO] mice) to determine whether immunoproteasome activity is essential for control of MAV-1 replication or inflammatory responses to acute infection. Complete immunoproteasome deficiency in adult TKO mice had no effect on MAV-1 replication, virus-induced lung inflammation, or adaptive immunity compared to C57BL/6 (B6) controls. In contrast, immunoproteasome deficiency in neonatal TKO mice was associated with decreased survival and decreased lung gamma interferon (IFN-γ) expression compared to B6 controls, although without substantial effects on viral replication, histological evidence of inflammation, or expression of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-1β in lungs or other organs. T cell recruitment and IFN-γ production was similar in lungs of infected B6 and TKO mice. In lungs of uninfected B6 mice, we detected low levels of immunoproteasome subunit mRNA and protein that increased with age. Immunoproteasome subunit expression was lower in lungs of adult IFN-γ-deficient mice compared to B6 controls. Together, these results demonstrate developmental regulation of the immunoproteasome that is associated with age-dependent differences in MAV-1 pathogenesis.IMPORTANCE MAV-1 infection is a useful model to study the pathogenesis of an adenovirus in its natural host. Host factors that control MAV-1 replication and contribute to inflammation and disease are not fully understood. The immunoproteasome is an inducible component of the ubiquitin proteasome system that shapes the repertoire of peptides presented by MHC class I to CD8 T cells, influences other aspects of T cell survival and activation, and promotes production of proinflammatory cytokines. We found that immunoproteasome activity is dispensable in adult mice. However, immunoproteasome deficiency in neonatal mice increased mortality and impaired IFN-γ responses in the lungs. Baseline immunoproteasome subunit expression in lungs of uninfected mice increased with age. Our findings suggest the existence of developmental regulation of the immunoproteasome, like other aspects of host immune function, and indicate that immunoproteasome activity is a critical protective factor early in life.

Feline inflammatory bowel disease

Inflammatory bowel disease (IBD) is one of the most common causes of chronic clinical signs from the gastrointestinal tract, associated with histological evidence of inflammation in the lamina propria of the small and/or large intestine in cats. The underlying etiopathogenesis of this inflammation remains unclear. IBD is probably caused by a combination of environmental and immune factors in genetically susceptible individuals. The process of diagnosing IBD involves several steps and is based on the exclusion of other causes of gastrointestinal signs and on the confirmation of the presence of inflammatory infiltration in the intestinal wall by histopathological assessment of biopsies. The treatment is based on anti-inflammatory and immunosuppressive drugs. In addition, dietotherapy, antibiotics, antiparasitic drugs, prebiotics, probiotics and supplementation of vitamin b12 are also used. For most patients, the response to treatment is satisfactory, but the maintenance of clinical remission in most of them may require anti-inflammatory drugs for the rest of their lives.

The Utility and Limitations of CRP, ESR and DAS28-CRP in Appraising Disease Activity in Rheumatoid Arthritis.

Introduction: Identifying and quantifying inflammatory disease activity in rheumatoid arthritis remains a challenge. Many studies have suggested that a large proportion of patients may have active inflammation, but normal inflammatory markers. Although various disease activity scores have been validated, most rely to a large degree on biomarkers such as CRP and ESR. In this study, we examine the utility and limitations of these biomarkers, as well as the DAS28-CRP in appraising disease activity in RA.Methods: Two hundred and twenty three consecutive rheumatoid arthritis reporting knee arthralgia underwent synovial sampling of the affected knee via needle arthroscopy. The synovium was examined by microscopy with H+E staining as well as immunohistochemistry, and related to the ESR, CRP and DAS28-CRP on blood samples taken immediately before arthroscopy.Results: Although a statistically significant positive correlation was observed between CRP and the level of inflammation in the biopsy retrieved (n = 197, rho = 0.43, CI 0.30–0.54, p < 0.0001), there was histological evidence of inflammation in the synovium in 49.4% of the patients who had a normal CRP. A positive correlation was also observed between ESR and the level of inflammation in the biopsy retrieved (n = 188, rho = 0.29, CI 0.15–0.42 p < 0.0001). A statistically significant but weak positive correlation was observed between the DAS28-CRP and synovial inflammation (n = 189, rho = 0.23, CI 0.09–0.37, p = 0.0011). Only the CD19 infiltrate in the synovium correlated with serum CRP (n = 70, rho = 0.32, CI 0.08–0.52, p = 0.0068).Conclusion: CRP has a moderately strong relationship with disease activity, but there are significant pitfalls in the use of this biomarker in RA, and therefore a need interpret CRP results judiciously. The results of this study underline the heterogeneity of RA, and the need to develop improved panels of biomarkers, to better stratify RA, and to identify the cohort for whom inflammatory activity cannot be measured accurately with CRP.

Dipyridamole enhances osteogenesis of three-dimensionally printed bioactive ceramic scaffolds in calvarial defects

PurposeThe objective of this study was to test the osteogenic capacity of dipyridamole-loaded, three-dimensionally printed, bioactive ceramic (3DPBC) scaffolds using a translational, skeletally mature, large-animal calvarial defect model. Materials and methodsCustom 3DPBC scaffolds designed to present lattice-based porosity only towards the dural surface were either coated with collagen (control) or coated with collagen and immersed in a 100 μM concentration dipyridamole (DIPY) solution. Sheep (n = 5) were subjected to 2 ipsilateral trephine-induced (11-mm diameter) calvarial defects. Either a control or a DIPY scaffold was placed in each defect, and the surgery was repeated on the contralateral side 3 weeks later. Following sacrifice, defects were evaluated through microcomputed tomography and histologic analysis for bone, scaffold, and soft tissue quantification throughout the defect. Parametric and non-parametric methods were used to determine statistical significance based on data distribution. ResultsNo exuberant or ectopic bone formation was observed, and no histologic evidence of inflammation was noted within the defects. Osteogenesis was higher in DIPY-coated scaffolds compared to controls at 3 weeks (p = 0.013) and 6 weeks (p = 0.046) in vivo. When bone formation was evaluated as a function of defect radius, average bone formation was higher for DIPY relative to control scaffolds at both time points (significant at defect central regions at 3 weeks and at margins at 6 weeks, p = 0.046 and p = 0.031, respectively). ConclusionDipyridamole significantly improves the calvarial bone regeneration capacity of 3DPBC scaffolds. The most significant difference in bone regeneration was observed centrally within the interface between the 3DPBC scaffold and the dura mater.

Abstract: Dipyridamole Enhances Osteogenesis of 3D-Printed Bioactive Ceramic Scaffolds in Calvarial Defects

INTRODUCTION: The objective of this study was to test the osteogenic capacity of dipyridamole-loaded, 3D-printed bioactive ceramic (3DPBC) scaffolds utilizing a translational, skeletally-mature, large animal calvarial defect model. METHODS: Custom 3DPBC scaffolds designed to present lattice-based porosity only towards the dural surface were either coated with collagen (control) or coated with collagen and immersed in a 100 µM concentration dipyridamole (DIPY) solution. Sheep (n=5) were subjected to 2 ipsilateral trephine-induced (11 mm diameter) calvarial defects. Either a control or a DIPY scaffold was placed in each defect and the surgery was repeated on the contralateral side 3 weeks later. Following sacrifice, defects were evaluated through microcomputed tomography and histologic analysis for bone, scaffold, and soft tissue quantification throughout the defect. Parametric and non-parametric methods were utilized to determine statistical significance based on data distribution. RESULTS: No exuberant or ectopic bone formation was observed and no histologic evidence of inflammation was noted within the defects. Osteogenesis was higher in DIPY-coated scaffolds compared to controls at 3 weeks (p=0.013) and 6 weeks (p=0.046) in vivo. When bone formation was evaluated as a function of defect radius, average bone formation was higher for DIPY relative to control scaffolds at both time points (significant at defect central regions at 3 weeks and at margins at 6 weeks; p=0.046 and p=0.031, respectively). CONCLUSION: Dipyridamole significantly improves the calvarial bone regeneration capacity of 3D-printed bioactive ceramic scaffolds. The most significant difference in bone regeneration was observed centrally within the interface between the 3DPBC scaffold and the dura mater.

A 27-Year-Old Man with a Rare Cause of Smouldering Abdominal Pain: Propionibacterium Acnes Positive Abdominal Cerebrospinal Fluid Pseudocyst

A 27-year-old man with Crouzon syndrome with multiple craniofacial surgeries and ventriculoperitoneal (VP) shunt placement for hydrocephalus presented with abdominal pain. He experienced a few weeks of gradual worsening abdominal discomfort. Three days prior to presentation, his pain became severe and localized to the right upper quadrant. In the ED, he was hemodynamically stable but had leukocytosis. Abdominal ultrasound revealed a 14-cm hypoechoic, septated fluid collection in the right abdomen. Abdominal CT revealed a thin-walled cystic mass surrounding the VP shunt tip suggestive of a cerebrospinal fluid (CSF) pseudocyst. CT head did not reveal acute pathology. Surgical services were consulted and performed shunt externalization: construction of a distal catheter to drain CSF from the pseudocyst into a proximal catheter connected to a percutaneous bag. Intraoperatively, approximately 250 mL of CSF was drained. The original catheter tip was cut off and tested positive for Propionibacterium acnes. He received a 14-day course of IV ceftriaxone. Later, he underwent successful shunt reinsertion into the left abdominal parietal-pleural space without pseudocyst recurrence. DISCUSSION VP shunt is a rare cause of abdominal pseudocyst with a reported incidence of 1-4.5%, usually developing between 3 weeks to 5 years after shunt placement/revision [1]. Children commonly present with symptoms related to increased intracranial pressure and abdominal pain while adults predominantly present with abdominal complaints [1]. Although the exact etiology of VP shunt-associated pseudocyst is incompletely understood, histologic evidence of inflammation is nearly always present, possibly to the catheter or CSF [2]. Infection may occur, often with Staphylococcus epidermidis, Staphylococcus aureus, or Propionibacterium acnes [2]. Management of abdominal CSF pseudocysts is either immediate shunt activation or shunt externalization and antibiotic therapy [2]. Pseudocysts often require laparoscopic-assisted fluid drainage with pseudocyst wall excision. If clinical and radiographic monitoring reveals recurrence of abdominal pseudocyst, CSF may need to be diverted into other cavities.Figure 1Figure 2Figure 3

99MTc-Hexamethylpropyleneamine Oxime Imaging for Early Detection of Acute Lung Injury in Rats Exposed to Hyperoxia or Lipopolysaccharide Treatment.

Tc-Hexamethylpropyleneamine oxime (HMPAO) is a clinical single-photon emission computed tomography biomarker of tissue oxidoreductive state. Our objective was to investigate whether HMPAO lung uptake can serve as a preclinical marker of lung injury in two well-established rat models of human acute lung injury (ALI).Rats were exposed to >95% O2 (hyperoxia) or treated with intratracheal lipopolysaccharide (LPS), with first endpoints obtained 24 h later. HMPAO was administered intravenously before and after treatment with the glutathione-depleting agent diethyl maleate (DEM), scintigraphy images were acquired, and HMPAO lung uptake was quantified from the images. We also measured breathing rates, heart rates, oxygen saturation, bronchoalveolar lavage (BAL) cell counts and protein, lung homogenate glutathione (GSH) content, and pulmonary vascular endothelial filtration coefficient (Kf).For hyperoxia rats, HMPAO lung uptake increased after 24 h (134%) and 48 h (172%) of exposure. For LPS-treated rats, HMPAO lung uptake increased (188%) 24 h after injury and fell with resolution of injury. DEM reduced HMPAO uptake in hyperoxia and LPS rats by a greater fraction than in normoxia rats. Both hyperoxia exposure (18%) and LPS treatment (26%) increased lung homogenate GSH content, which correlated strongly with HMPAO uptake. Neither of the treatments had an effect on Kf at 24 h. LPS-treated rats appeared healthy but exhibited mild tachypnea, BAL, and histological evidence of inflammation, and increased wet and dry lung weights. These results suggest the potential utility of HMPAO as a tool for detecting ALI at a phase likely to exhibit minimal clinical evidence of injury.