Distinct Serum Immune Profiles Define the Spectrum of Acute and Chronic Pancreatitis From the Multicenter Prospective Evaluation of Chronic Pancreatitis for Epidemiologic and Translational Studies (PROCEED) Study.

BACKGROUND & AIMS: Pancreatitis is a disease continuum, starting with acute pancreatitis (AP) and progressing in some cases to recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP). Currently, there are no approved therapies or early diagnostic or prognostic biomarkers for pancreatitis. The current study examined whether patient serum immune profiling could identify noninvasive biomarkers and provide mechanistic insight into the disease continuum of pancreatitis. METHODS: Using Olink immunoassay, we assessed the protein levels of 92 immune markers in serum samples from participants enrolled in the Prospective Evaluation of Chronic Pancreatitis for Epidemiologic and Translational Studies (PROCEED) study of the Chronic Pancreatitis, Diabetes, and Pancreatic Cancer (CPDPC) consortium. Samples (N = 231) were obtained from individuals without pancreatic disease (n = 56) and from those with chronic abdominal pain (CAP) (n = 24), AP (n = 38), RAP (n = 56), and CP (n = 57). RESULTS: A total of 33 immune markers differentiated the combined pancreatitis groups from controls. Immune markers related to interleukin (IL) 17 signaling distinguished CP from AP and RAP. Similarly, the serum level of IL17A and C-C motif chemokine ligand 20 differentiated CP from CAP, suggesting the involvement of T helper 17 cells in CP pathogenesis. The receiver operator characteristic curve with 2 immune markers (IL17A and sulfotransferase 1A1) could differentiate CP from CAP (optimistic area under the curve = 0.78). The macrophage classical activation pathway elevated along the continuum of pancreatitis, suggesting an accumulation of proinflammatory signals over disease progression. Several immune markers were associated with smoking, alcohol, and diabetes status. CONCLUSIONS: Immune profiling of serum samples from a large pancreatitis cohort led to identifying distinct immune markers that could serve as potential biomarkers to differentiate the varying pancreatitis disease states. In addition, the finding of IL17 signaling in CP could provide insight into the immune mechanisms underlying disease progression.

Novel Circulating and Tissue Monocytes as Well as Macrophages in Pancreatitis and Recovery.

BACKGROUND AND AIMS: Acute pancreatitis (AP) is an inflammatory disease with mild to severe course that is associated with local and systemic complications and significant mortality. Uncovering inflammatory pathways that lead to progression and recovery will inform ways to monitor and/or develop effective therapies. METHODS: We performed single-cell mass Cytometry by Time Of Flight (CyTOF) analysis to identify pancreatic and systemic inflammatory signals during mild AP (referred to as AP), severe AP (SAP), and recovery using 2 independent experimental models and blood from patients with AP and recurrent AP. Flow cytometric validation of monocytes subsets identified using CyTOF analysis was performed independently. RESULTS: Ly6C+ inflammatory monocytes were the most altered cells in the pancreas during experimental AP, recovery, and SAP. Deep profiling uncovered heterogeneity among pancreatic and blood monocytes and identified 7 novel subsets during AP and recovery, and 6 monocyte subsets during SAP. Notably, a dynamic shift in pancreatic CD206+ macrophage population was observed during AP and recovery. Deeper profiling of the CD206+ macrophage identified 7 novel subsets during AP, recovery, and SAP. Differential expression analysis of these novel monocyte and CD206+ macrophage subsets revealed significantly altered surface (CD44, CD54, CD115, CD140a, CD196, podoplanin) and functional markers (interferon-γ, interleukin 4, interleukin 22, latency associated peptide-transforming growth factor-ß, tumor necrosis factor-α, T-bet, RoRγt) that were associated with recovery and SAP. Moreover, a targeted functional analysis further revealed distinct expression of pro- and anti-inflammatory cytokines by pancreatic CD206+ macrophage subsets as the disease either progressed or resolved. Similarly, we identified heterogeneity among circulating classical inflammatory monocytes (CD14+CD16-) and novel subsets in patients with AP and recurrent AP. CONCLUSIONS: We identified several novel monocyte/macrophage subsets with unique phenotype and functional characteristics that are associated with AP, recovery, and SAP. Our findings highlight differential innate immune responses during AP progression and recovery that can be leveraged for future disease monitoring and targeting.

Radiological profile of patients undergoing Chest X-ray and computed tomography scans during COVID-19 outbreak.

BACKGROUND & OBJECTIVE: Radiology has played a significant role in the diagnosis and quantifying the severity of COVID 19 pulmonary disease. This study was conducted to assess patterns and severity of COVID-19 pulmonary disease based on radiological imaging. METHODS: A prospective observational study was conducted in a large tertiary care public sector teaching hospital of Karachi, Pakistan from June 2020 till August 2020. All confirmed and suspected COVID-19 patients referred for chest X-rays and computed tomography (CT) scans were evaluated along with RT-PCR results. Suspected patients were followed for RT-PCR. Radiological features and severity of imaging studies were determined. RESULTS: Of 533 patients in whom X-rays were performed, majority had severe/critical findings, i.e., 304 (57.03%). Of 97 patients in whom CT scan was performed, mild/moderate findings were observed in 63 (64.94%) patients. Of 472 patients with abnormal X-rays, majority presented with alveolar pattern 459 (97.2%), bilateral lung involvement 453 (89.6%), and consolidation 356 (75.4%). Moreover, lobar predominance showed lower zone preponderance in 446 (94.5%) patients. Of 88 patients with abnormal CT findings, ground-glass opacity (GGO) 87 (98.9%) and crazy paving 69 (78.4%) were the most common findings. An insignificantly higher association of PCR positive cases was observed with severe/critical X-rays (p-value 0.076) and CT scan findings (p-value 0.431). CONCLUSION: Most common patterns on CT scans were GGO and crazy paving. While on chest radiographs, bilateral lung involvement with alveolar pattern and consolidation were most common findings. On X-rays, majority had severe/critical whereas CT scan had mild/moderate findings.

CT-Based Evaluation of Diffuse Idiopathic Skeletal Hyperostosis in Adult Population; Prevalence, Associations and Interobserver Agreement.

Diffuse idiopathic skeletal hyperostosis (DISH), being an asymptomatic condition, is generally discovered incidentally on imaging and it has not received much attention for research on clinical grounds. We assessed the prevalence of DISH, its associated factors, and interobserver agreement for computed tomography (CT)-based diagnosis of DISH. CT scans of chest, abdomen, and pelvis performed for various clinical indications were retrospectively reviewed. Resnick criteria were used for the diagnosis of DISH. Moreover, enthesopathy along with comorbidities was assessed. CT scans were observed by 3 observers having different experience levels. Out of total 416 patients, the prevalence of DISH was 30.8%. Strong positive agreement was observed between observer 1 and 2 (k = 0.89), observer 1 and 3 (k = 0.91), and observer 2 and 3 (k = 0.94). Reporting rate of DISH was 59.3%. Regression analyses showed that enthesopathy was 2.45 times (adjusted odds ratio [AOR]: 2.45, 95% confidence intervals [CI]: 1.48-4.05), diabetic patients were 4.74 times (AOR: 4.74, 95% CI: 2.89-7.78) while hypertensive patients were 2.17 times (AOR: 2.17, 95% CI: 1.30-3.62) more likely to have DISH in comparison to those who do not have DISH. A high prevalence of DISH was observed in our cohort. Enthesopathy and comorbidities like diabetes and hypertension were significant factors associated with DISH. Moreover, excellent agreement was observed in defining DISH on CT according to Resnick criteria.

Intercalated Poly (2-Acrylamido-2-methyl-1-propanesulfonic Acid) into Sulfonated Poly (1,4-Phenylene ether-ether-sulfone) Based Proton Exchange Membrane: Improved Ionic Conductivity.

A series of hybrid proton exchange membranes were synthesized via in situ polymerization of poly (2-acrylamido-2-methyl-1-propanesulfonic acid) PMPS with sulfonated poly (1,4-phenylene ether-ether-sulfone) (SPEES). The insertion of poly (2-acrylamido-2-methyl-1-propanesulfonic acid) PMPS, between the rigid skeleton of SPEES plays a reinforcing role to enhance the ionic conductivity. The synthesized polymer was chemically characterized by fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance 1H NMR spectroscopy to demonstrate the successful grafting of PMPS with the pendent polymer chain of SPEES. A variety of physicochemical properties were also investigated such as ion exchange capacity (IEC), proton conductivity, water uptake and swelling ratio to characterize the suitability of the formed polymer for various electrochemical applications. SP-PMPS-03, having the highest concentration of all PMPS, shows excellent proton conductivity of 0.089 S cm-1 at 80 °C which is much higher than SPEES which is ~0.049 S cm-1. Optimum water uptake and swelling ratio with high conductivity is mainly attributed to a less ordered arrangement polymer chain with high density of the functional group to facilitate ionic transport. The residual weight was 93.35, 92.44 and 89.56%, for SP-PMPS-01, 02 and 03, respectively, in tests with Fenton's reagent after 24 h. In support of all above properties a good chemical and thermal stability was also achieved by SP-PMPS-03, owing to the durability for electrochemical application.

STING signalling protects against chronic pancreatitis by modulating Th17 response.

OBJECTIVE: Chronic pancreatitis (CP) is an inflammatory disease with progressive fibrosis leading to exocrine and endocrine dysfunction. Currently, there are no approved effective therapies for CP. Stimulator of interferon genes (STING) signalling is a key innate immune sensor of DNA. In this study, we evaluated the role of STING signalling in CP. DESIGN: We used an experimental model of CP to test the effect of STING signalling in STING wild-type and knockout mice as well as bone marrow chimaeras (BMCs). STING was activated using a pharmacological agent. Since we found changes in Th17 cells, we used neutralising and control antibodies to determine the role of IL-17A. The effect of STING signalling was further explored in IL-17A generation and we examined the effect of IL-17A on pancreatic stellate cells (PSCs). Human pancreas from patients with CP and without CP were also stained for IL-17A. RESULTS: STING activation decreased CP-associated pancreatic inflammation and fibrosis, whereas absence of STING led to worsening of the disease. BMCs showed that leucocytes play an important role in STING signalling-mediated amelioration of experimental CP. STING deletion was associated with increased Th17 cell infiltration in the pancreas, whereas STING agonist limited this Th17 response. Importantly, anti-IL-17A antibody treatment mitigated the severity of CP in the absence of STING signalling. STING deficiency promoted Th17 polarisation and PSCs express functional IL-17 receptor by upregulating fibrosis genes. Compared with tumour margins, pancreas from patients with CP had significant increase in IL-17A+ cells. CONCLUSION: Unlike acute pancreatitis, STING activation is protective in CP. STING signalling is important in regulating adaptive immune responses by diminishing generation of IL-17A during CP and presents a novel therapeutic target for CP.

Attenuation of Allergen-, IL-13-, and TGF-α-induced Lung Fibrosis after the Treatment of rIL-15 in Mice.

Endogenous IL-15 deficiency promotes lung fibrosis; therefore, we examined the effect of induced IL-15 in restricting the progression of lung fibrosis. Our objective in this work was to establish a novel therapeutic molecule for pulmonary fibrosis. Western blot, qPCR, and ELISA were performed on the lung tissues of IL-15-deficient mice, and recombinant IL-15 (rIL-15)-treated CC10-IL-13 and CC10-TGF-α mice, and allergen-challenged CC10-IL-15 mice were examined to establish the antifibrotic effect of IL-15 in lung fibrosis. We show that endogenous IL-15 deficiency induces baseline profibrotic cytokine and collagen accumulation in the lung, and pharmacological delivery of rIL-15 downregulates Aspergillus antigen-induced lung collagen, the profibrotic cytokines IL-13 and TGF-ß1, and α-SMA+ and FSP1+ cells in mice. To confirm that overexpression of IL-15 diminishes pulmonary fibrosis, we generated CC10-rtTA-tetO7-IL-15 transgenic mice and challenged them with Aspergillus antigen. Aspergillus antigen-challenged, doxycycline (DOX)-treated CC10-IL-15 transgenic mice exhibited decreased collagen accumulation, profibrotic cytokine (IL-13 and TGF-ß1) expression, and α-SMA+ and FSP1+ cells compared with IL-15-overexpressing mice not treated with DOX. Additionally, to establish that the antifibrotic effect of IL-15 is not limited to allergen-induced fibrosis, we showed that rIL-15 or IL-15 agonist treatment restricted pulmonary fibrosis even in CC10-IL-13 and CC10-TGF-α mice. Mechanistically, we show that T-helper cell type 17 suppressor IL-15-responsive RORγ+ T regulatory cells are induced in DOX-treated, allergen-challenged IL-15-overexpressing mice, which may be a novel pathway for restricting progression of pulmonary fibrosis. Taken together, our data establishes antifibrotic activity of IL-15 that might be a novel therapeutic molecule to combat the development of pulmonary fibrosis.

Intestinal overexpression of IL-18 promotes eosinophils-mediated allergic disorders.

Baseline eosinophils reside in the gastrointestinal tract; however, in several allergic disorders, excessive eosinophils accumulate in the blood as well in the tissues. Recently, we showed in vitro that interleukin (IL)-18 matures and transforms IL-5-generated eosinophils into the pathogenic eosinophils that are detected in human allergic diseases. To examine the role of local induction of IL-18 in promoting eosinophil-associated intestinal disorders, we generated enterocyte IL-18-overexpressing mice using the rat intestinal fatty acid-binding promoter (Fabpi) and analysed tissue IL-18 overexpression and eosinophilia by performing real-time polymerase chain reaction, Enzyme-Linked Immunosorbent Assay and anti-major basic protein immunostaining. Herein we show that Fabpi-IL-18 mice display highly induced IL-18 mRNA and protein in the jejunum. IL-18 overexpression in enterocytes promotes marked increases of eosinophils in the blood and jejunum. Our analysis shows IL-18 overexpression in the jejunum induces a specific population of CD101+  CD274+ tissue eosinophils. Additionally, we observed comparable tissue eosinophilia in IL-13-deficient-Fabpi-IL-18 mice, and reduced numbers of tissue eosinophils in eotaxin-deficient-Fabpi-IL-18 and IL-5-deficient-Fabpi-IL-18 mice compared with Fabpi-IL-18 transgenic mice. Notably, jejunum eosinophilia in IL-5-deficient-Fabpi-IL-18 mice is significantly induced compared with wild-type mice, which indicates the direct role of induced IL-18 in the tissue accumulation of eosinophils and mast cells. Furthermore, we also found that overexpression of IL-18 in the intestine promotes eosinophil-associated peanut-induced allergic responses in mice. Taken together, we provide direct in vivo evidence that induced expression of IL-18 in the enterocytes promotes eotaxin-1, IL-5 and IL-13 independent intestinal eosinophilia, which signifies the clinical relevance of induced IL-18 in eosinophil-associated gastrointestinal disorders (EGIDs) to food allergens.

Regulatory effects of IL-15 on allergen-induced airway obstruction.

BACKGROUND: Airway obstruction is a physiologic feature of asthma, and IL-15 might have an important role in asthma pathogenesis. OBJECTIVE: We tested the hypothesis that regulation of IL-15 is critical for preservation of allergen-induced airway hyperresponsiveness (AHR), airway resistance, and compliance in response to methacholine. METHODS: Airway inflammation, AHR, resistance, and compliance were assessed in Il15 gene-deficient mice and IL-15-overexpressing mice in an allergen-induced murine model of asthma. We assessed eosinophil numbers by using anti-major basic protein immunostaining, goblet cell hyperplasia by using periodic acid-Schiff staining, and cytokine and chemokine levels by performing quantitative PCR and ELISA. RESULTS: We made a novel observation that IL-15 deficiency promotes baseline airway resistance in naive mice. Moreover, rIL-15 delivery to the lung downregulates expression of proinflammatory cytokines and improves allergen-induced AHR, airway resistance, and compliance. These observations were further validated in doxycycline-inducible CC10-IL-15 bitransgenic mice. Doxycycline-exposed, Aspergillus species extract-challenged CC10-IL-15 bitransgenic mice exhibited significantly reduced levels of proinflammatory cytokines (IL-4, IL-5, and IL-13) and decreased goblet cell hyperplasia. Airway obstruction, including AHR and airway resistance, was diminished in allergen-challenged doxycycline-exposed compared with non-doxycycline-exposed CC10-IL-15 bitransgenic mice. Mechanistically, we observed that IL-15-mediated protection of airway obstruction is associated with induced IFN-γ- and IL-10-producing regulatory CD4+CD25+ forkhead box p3 (Foxp3)+ T cells. Additionally, we found that a human IL-15 agonist (ALT-803) improved airway resistance and compliance in an experimental asthma model. CONCLUSION: We report our novel finding that IL-15 has a potent inhibitory effect on the airway obstruction that occurs in response to environmental allergens.

Role of eosinophils in the initiation and progression of pancreatitis pathogenesis.

Eosinophilic pancreatitis (EP) is reported in humans; however, the etiology and role of eosinophils in EP pathogenesis are poorly understood and not well explored. Therefore, it is interesting to examine the role of eosinophils in the initiation and progression of pancreatitis pathogenesis. Accordingly, we performed anti-major basic protein immunostaining, chloroacetate esterase, and Masson's trichrome analyses to detect eosinophils, mast cells, and collagen in the tissue sections of mouse and human pancreas. Induced eosinophils accumulation and degranulation were observed in the tissue sections of human pancreatitis, compared with no eosinophils in the normal pancreatic tissue sections. Similarly, we observed induced tissue eosinophilia along with mast cells and acinar cells atrophy in cerulein-induced mouse model of chronic pancreatitis. Additionally, qPCR and ELISA analyses detected induced transcript and protein levels of proinflammatory and profibrotic cytokines, chemokines like IL 5, IL-18, eotaxin-1, eotaxin-2, TGF-ß1, collagen-1, collagen-3, fibronectin, and α-SMA in experimental pancreatitis. Mechanistically, we show that eosinophil-deficient GATA1 and endogenous IL-5-deficient mice were protected from the induction of proinflammatory and profibrotic cytokines, chemokines, tissue eosinophilia, and mast cells in a cerulein-induced murine model of pancreatitis. These human and experimental data indicate that eosinophil accumulation and degranulation may have a critical role in promoting pancreatitis pathogenesis including fibrosis. Taken together, eosinophil tissue accumulation needs appropriate attention to understand and restrict the progression of pancreatitis pathogenesis in humans. NEW & NOTEWORTHY The present study for the first time shows that eosinophils accumulate in the pancreas and promote disease pathogenesis, including fibrosis in earlier reported cerulein-induced experimental models of pancreatitis. Importantly, we show that GATA-1 and IL-5 deficiency protects mice form the induction of eosinophil active chemokines, and profibrotic cytokines, including accumulation of tissue collagen in an experimental model of pancreatitis. Additionally, we state that cerulein-induced chronic pancreatitis is independent of blood eosinophilia.

IL-15 regulates fibrosis and inflammation in a mouse model of chronic pancreatitis.

Pancreatitis is an inflammatory disease characterized by the induction of several proinflammatory cytokines like interleukin (IL)-6, IL-8, IL-1ß, and IL-1. Recently, the multifunctional innate cytokine IL-15 has been implicated in the protection of several diseases, including cancer. Tissue fibrosis is one of the major problems in successfully treating chronic pancreatitis pathogenesis. Therefore, we tested the hypothesis that recombinant IL-15 (rIL-15) treatment may induce innate tissue responses and its overexpression will improve the pathogenesis of cerulein-induced chronic pancreatitis, associated remodeling, and fibrosis. We observed atrophy of acinar cells, increased inflammation, and increased deposition of perivascular collagen, the upregulated protein level of transforming growth factor (TGF)-ß1, α-smooth muscle actin (α-SMA), and collagen-1 in cerulein-induced chronic pancreatitis in mice. Furthermore, we reported that rIL-15 treatment protects mice from the cerulein-induced chronic pancreatitis pathogenesis, including acinar cell atrophy, and perivascular accumulation of tissue collagen followed by downregulation of profibrotic genes such as TGF-ß1, α-SMA, collagen-1, collagen-3, and fibronectin in cerulein-induced chronic pancreatitis in mice. Mechanistically, we show that IL-15-mediated increase of interferon-γ-responsive invariant natural killer T (iNKT) cells in the blood and tissue protects cerulein-induced pancreatic pathogenesis in mice. Of note, a reduction in iNKT cells was also observed in human chronic pancreatitis compared with normal individuals. Taken together, these data suggest that IL-15 treatment may be a novel therapeutic strategy for treating chronic pancreatitis pathogenesis. NEW & NOTEWORTHY Pancreatic fibrosis is a major concern for the successful treatment of chronic pancreatitis and pancreatic cancer. Therefore, restriction in the progression of fibrosis is the promising approach to manage the pancreatitis pathogenesis. Herein, we present in vivo evidences that pharmacological treatment of recombinant interleukin-15 improves remodeling and fibrosis in cerulein-induced chronic pancreatitis in mice. Our observations indicate that interleukin-15 immunotherapy may be a possible and potential strategy for restricting the progression of fibrosis in chronic pancreatitis.

Intestinal overexpression of interleukin (IL)-15 promotes tissue eosinophilia and goblet cell hyperplasia.

Interleukin (IL)-15 overexpression in eosinophilic gastrointestinal disorders is reported, but IL-15's role in promoting eosinophilic gastroenteritis is largely unknown. Therefore, we generated enterocyte-overexpressed IL-15 transgenic mice using Fabpi promoter. The Fabpi-IL-15 (iIL-15) transgenic mice showed induced IL-15 levels in the jejunum with a marked increase in jejunum eosinophils. However, no induction of eosinophilia in the blood or any other gastrointestinal segment was observed. Eosinophilia in the jejunum villus was substantially higher in iIL-15 mice compared to wild-type mice. In addition, goblet cell hyperplasia was also observed in the jejunum of iIL-15 mice. Furthermore, a significant correlation between induced IL-15 transcript and the IL-18 transcripts was observed. Therefore, to further understand the role of IL-18 in IL-15 mice associated gastrointestinal disorders, we generated iIL-15/IL-18Rα-/- mice. Using these mice, we found that IL-18 has an important role in promoting IL-15-induced eosinophilia. As intestinal IL-15 overexpression is reported in food intolerance, we examined OVA intolerance in iIL-15 mice. The OVA-sensitized and challenged iIL-15 mice experienced weight loss, diarrhea and eosinophilia in the jejunum. Taken together, our findings demonstrate that intestinal IL-15 overexpression induces IL-18-dependent eosinophilia and immunoglobulins in the intestine that promotes food allergic responses.

Activation of Plant Innate Immunity by Extracellular High Mobility Group Box 3 and Its Inhibition by Salicylic Acid.

Damage-associated molecular pattern molecules (DAMPs) signal the presence of tissue damage to induce immune responses in plants and animals. Here, we report that High Mobility Group Box 3 (HMGB3) is a novel plant DAMP. Extracellular HMGB3, through receptor-like kinases BAK1 and BKK1, induced hallmark innate immune responses, including i) MAPK activation, ii) defense-related gene expression, iii) callose deposition, and iv) enhanced resistance to Botrytis cinerea. Infection by necrotrophic B. cinerea released HMGB3 into the extracellular space (apoplast). Silencing HMGBs enhanced susceptibility to B. cinerea, while HMGB3 injection into apoplast restored resistance. Like its human counterpart, HMGB3 binds salicylic acid (SA), which results in inhibition of its DAMP activity. An SA-binding site mutant of HMGB3 retained its DAMP activity, which was no longer inhibited by SA, consistent with its reduced SA-binding activity. These results provide cross-kingdom evidence that HMGB proteins function as DAMPs and that SA is their conserved inhibitor.

Plant and Human MORC Proteins Have DNA-Modifying Activities Similar to Type II Topoisomerases, but Require One or More Additional Factors for Full Activity.

To elucidate one or more mechanisms through which microrchidia (MORC) proteins impact immunity, epigenetic gene silencing, and DNA modifications, the enzymatic activities of plant MORCs were characterized. Previously, we showed that plant MORC1s have ATPase and DNA endonuclease activities. Here, we demonstrate that plant MORCs have topoisomerase type II (topo II)-like activities, as they i) covalently bind DNA, ii) exhibit DNA-stimulated ATPase activity, iii) relax or nick supercoiled DNA, iv) catenate DNA, and v) decatenante kinetoplast DNA. Mutational analysis of tomato SlMORC1 suggests that a K loop-like sequence is required to couple DNA binding to ATPase stimulation as well as for efficient SlMORC1's DNA relaxation and catenation activities and in planta suppression of INF1-induced cell death, which is related to immunity. Human MORCs were found to exhibit the same topo II-like DNA modification activities as their plant counterparts. In contrast to typical topo IIs, SlMORC1 appears to require one or more accessory factors to complete some of its enzymatic activities, since addition of tomato extracts were needed for ATP-dependent, efficient conversion of supercoiled DNA to nicked/relaxed DNA and catenanes and for formation of topoisomer intermediates. Both plant and human MORCs bind salicylic acid; this suppresses their decatenation but not relaxation activity.

Heterodimerization of Arabidopsis calcium/proton exchangers contributes to regulation of guard cell dynamics and plant defense responses.

Arabidopsis thaliana cation exchangers (CAX1 and CAX3) are closely related tonoplast-localized calcium/proton (Ca2+/H+) antiporters that contribute to cellular Ca2+ homeostasis. CAX1 and CAX3 were previously shown to interact in yeast; however, the function of this complex in plants has remained elusive. Here, we demonstrate that expression of CAX1 and CAX3 occurs in guard cells. Additionally, CAX1 and CAX3 are co-expressed in mesophyll tissue in response to wounding or flg22 treatment, due to the induction of CAX3 expression. Having shown that the transporters can be co-expressed in the same cells, we demonstrate that CAX1 and CAX3 can form homomeric and heteromeric complexes in plants. Consistent with the formation of a functional CAX1-CAX3 complex, CAX1 and CAX3 integrated into the yeast genome suppressed a Ca2+-hypersensitive phenotype of mutants defective in vacuolar Ca2+ transport, and demonstrated enzyme kinetics different from those of either CAX protein expressed by itself. We demonstrate that the interactions between CAX proteins contribute to the functioning of stomata, because stomata were more closed in cax1-1, cax3-1, and cax1-1/cax3-1 loss-of-function mutants due to an inability to buffer Ca2+ effectively. We hypothesize that the formation of CAX1-CAX3 complexes may occur in the mesophyll to affect intracellular Ca2+ signaling during defense responses.

Food-Induced Acute Pancreatitis.

Food allergy, a commonly increasing problem worldwide, defined as an adverse immune response to food. A variety of immune-related effector cells such as mast cells, eosinophils, neutrophils, and T cells are involved in food-related allergic responses categorized as IgE mediated, non-IgE mediated, and mixed (IgE and non-IgE) depending upon underlying immunological mechanisms. The dietary antigens mainly target the gastrointestinal tract including pancreas that gets inflamed due to food allergy and leads acute pancreatitis. Reports indicate several food proteins induce pancreatitis; however, detailed underlying mechanism of food-induced pancreatitis is unexplored. The aim of the review is to understand and update the current scenario of food-induced pancreatitis. A comprehensive literature search of relevant research articles has been performed through PubMed, and articles were chosen based on their relevance to food allergen-mediated pancreatitis. Several cases in the literature indicate that acute pancreatitis has been provoked after the consumption of mustard, milk, egg, banana, fish, and kiwi fruits. Food-induced pancreatitis is an ignored and unexplored area of research. The review highlights the significance of food in the development of pancreatitis and draws the attention of physicians and scientists to consider food allergies as a possible cause for initiation of pancreatitis pathogenesis.

Bivalent Approach for Homodimeric Estradiol Based Ligand: Synthesis and Evaluation for Targeted Theranosis of ER(+) Breast Carcinomas.

The synthesis of estradiol based bivalent ligand [(EST)2DT] is reported and its potential for targeted imaging and therapy of ER(+) tumors has been evaluated. For the purpose, ethinylestradiol was functionalized with an azidoethylamine moiety via click chemistry. The resultant derivative was reacted in a bivalent mode with DTPA-dianhydride to form the multicoordinate chelating agent, (EST)2DT which displayed capability to bind (99m)Tc. The radiolabeled complex, (99m)Tc-(EST)2DT was obtained in >99% radiochemical purity and 20-48 GBq/µmol of specific activity. RBA assay revealed ∼15% binding with estrogen receptor. Evaluation of ligand on ER(+)-cell line (MCF-7) suggested enhanced and ER-mediated uptake. In vivo assays displayed early tracer accumulation in MCF-7 xenografts with tumor to muscle ratio ∼6 in 2 h and negligible uptakes in nontargeted organs. MTT assay performed on ER(+) and ER(-) cell lines displayed selective inhibition of ER(+) cancer cell growth with IC50 = 14.3 µM which was comparable to tamoxifen. The anticancer activity of the ligand is possibly due to the increase in ERß and suppression of ERα protein levels in gene transcription. The studies reveal the potential of (EST)2DT as diagnostic imaging agent with the additional benefits in therapy.

The GHKL ATPase MORC1 Modulates Species-Specific Plant Immunity in Solanaceae.

The microrchidia (MORC) proteins, a subset of the GHKL ATPase superfamily, were recently described as components involved in transcriptional gene silencing and plant immunity in Arabidopsis. To assess the role of MORC1 during resistance to Phytophthora infestans in solanaceous species, we altered the expression of the corresponding MORC1 homologs in potato, tomato, and Nicotiana benthamiana. Basal resistance to P. infestans was compromised in StMORC1-silenced potato and enhanced in overexpressing lines, indicating that StMORC1 positively affects immunity. By contrast, silencing SlMORC1 expression in tomato or NbMORC1 expression in N. benthamiana enhanced basal resistance to this oomycete pathogen. In addition, silencing SlMORC1 further enhanced resistance conferred by two resistance genes in tomato. Transient expression of StMORC1 in N. benthamiana accelerated cell death induced by infestin1 (INF1), whereas SlMORC1 or NbMORC1 suppressed it. Domain-swapping and mutational analyses indicated that the C-terminal region dictates the species-specific effects of the solanaceous MORC1 proteins on INF1-induced cell death. This C-terminal region also was required for homodimerization and phosphorylation of recombinant StMORC1 and SlMORC1, and its transient expression induced spontaneous cell death in N. benthamiana. Thus, this C-terminal region likely plays important roles in both determining and modulating the biological activity of MORC1 proteins.

Aspirin's Active Metabolite Salicylic Acid Targets High Mobility Group Box 1 to Modulate Inflammatory Responses.

Salicylic acid (SA) and its derivatives have been used for millennia to reduce pain, fever and inflammation. In addition, prophylactic use of acetylsalicylic acid, commonly known as aspirin, reduces the risk of heart attack, stroke and certain cancers. Because aspirin is rapidly de-acetylated by esterases in human plasma, much of aspirin's bioactivity can be attributed to its primary metabolite, SA. Here we demonstrate that human high mobility group box 1 (HMGB1) is a novel SA-binding protein. SA-binding sites on HMGB1 were identified in the HMG-box domains by nuclear magnetic resonance (NMR) spectroscopic studies and confirmed by mutational analysis. Extracellular HMGB1 is a damage-associated molecular pattern molecule (DAMP), with multiple redox states. SA suppresses both the chemoattractant activity of fully reduced HMGB1 and the increased expression of proinflammatory cytokine genes and cyclooxygenase 2 (COX-2) induced by disulfide HMGB1. Natural and synthetic SA derivatives with greater potency for inhibition of HMGB1 were identified, providing proof-of-concept that new molecules with high efficacy against sterile inflammation are attainable. An HMGB1 protein mutated in one of the SA-binding sites identified by NMR chemical shift perturbation studies retained chemoattractant activity, but lost binding of and inhibition by SA and its derivatives, thereby firmly establishing that SA binding to HMGB1 directly suppresses its proinflammatory activities. Identification of HMGB1 as a pharmacological target of SA/aspirin provides new insights into the mechanisms of action of one of the world's longest and most used natural and synthetic drugs. It may also provide an explanation for the protective effects of low-dose aspirin usage.