Inflamed Peritoneum Research Articles

ACUTE RESPIRATORY FAILURE FROM HYPERMAGNESEMIA REQUIRING PROLONGED MECHANICAL VENTILATION

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Magnesium is a major intra-cellular divalent cation. It is essential for multiple metabolic and physiological processes. It plays a crucial role in enzymatic actions, electron transporters, and the synthesis of nucleic acids. CASE PRESENTATION: A 73-year-old Caucasian male patient with a past medical history of Hypertension, Diabetes Mellitus type two, chronic constipation and chronic lower back pain presented to emergency department with 2-day history of diffuse abdominal pain. Acute abdominal series failed to show significant abnormality other than constipation and hence he was given one dose of oral magnesium citrate, one dose of GI cocktail (contains Maalox) and a fleets enema on day one of hospital stay. Overnight patient had a near syncopal episode and worsening of his abdominal pain while having a bowel movement. He was noted to be hypotensive with blood pressure of 84/47 mmhg, heart rate 132 and with a lactic acidosis level of 8.3 mmol/l, hence an abdominopelvic CT was done and showed free air in abdomen (Figures 1 and 2). Patient was taken to emergent laparotomy and underwent pyloric ulcer perforation repair with omental patch.On post-operative day 1 he was noted to have flaccid paralysis including lack of deep tendon and brain stem refluxes. Due to concerns of anoxic brain injury, brain imaging was done with no acute findings. Ionized Calcium, Phosphate levels and Potassium levels were within normal limits. He was noted to have Magnesium level of 9.2 mg/dl. This was thought to be cause of his flaccid paralysis and hence was initiated on Intravenous fluids along with Lasix. In view of oliguric kidney injury, emergent Hemodialysis was initiated. Patient received two hemodialysis sessions with Magnesium levels returning to physiologic levels. Over the next 48-72 hours patient has significant improvement in his hypotension and bradycardia. His mentation and muscle strength and acute kidney injury also improved. He was successfully liberated from the ventilator and subsequently discharged to rehab DISCUSSION: Our patient had acute respiratory failure with failure to extubate due to flaccid paralysis of his respiratory muscles. This was found to be a result of extremely high serum magnesium levels which was unexpected given he received only two doses of magnesium containing agents (magnesium citrate and Maalox) within the last 2 weeks. Hypermagnesemia is most commonly seen in the setting of renal impairment along with concomitant excessive magnesium intake. Neuromuscular and cardiac toxicity are common complications of hypermagnesemia. [2] Our patient had all the features usually described in hypermagnesmia but with only a small intake of Magnesium in setting of acute kidney injury. We hypothesize that the pyloric perforation allowed for increased uptake of magnesium through the inflamed peritoneum CONCLUSIONS: N/A REFERENCE #1: Cascella, Marco, Sarosh Vaqar et al. "Hypermagnesemia." StatPearls, StatPearls Publishing, 2020. REFERENCE #2: Agus, Z. S., M. Morad et al. "Modulation of cardiac ion channels by magnesium." Annual review of physiology 53.1 (1991):299-307. REFERENCE #3: Lee, Jay Wook. "Fluid and electrolyte disturbances in critically ill patients." Electrolytes & Blood Pressure 8.2 (2010):72-81. DISCLOSURES: No relevant relationships by Khalid Sawalha, source=Web Response

CLEC-2 Prevents Accumulation and Retention of Inflammatory Macrophages During Murine Peritonitis.

Platelets play a key role in the development, progression and resolution of the inflammatory response during sterile inflammation and infection, although the mechanism is not well understood. Here we show that platelet CLEC-2 reduces tissue inflammation by regulating inflammatory macrophage activation and trafficking from the inflamed tissues. The immune regulatory function of CLEC-2 depends on the expression of its ligand, podoplanin, upregulated on inflammatory macrophages and is independent of platelet activation and secretion. Mechanistically, platelet CLEC-2 and also recombinant CLEC-2-Fc accelerates actin rearrangement and macrophage migration by increasing the expression of podoplanin and CD44, and their interaction with the ERM proteins. During ongoing inflammation, induced by lipopolysaccharide, treatment with rCLEC-2-Fc induces the rapid emigration of peritoneal inflammatory macrophages to mesenteric lymph nodes, thus reducing the accumulation of inflammatory macrophages in the inflamed peritoneum. This is associated with a significant decrease in pro-inflammatory cytokine, TNF-α and an increase in levels of immunosuppressive, IL-10 in the peritoneum. Increased podoplanin expression and actin remodelling favour macrophage migration towards CCL21, a soluble ligand for podoplanin and chemoattractant secreted by lymph node lymphatic endothelial cells. Macrophage efflux to draining lymph nodes induces T cell priming. In conclusion, we show that platelet CLEC-2 reduces the inflammatory phenotype of macrophages and their accumulation, leading to diminished tissue inflammation. These immunomodulatory functions of CLEC-2 are a novel strategy to reduce tissue inflammation and could be therapeutically exploited through rCLEC-2-Fc, to limit the progression to chronic inflammation.

The neutrotime transcriptional signature defines a single continuum of neutrophils across biological compartments

Neutrophils are implicated in multiple homeostatic and pathological processes, but whether functional diversity requires discrete neutrophil subsets is not known. Here, we apply single-cell RNA sequencing to neutrophils from normal and inflamed mouse tissues. Whereas conventional clustering yields multiple alternative organizational structures, diffusion mapping plus RNA velocity discloses a single developmental spectrum, ordered chronologically. Termed here neutrotime, this spectrum extends from immature pre-neutrophils, largely in bone marrow, to mature neutrophils predominantly in blood and spleen. The sharpest increments in neutrotime occur during the transitions from pre-neutrophils to immature neutrophils and from mature marrow neutrophils to those in blood. Human neutrophils exhibit a similar transcriptomic pattern. Neutrophils migrating into inflamed mouse lung, peritoneum and joint maintain the core mature neutrotime signature together with new transcriptional activity that varies with site and stimulus. Together, these data identify a single developmental spectrum as the dominant organizational theme of neutrophil heterogeneity.

In Vivo Functions of Mouse Neutrophils Derived from HoxB8-Transduced Conditionally Immortalized Myeloid Progenitors.

Although neutrophils play important roles in immunity and inflammation, their analysis is strongly hindered by their short-lived and terminally differentiated nature. Prior studies reported conditional immortalization of myeloid progenitors using retroviral expression of an estrogen-dependent fusion protein of the HoxB8 transcription factor. This approach allowed the long-term culture of mouse myeloid progenitors (HoxB8 progenitors) in estrogen-containing media, followed by differentiation toward neutrophils upon estrogen withdrawal. Although several reports confirmed the in vitro functional responsiveness of the resulting differentiated cells (HoxB8 neutrophils), little is known about their capacity to perform in vivo neutrophil functions. We have addressed this issue by an in vivo transplantation approach. In vitro-generated HoxB8 neutrophils showed a neutrophil-like phenotype and were able to perform conventional neutrophil functions, like respiratory burst, chemotaxis, and phagocytosis. The i.v. injection of HoxB8 progenitors into lethally irradiated recipients resulted in the appearance of circulating donor-derived HoxB8 neutrophils. In vivo-differentiated HoxB8 neutrophils were able to migrate to the inflamed peritoneum and to phagocytose heat-killed Candida particles. The reverse passive Arthus reaction could be induced in HoxB8 chimeras but not in irradiated, nontransplanted control animals. Repeated injection of HoxB8 progenitors also allowed us to maintain stable circulating HoxB8 neutrophil counts for several days. Injection of arthritogenic K/B×N serum triggered robust arthritis in HoxB8 chimeras, but not in irradiated, nontransplanted control mice. Taken together, our results indicate that HoxB8 progenitor-derived neutrophils are capable of performing various in vivo neutrophil functions, providing a framework for using the HoxB8 system for the in vivo analysis of neutrophil function.

Diet-induced dyslipidemia induces metabolic and migratory adaptations in regulatory T cells.

AimsA hallmark of advanced atherosclerosis is inadequate immunosuppression by regulatory T (Treg) cells inside atherosclerotic lesions. Dyslipidemia has been suggested to alter Treg cell migration by affecting the expression of specific membrane proteins, thereby decreasing Treg cell migration towards atherosclerotic lesions. Besides membrane proteins, cellular metabolism has been shown to be a crucial factor in Treg cell migration. We aimed to determine whether dyslipidemia contributes to altered migration of Treg cells, in part, by affecting cellular metabolism.Methods and resultsDyslipidemia was induced by feeding Ldlr−/− mice a western-type diet for 16–20 weeks and intrinsic changes in Treg cells affecting their migration and metabolism were examined. Dyslipidemia was associated with altered mTORC2 signalling in Treg cells, decreased expression of membrane proteins involved in migration, including CD62L, CCR7, and S1Pr1, and decreased Treg cell migration towards lymph nodes. Furthermore, we discovered that diet-induced dyslipidemia inhibited mTORC1 signalling, induced PPARδ activation and increased fatty acid (FA) oxidation in Treg cells. Moreover, mass-spectrometry analysis of serum from Ldlr−/− mice with normolipidemia or dyslipidemia showed increases in multiple PPARδ ligands during dyslipidemia. Treatment with a synthetic PPARδ agonist increased the migratory capacity of Treg cells in vitro and in vivo in an FA oxidation-dependent manner. Furthermore, diet-induced dyslipidemia actually enhanced Treg cell migration into the inflamed peritoneum and into atherosclerotic lesions in vitro.ConclusionAltogether, our findings implicate that dyslipidemia does not contribute to atherosclerosis by impairing Treg cell migration as dyslipidemia associated with an effector-like migratory phenotype in Treg cells.

A C-terminal fragment of adhesion protein Fibulin7 regulates neutrophil migration and functions and improves survival in LPS induced systemic inflammation

Accumulation of hyperactive neutrophils in the visceral organs was shown to be associated with sepsis-induced multi-organ failure. Recently, a C-terminal fragment of secreted glycoprotein Fibulin7 (Fbln7-C) was shown to inhibit angiogenesis and regulate monocyte functions in inflammatory conditions. However, its effects on neutrophil functions and systemic inflammation induced lethality remain unknown. In this study, we show that human peripheral blood neutrophils adhered to Fbln7-C in a dose-dependent manner via integrin β1. Moreover, the presence of Fbln7-C inhibited spreading, and fMLP mediated random migration of neutrophils on fibronectin. Significant reduction in ROS and inflammatory cytokine production (i.e., IL-6, IL-1β) was observed, including a reduction in ERK1⁄2 phosphorylation in neutrophils stimulated with LPS and fMLP in the presence of Fbln7-C compared to untreated controls. In an in vivo model of endotoxemia, the administration of Fbln7-C (10 μg/dose) significantly improved survival and reduced the infiltration of neutrophils to the site of inflammation. Additionally, neutrophils infiltrating into the inflamed peritoneum of Fbln7-C administered animals expressed lower levels CD11b marker, IL-6, and produced lower levels of ROS upon stimulation with PMA compared to untreated controls. In conclusion, our results show that Fbln7-C could bind to the integrin β1 on the neutrophil surface and regulate their inflammatory functions.

Context-Dependent Role of Vinculin in Neutrophil Adhesion, Motility and Trafficking

Neutrophils are innate immune effector cells that traffic from the circulation to extravascular sites of inflammation. β2 integrins are important mediators of the processes involved in neutrophil recruitment. Although neutrophils express the cytoskeletal protein vinculin, they do not form mature focal adhesions. Here, we characterize the role of vinculin in β2 integrin-dependent neutrophil adhesion, migration, mechanosensing, and recruitment. We observe that knockout of vinculin attenuates, but does not completely abrogate, neutrophil adhesion, spreading, and crawling under static conditions. However, we also found that vinculin deficiency does not affect these behaviors in the presence of forces from fluid flow. In addition, we identify a role for vinculin in mechanosensing, as vinculin-deficient neutrophils exhibit attenuated spreading on stiff, but not soft, substrates. Consistent with these findings, we observe that in vivo neutrophil recruitment into the inflamed peritoneum of mice remains intact in the absence of vinculin. Together, these data suggest that while vinculin regulates some aspects of neutrophil adhesion and spreading, it may be dispensable for β2 integrin-dependent neutrophil recruitment in vivo.

Possible Role of the Posterior Compartment Peritonectomy, as a Part of the Complex Surgery, Regarding Recurrence Rate, Improvement of Symptoms and Fertility Rate in Patients with Endometriosis, Long-Term Follow-Up

Beside the pain, there are 2 further problems in the management of endometriosis: the high recurrence rate (10% per year) and the high rate of impaired fertility.The objective of this study was to investigate the pathogenesis of these 2 factors. This is a retrospective cohort study, and the aim is to evaluate the complete excision of endometriotic lesions, including the posterior compartment of the peritoneum, with regard to postoperative outcome, focusing on relieving pain, increasing fertility rate, and decreasing recurrence rate. Charité-University Clinic, Department of Gynaecology, Endometriosis research Centre. Fifty-four patients were enrolled in this study, with severe deep infiltrating endometriosis (scored by ENZIAN) and superficial endometriosis, as well as endometriomas (revised American Society for Reproductive Medicine [rASRM] I = 3; II = 15; III = 10; and IV = 26). Posterior compartment peritonectomy (visible endometriotic lesions and inflamed altered peritoneum) was performed in all patients as part of a complex surgery: complete excision of endometriosis. Postoperative outcomes were evaluated, based on the postoperative follow-up (up to 5 years) of 54 investigated patients. In 36 women (66%) preoperative complaints were eliminated. Furthermore, of 28 women seeking improved fertility, pregnancy was reported in 13 cases (46%). In 7 (54%) cases pregnancy occurred spontaneously, and in the remainder with assisted fertilization. In addition, long-term follow-up demonstrated a recurrence rate in 1.8% of patients. Overall, the number of complaints was significantly reduced. Only in the case of reproductive-aged women with ongoing postoperative complaints was it important to preserve the uterus. Although this pilot study on systematic posterior peritonectomy showed improvement in recurrence and fertility rate, the main question remains: will this surgical technique achieve better results and outcomes in the future? This has to be addressed in a prospective randomized study.

Omega-3 polyunsaturated fatty acids impinge on CD4+ T cell motility and adipose tissue distribution via direct and lipid mediator-dependent effects.

Adaptive immunity contributes to the pathogenesis of cardiovascular metabolic disorders (CVMD). The omega-3 polyunsaturated fatty acids (n-3PUFA) are beneficial for cardiovascular health, with potential to improve the dysregulated adaptive immune responses associated with metabolic imbalance. We aimed to explore the mechanisms through which n-3PUFA may alter T cell motility and tissue distribution to promote a less inflammatory environment and improve lymphocyte function in CVMD. Using mass spectrometry lipidomics, cellular, biochemical, and in vivo and ex vivo analyses, we investigated how eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the main n-3PUFA, modify the trafficking patterns of activated CD4+ T cells. In mice subjected to allogeneic immunization, a 3-week n-3PUFA-enriched diet reduced the number of effector memory CD4+ T cells found in adipose tissue, and changed the profiles of eicosanoids, octadecanoids, docosanoids, endocannabinoids, 2-monoacylglycerols, N-acyl ethanolamines, and ceramides, in plasma, lymphoid organs, and fat tissues. These bioactive lipids exhibited differing chemotactic properties when tested in chemotaxis assays with activated CD4+ T cells in vitro. Furthermore, CD4+ T cells treated with EPA and DHA showed a significant reduction in chemokinesis, as assessed by trans-endothelial migration assays, and, when implanted in recipient mice, demonstrated less efficient migration to the inflamed peritoneum. Finally, EPA and DHA treatments reduced the number of polarized CD4+ T cells in vitro, altered the phospholipid composition of membrane microdomains and decreased the activity of small Rho GTPases, Rhoα, and Rac1 instrumental in cytoskeletal dynamics. Our findings suggest that EPA and DHA affect the motility of CD4+ T cells and modify their ability to reach target tissues by interfering with the cytoskeletal rearrangements required for cell migration. This can explain, at least in part, the anti-inflammatory effects of n-3PUFA supporting their potential use in interventions aiming to address adipocyte low-grade inflammation associated with cardiovascular metabolic disease.

Streptococcus pneumoniae primary peritonitis mimicking acute appendicitis in an immunocompetent patient: a case report and review of the literature

IntroductionPrimary peritonitis without an identifiable intra-abdominal source is extremely rare in healthy individuals; it is commonly seen in cases of nephrotic syndrome, cirrhosis and end-stage liver disease, ascites, immunosuppression, and inflamed peritoneum due to pre-existing autoimmune and oncological conditions.Case presentationWe present the case of a 68-year-old Caucasian woman operated on due to acute abdomen with a provisional diagnosis of acute appendicitis. During the operation a small amount of free intra-abdominal fluid was found. Her uterus, ovaries, and fallopian tubes were macroscopically normal. Therefore, with the suspicion of appendicitis, appendectomy was performed. Her blood cultures were negative while peritoneal fluid was positive for capsulated form of Streptococcus pneumoniae. A 30-day follow-up was performed and she was asymptomatic without any sign of infection.DiscussionStreptococcus pneumoniae commonly causes upper respiratory tract infection and cutaneous infections. It very rarely causes gastrointestinal infection and it is very rarely responsible for primary peritonitis and septic shock syndrome.ConclusionPneumococcal peritonitis has a rare occurrence and represents a clinical challenge because of its subtle and non-specific clinical findings. The interest in our case lays in the relatively rare diagnosis of primary peritonitis mimicking acute appendicitis.

Exogenous glutamine impairs neutrophils migration into infections sites elicited by lipopolysaccharide by a multistep mechanism.

Glutamine (GLN) is the most abundant free amino acid in the body, and is considered as a conditionally essential amino acid under stress conditions, acting as an important modulator of the immune response. We here investigated the role of exogenous GLN treatment on leukocyte migration after the onset of endotoxemia and the intracellular mechanisms of GLN actions on neutrophils. Two in vivo models of endotoxemia caused by lipopolysaccharide of Escherichia coli (LPS) injection were carried out in male outbred Balb/C mice 2-3months old, as follow: (1) LPS (50μg/kg) was intravenously injected 1h prior to intravenous injection of GLN (0.75mg/kg) and samples were collected 2h later to investigate the role of GLN on the acute lung inflammation; (2) LPS (1mg/kg) was intraperitoneally injected 1h prior to intravenous injection of GLN (0.75mg/kg) and samples were collected 18h later to measure the effects of GLN on local and later phases of inflammation in the peritoneum. Results showed that GLN administration reduced the number of neutrophils in the inflamed lungs, partially recovery of the reduced number of leukocytes in the blood; reduced adhesion molecules on lung endothelium and on circulating neutrophils. Moreover, GLN treatment diminished the number of neutrophils, levels of chemotactic cytokine CXCL2 in the inflamed peritoneum, and neutrophils collected from the peritoneum of GLN-treated mice presented lower levels of Rho, Rac, and JNK. Together, our data show novel mechanisms involved in the actions of GLN on neutrophils migration.

Engulfment of Hb-activated platelets differentiates monocytes into pro-inflammatory macrophages in PNH patients.

The distinct response shown by different phenotypes of macrophages and monocytes under various clinical conditions has put the heterogeneity of these cells into focus of investigation for several diseases. Recently, we have described that after engulfing hemoglobin (Hb)-activated platelets, classical monocytes differentiated into pro-inflammatory phenotypes, which were abundant in the circulation of paroxysmal nocturnal hemoglobinuria (PNH) and sickle cell disease patients. Our current study shows that upon engulfment of Hb-activated platelets, monocytes differentiate into M1-macrophages under M1-polarization stimulus (GM-CSF, IFN-γ + LPS). When grown under M2-polarization stimulus (M-CSF, IL-4 + IL13), the cells exhibited an M1-like phenotype, secreted elevated levels of pro-inflammatory cytokines including TNF-α and IL-1β, and displayed loss of the secretion of cytokine such as IL-10 and also phagocytic ability unlike the conventional M2 macrophages. Interestingly, when differentiated under the above polarization stimulus, monocytes from PNH patients expressed high levels of CD80 and phospho-STAT1, like M1 macrophages. Hemolytic mice also exhibited a gradual increase in monocyte-platelet aggregates in circulation and accumulation of CD80high macrophages in thioglycollate-induced inflamed peritoneum. The spleen of the mice was also populated by CD80high macrophages with compromised phagocytic capacity. Our findings suggest that the hemolytic environment and specifically the Hb-activated platelets, which are abundant in circulation during intravascular hemolysis, closely regulate monocyte differentiation.

Abstract 493: Neutrophil and Macrophage Cell Surface Colony-Stimulating Factor-1 is Shed by a Disintegrin and Metalloprotease 17 and Contributes to Stimulating Macrophage Proliferation in Inflammation

Recent studies highlight a role for macrophage proliferation post monocyte recruitment in inflammatory conditions, such as atherosclerosis. However, the mechanisms regulating macrophage proliferation are not well understood. Using an acute peritonitis model, we identified a 40 ± 8% reduction (mean ± SEM; n=5; p<0.01) in macrophages in the S phase of the cell cycle 40 hrs post thioglycollate injection in mice lacking the transmembrane protease ADAM17 in hematopoietic cells. ADAM17 is a member of a disintegrin and metalloprotease family that cleaves many cell surface proteins involved in inflammation. The macrophage proliferation defect in ADAM17 null chimeras was associated with a 60 ± 10% (n=5; p<0.001) decrease in soluble macrophage colony-stimulating factor (CSF)-1 in the peritoneum, and was rescued by intraperitoneal injection of CSF-1. We demonstrate that neutrophils, the first innate immune cell that migrates into inflammatory sites, and macrophages are both major sources of cell surface (cs)CSF-1 in this acute inflammation model, adding to the current knowledge that stromal, epithelial and endothelial cells are sources of CSF-1. We show that ADAM17 is critical in mediating csCSF-1 release in the inflamed peritoneum, and that this release following neutrophil extravasation is associated with elevated expression of iRhom2, a member of the rhomboid-like superfamily, which promotes ADAM17 maturation and trafficking to the cell surface. Accordingly, deletion of hematopoietic iRhom2 is sufficient to prevent csCSF-1 release from neutrophils and macrophages, thus recapitulating the defect in macrophage proliferation seen in ADAM17 null cells. Our data indicate that csCSF-1 release and macrophage proliferation is self-limiting in states of acute inflammation due to the transient nature of leukocyte recruitment and temporally restricted csCSF-1 expression and release. In chronic inflammation such as atherosclerosis, we show that macrophage proliferation is decreased by 30 ± 7% (n=6; p<0.01) in atherosclerotic lesions of ADAM17 hematopoietic null LDL receptor-deficient mice fed a high fat diet for 16 weeks. Together, these results demonstrate a novel mechanism governing macrophage proliferation in both acute and chronic inflammation.

Cell adhesion protein fibulin-7 and its C-terminal fragment negatively regulate monocyte and macrophage migration and functions in vitro and in vivo.

Fibulin-7 (Fbln7) has been identified as the latest member of the fibulin family of secreted glycoproteins in developing teeth, functioning as a cell adhesion molecule and interacting with other matrix proteins, receptors, and growth factors. More recently, we have shown that the C-terminal Fbln7 fragment (Fbln7-C) has antiangiogenic activity in vitro. Fbln7 is also expressed in immune-privileged tissues, such as eye and placenta, but its functional significance is unknown. In the current study, we show that human monocytes adhere to both full-length Fbln7 (Fbln7-FL) and Fbln7-C, in part, via integrins α5β1 and α2β1. Morphologic studies and surface expression analyses of CD14, mannose receptor (CD206), major histocompatibility complex II, and CD11b receptors revealed that both Fbln7-FL and Fbln7-C inhibit M-CSF-induced monocyte differentiation. Fbln7-C had significantly greater negative effects on cell spreading and stress fiber formation, including the production of IL-6 and metalloproteinase-1/-9 compared with Fbln7-FL. Furthermore, in an LPS-induced systemic inflammation model, Fbln7-C and Fbln7-FL reduced the infiltration of immune cells, such as neutrophils and macrophages, to the inflamed peritoneum. Thus, these results suggest that Fbln7 and Fbln7-C could modulate the activity of immune cells and have therapeutic potential for inflammatory diseases.-Sarangi, P. P., Chakraborty, P., Dash, S. P., Ikeuchi, T., de Vega, S., Ambatipudi, K., Wahl, L., Yamada, Y. Cell adhesion protein fibulin-7 and its C-terminal fragment negatively regulate monocyte and macrophage migration and functions in vitro and in vivo.

Boerhaave syndrome in emergency abdominal surgery

Aim. To present a case of spontaneous rupture of esophagus taking into account its rarity, diversity of clinical manifestations, complexity of making a diagnosis and treatment of this disease.Methods. Over the past three years in Kazan City Clinical Hospital №7 three cases of the esophageal damage were registered. The age of the patients ranged from 48 to 67 years, including 2 females and 1 male with spontaneous rupture of esophagus.Results. A 48-year old patient was admitted to the hospital complaining of vomiting with blood followed by appearance of retrosternal pain which appeared immediately after the holiday and nutritional stress. Emergency fibrogastroduodenoscopy (FEGDS) was performed. Endoscopy revealed signs suggestive of diaphragmatic hernia, and 2 ruptures of esophageal mucous membrane up to 3 cm on the left wall of esophagus above the cardiac sphincter. The diagnosis of Mallory-Weiss syndrome complicated with bleeding was made. Surgery: laparotomy, abdominal revision. The abdominal cavity had dark hemorrhagic discharge, inflamed peritoneum and signs of diffuse peritonitis. Diaphragmatic crurotomy was performed. Revision of abdominal esophagus revealed two longitudinal ruptures of the left esophageal wall 1.5 and 3 cm long 8 cm up from the cardiac sphincter. The ruptures were sutured by discontinuous atraumatic encircling stitch. Lower mediastinum was drained with two double-lumen tubes, the gastric probe was installed through the nose. During the follow up CT scan and ultrasound of thoracic cavity were performed. Liquid nutrition through the probe lasted up to 20 days. The mediastinum was lavaged through double-lumen tube with an aqueous solution of chlorhexidine and chymotrypsin up to 32 days. The patient was discharged on day 34 in a satisfactory condition.Conclusion. One of the etiologic factors of spontaneous esophageal rupture may be diaphragmatic hernia of the esophagus with increased intraesophageal pressure; early surgical intervention, suturing of esophageal rupture, mediastinal drainage and lavage in the postoperative period are fundamental steps in the treatment of esophageal rupture.

Galectin-3-null mice display defective neutrophil clearance during acute inflammation.

Galectin-3 has been associated with a plethora of proinflammatory functions because of its ability, among others, to promote neutrophil activation and because of the reduction in neutrophil recruitment in models of infection in Gal-3-null mice. Conversely, it has also been linked to resolution of inflammation through its actions as an opsonin and its ability to promote efferocytosis of apoptotic neutrophils. Using a self-resolving model of peritonitis, we have addressed the modulation and role of Gal-3 in acute inflammation. We have shown that Gal-3 expression is increased in neutrophils that travel to the inflamed peritoneum and that cellular localization of this lectin is modulated during the course of the inflammatory response. Furthermore, neutrophil recruitment to the inflamed peritoneum is increased in Gal-3-null mice during the course of the response, and that correlates with reduced numbers of monocytes/macrophages in the cavities of those mice, as well as reduced apoptosis and efferocytosis of Gal-3-null neutrophils. These data indicate a role for endogenous Gal-3 in neutrophil clearance during acute inflammation.

The Role of Integrins αMβ2 (Mac-1, CD11b/CD18) and αDβ2 (CD11d/CD18) in Macrophage Fusion

The subfamily of β2 integrins is implicated in macrophage fusion, a hallmark of chronic inflammation. Among β2 family members, integrin Mac-1 (αMβ2, CD11b/CD18) is abundantly expressed on monocyte/macrophages and mediates critical adhesive reactions of these cells. However, the role of Mac-1 in macrophage fusion leading to the formation of multinucleated giant cells remains unclear. Moreover, the role of integrin αDβ2 (CD11d/CD18), a receptor with recognition specificity overlapping that of Mac-1, is unknown. We found that multinucleated giant cells are formed in the inflamed mouse peritoneum during the resolution phase of inflammation, and their numbers were approximately twofold higher in wild-type mice than in Mac-1(-/-) mice. Analyses of isolated inflammatory peritoneal macrophages showed that IL-4-induced fusion of Mac-1-deficient cells was strongly reduced compared with wild-type counterparts. The examination of adhesive reactions known to be required for fusion showed that spreading, but not adhesion and migration, was reduced in Mac-1-deficient macrophages. Fusion of αDβ2-deficient macrophages was also significantly decreased, albeit to a smaller degree. Deficiency of intercellular adhesion molecule 1, a counter-receptor for Mac-1 and αDβ2, did not alter the fusion rate. The results indicate that both Mac-1 and αDβ2 support macrophage fusion with Mac-1 playing a dominant role and suggest that Mac-1 may mediate cell-cell interactions with a previously unrecognized counter-receptor(s).

Heparanase of murine effector lymphocytes and neutrophils is not required for their diapedesis into sites of inflammation

Heparanase, the exclusive mammalian heparan sulfate-degrading enzyme, has been suggested to be utilized by leukocytes to penetrate through the dense basement membranes surrounding blood venules. Despite its established role in tumor cell invasion, heparanase function in leukocyte extravasation has never been demonstrated. We found that TH1/TC1-type effector T cells are highly enriched for this enzyme, with a 3.6-fold higher heparanase mRNA expression compared with naive lymphocytes. Using adoptive transfer of wild-type and heparanase-deficient effector T cells into inflamed mice, we show that T-cell heparanase was not required for extravasation inside inflamed lymph nodes or skin. Leukocyte extravasation through acute inflamed skin vessels was also heparanase independent. Furthermore, neutrophils emigrated to the inflamed peritoneal cavity independently of heparanase expression on either the leukocytes or on the endothelial and mesothelial barriers, and overexpression of the enzyme on neutrophils did not facilitate their emigration. However, heparanase absence significantly reduced monocyte emigration into the inflamed peritoneal cavity. These results collectively suggest that neither leukocyte nor endothelial heparanase is required for T-cell and neutrophil extravasation through inflamed vascular barriers, whereas this enzyme is required for optimal monocyte recruitment to inflamed peritoneum.

Increased neutralization capacity of TNF alpha in sera of MS patients may play a role in — MS pathogenesis and is reversed by therapy with interferon-γ

in vivo analysis. Lymphocyte migration in vitro was evaluated in transwell assays using CD4 T cells purified from anti-muCD52-treated mice. In vivo migration was assessed using an acute CNS inflammation model in which mice were injected intracerebroventricularly with lipopolysaccharide (LPS) following anti-muCD52 treatment. Similarly, migration of innate immune cell subsets was evaluated in a peritonitis model of inflammation, in which animals were injected intraperitoneally with thioglycollate 3 days following anti-muCD52 treatment. The numbers of CNS-infiltrating lymphocytes or peritoneum-infiltrating cells were measured by polychromatic flow cytometry. Results: Immune cells from anti-muCD52-treated mice retained their ability to migrate. In vitro, CD4 T cells were able to migrate in response to SDF-1alpha as efficiently as cells from vehicle-treated animals. In vivo, lymphocytes in anti-muCD52-treated animals were able to migrate into the CNS following local induction of inflammation by LPS. Similarly, innate immune cell migration was not affected by anti-muCD52 treatment, as similar numbers and types of cells were observed in the inflamed peritoneum of anti-muCD52and vehicle-treated animals. Conclusions: These results indicate that following anti-CD52 treatment, immune cells retain their ability to migrate. These findings suggest that anti-CD52 treatment may not compromise immune surveillance, but further studies are required. Study Supported by: Genzyme, a Sanofi company.

Tyrosine Phosphorylation of CD13 Regulates Inflammatory Cell–Cell Adhesion and Monocyte Trafficking

CD13 is a large cell surface peptidase expressed on the monocytes and activated endothelial cells that is important for homing to and resolving the damaged tissue at sites of injury. We showed previously that cross-linking of human monocytic CD13 with activating Abs induces strong adhesion to endothelial cells in a tyrosine kinase- and microtubule-dependent manner. In the current study, we examined the molecular mechanisms underlying these observations in vitro and in vivo. We found that cross-linking of CD13 on U937 monocytic cells induced phosphorylation of a number of proteins, including Src, FAK, and ERK, and inhibition of these abrogated CD13-dependent adhesion. We found that CD13 itself was phosphorylated in a Src-dependent manner, which was an unexpected finding because its 7-aa cytoplasmic tail was assumed to be inert. Furthermore, CD13 was constitutively associated with the scaffolding protein IQGAP1, and CD13 cross-linking induced complex formation with the actin-binding protein α-actinin, linking membrane-bound CD13 to the cytoskeleton, further supporting CD13 as an inflammatory adhesion molecule. Mechanistically, mutation of the conserved CD13 cytoplasmic tyrosine to phenylalanine abrogated adhesion; Src, FAK, and ERK phosphorylation; and cytoskeletal alterations upon Ab cross-linking. Finally, CD13 was phosphorylated in isolated murine inflammatory peritoneal exudate cells, and adoptive transfer of monocytic cell lines engineered to express the mutant CD13 were severely impaired in their ability to migrate into the inflamed peritoneum, confirming that CD13 phosphorylation is relevant to inflammatory cell trafficking in vivo. Therefore, this study identifies CD13 as a novel, direct activator of intracellular signaling pathways in pathophysiological conditions.