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Vascular pathologies show locational predisposition throughout the body; further insights into the transcriptomics basis of this vascular heterogeneity are needed. We analyzed transcriptomes from cultured endothelial cells and vascular smooth muscle cells from nine adult canine macrovessels: the aorta, coronary artery, vena cava, portal vein, femoral artery, femoral vein, saphenous vein, pulmonary vein, and pulmonary artery. We observed that organ-specific expression patterns persist in vitro, indicating that these genes are not regulated by blood flow or surrounding cell types but are likely fixed in the epigenetic memory. We further demonstrated the preserved location-specific expression of GATA4 protein in cultured cells and in the primary adult vessel. On a functional level, arterial and venous endothelial cells differed in vascular network morphology as the arterial networks maintained a higher complexity. Our findings prompt the rethinking of the extrapolation of results from single-origin endothelial cell systems.

Our understanding of the interplay between human adipose tissue and the immune system is limited. The mesothelium, an immunologically active structure, emerged as a source of visceral adipose tissue. After investigating the mesothelial properties of human visceral and subcutaneous adipose tissue and their progenitors, we explored whether the dysfunctional obese and Crohn's disease environments influence the mesothelial/mesenchymal properties of their adipocyte precursors, as well as their ability to mount an immune response. Using a tandem transcriptomic/proteomic approach, we evaluated the mesothelial and mesenchymal expression profiles in adipose tissue, both in subjects covering a wide range of body-mass indexes and in Crohn's disease patients. We also isolated adipose tissue precursors (adipose-derived stem cells, ASCs) to assess their mesothelial/mesenchymal properties, as well as their antigen-presenting features. Human visceral tissue presented a mesothelial phenotype not detected in the subcutaneous fat. Only ASCs from mesenteric adipose tissue, named creeping fat, had a significantly higher expression of the hallmark mesothelial genes mesothelin (MSLN) and Wilms' tumor suppressor gene 1 (WT1), supporting a mesothelial nature of these cells. Both lean and Crohn's disease visceral ASCs expressed equivalent surface percentages of the antigen-presenting molecules human leucocyte antigen-DR isotype (HLA-DR) and CD86. However, lean-derived ASCs were predominantly HLA-DR dim, whereas in Crohn's disease, the HLA-DR bright subpopulation was increased 3.2-fold. Importantly, the mesothelial-enriched Crohn's disease precursors activated CD4 + T-lymphocytes. Our study evidences a mesothelial signature in the creeping fat of Crohn's disease patients and its progenitor cells, the latter being able to present antigens and orchestrate an immune response

Our understanding of the interplay between human adipose tissue and the immune system is limited. The mesothelium, an immunologically active structure, emerged as a source of visceral adipose tissue. After investigating the mesothelial properties of human visceral and subcutaneous adipose tissue and their progenitors, we explored whether the dysfunctional obese and Crohn's disease environments influence the mesothelial/mesenchymal properties of their adipocyte precursors, as well as their ability to mount an immune response. Using a tandem transcriptomic/proteomic approach, we evaluated the mesothelial and mesenchymal expression profiles in adipose tissue, both in subjects covering a wide range of body-mass indexes and in Crohn's disease patients. We also isolated adipose tissue precursors (adipose-derived stem cells, ASCs) to assess their mesothelial/mesenchymal properties, as well as their antigen-presenting features. Human visceral tissue presented a mesothelial phenotype not detected in the subcutaneous fat. Only ASCs from mesenteric adipose tissue, named creeping fat, had a significantly higher expression of the hallmark mesothelial genes mesothelin (MSLN) and Wilms' tumor suppressor gene 1 (WT1), supporting a mesothelial nature of these cells. Both lean and Crohn's disease visceral ASCs expressed equivalent surface percentages of the antigen-presenting molecules human leucocyte antigen-DR isotype (HLA-DR) and CD86. However, lean-derived ASCs were predominantly HLA-DR (dim), whereas in Crohn's disease, the HLA-DR (bright) subpopulation was increased 3.2-fold. Importantly, the mesothelial-enriched Crohn's disease precursors activated CD4(+) T-lymphocytes. Our study evidences a mesothelial signature in the creeping fat of Crohn's disease patients and its progenitor c

Essentially all Staphylococcus aureus (S. aureus) bacteria that gain access to the circulation are plucked out of the bloodstream by the intravascular macrophages of the liver - the Kupffer cells. It is also thought that these bacteria are disseminated via the bloodstream to other organs. Our data show that S. aureus inside Kupffer cells grew and escaped across the mesothelium into the peritoneal cavity and immediately infected GATA-binding factor 6-positive (GATA6+) peritoneal cavity macrophages. These macrophages provided a haven for S. aureus, thereby delaying the neutrophilic response in the peritoneum by 48 hours and allowing dissemination to various peritoneal and retroperitoneal organs including the kidneys. In mice deficient in GATA6+ peritoneal macrophages, neutrophils infiltrated more robustly and reduced S. aureus dissemination. Antibiotics administered i.v. did not prevent dissemination into the peritoneum or to the kidneys, whereas peritoneal administration of vancomycin (particularly liposomal vancomycin with optimized intracellular penetrance capacity) reduced kidney infection and mortality, even when administered 24 hours after infection. These data indicate that GATA6+ macrophages within the peritoneal cavity are a conduit of dissemination for i.v. S. aureus, and changing the route of antibiotic delivery could provide a more effective treatment for patients with peritonitis-associated bacterial sepsis.Copyright: © 2019, American Society for Clinical Investigation.

Epithelial ovarian cancer metastasis is driven by spheroids, which are heterogeneous cancer cell aggregates released from the primary tumour mass that passively disseminate throughout the peritoneal cavity to promote tumour spread, disease recurrence, and acquired chemoresistance. Despite their clinical importance, the molecular events that control spheroid attachment and invasion into underlying healthy tissues remain poorly understood. We examined a novel in vitro invasion model using imaging mass spectrometry to establish a "snapshot" of the spheroid/mesothelial interface. Amongst numerous adhesion-related proteins, we identified a sub-population of highly motile, invasive cells that expressed the basal epithelial marker KRT14 as an absolute determinant of invasive potential. The loss of KRT14 completely abrogated the invasive capacity, but had no impact on cell viability or proliferation, suggesting an invasion-specific role. Our data demonstrate KRT14 cells as an ovarian cancer "leader cell" phenotype underlying tumor invasion, and suggest their importance as a clinically relevant target in directed anti-tumour therapies.Copyright © 2019 by the authors.

Essentially all Staphylococcus aureus (S. aureus) bacteria that gain access to the circulation are plucked out of the bloodstream by the intravascular macrophages of the liver - the Kupffer cells. It is also thought that these bacteria are disseminated via the bloodstream to other organs. Our data show that S. aureus inside Kupffer cells grew and escaped across the mesothelium into the peritoneal cavity and immediately infected GATA-binding factor 6-positive (GATA6+) peritoneal cavity macrophages. These macrophages provided a haven for S. aureus, thereby delaying the neutrophilic response in the peritoneum by 48 hours and allowing dissemination to various peritoneal and retroperitoneal organs including the kidneys. In mice deficient in GATA6+ peritoneal macrophages, neutrophils infiltrated more robustly and reduced S. aureus dissemination. Antibiotics administered i.v. did not prevent dissemination into the peritoneum or to the kidneys, whereas peritoneal administration of vancomycin (particularly liposomal vancomycin with optimized intracellular penetrance capacity) reduced kidney infection and mortality, even when administered 24 hours after infection. These data indicate that GATA6+ macrophages within the peritoneal cavity are a conduit of dissemination for i.v. S. aureus, and changing the route of antibiotic delivery could provide a more effective treatment for patients with peritonitis-associated bacterial sepsis.Copyright: © 2019, American Society for Clinical Investigation.

Epithelial ovarian cancer metastasis is driven by spheroids, which are heterogeneous cancer cell aggregates released from the primary tumour mass that passively disseminate throughout the peritoneal cavity to promote tumour spread, disease recurrence, and acquired chemoresistance. Despite their clinical importance, the molecular events that control spheroid attachment and invasion into underlying healthy tissues remain poorly understood. We examined a novel in vitro invasion model using imaging mass spectrometry to establish a "snapshot" of the spheroid/mesothelial interface. Amongst numerous adhesion-related proteins, we identified a sub-population of highly motile, invasive cells that expressed the basal epithelial marker KRT14 as an absolute determinant of invasive potential. The loss of KRT14 completely abrogated the invasive capacity, but had no impact on cell viability or proliferation, suggesting an invasion-specific role. Our data demonstrate KRT14 cells as an ovarian cancer "leader cell" phenotype underlying tumor invasion, and suggest their importance as a clinically relevant target in directed anti-tumour therapies.Copyright © 2019 by the authors.

The Wilms tumor suppressor gene (Wt1) encodes a transcription factor involved in the development of a number of organs, but the role played by Wt1 in pancreatic development is unknown. The pancreas contains a population of pancreatic stellate cells (PSC) very important for pancreatic physiology. We described elsewhere that hepatic stellate cells originate from the WT1‐expressing liver mesothelium. Thus, we checked if the origin of PSCs was similar. WT1 expression is restricted to the pancreatic mesothelium. Between embryonic day (E) 10.5 and E15.5, this mesothelium gives rise to mesenchymal cells that contribute to a major part of the PSC and other cell types including endothelial cells. Most WT1 systemic mutants show abnormal localization of the dorsal pancreas within the mesentery and intestinal malrotation by E14.0. Embryos with conditional deletion of WT1 between E9.5 and E12.5 showed normal dorsal pancreatic bud and intestine, but the number of acini in the ventral bud was reduced approximately 30% by E16.5. Proliferation of acinar cells was reduced in WT1 systemic mutants, but pancreatic differentiation was not impaired. Thus, mesothelial‐derived cells constitute an important subpopulation of pancreatic mesodermal cells. WT1 expression is not essential for pancreas development, although it influences intestinal rotation and correct localization of the dorsal pancreas within the mesogastrium.

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Aim. The aim of this investigation was to examine the alterations in the peritoneum after cold dry CO2, heated dry CO2, and humidified heated CO2 at pressures equivalent to intraperitoneal pressures used in human laparoscopy. Methods. Eighteen rats were divided into 4 treatment groups—group 1: untreated control; group 2: insufflation with cold dry CO2; group 3: insufflation with heated, dry CO2; group 4: insufflation with heated and humidified CO2. The abdomen was insufflated to 5 mm/Hg (flow rate 50 mL/min) for 2 h. Twelve hours later, tissue samples were collected for analysis by light microscopy (LM) and scanning electron microscopy (SEM). Results. Group 1: no abnormalities were detected. Group 2: specimens revealed an inflammatory response with loss of mesothelium and mesothelial cell nuclei showing lytic change. Cells were rounded with some areas of cell flattening and separation. Group 3: some animals showed little or no alteration, while others had a mild inflammatory response. Mesothelial cells were rounded and showed crenation on the exposed surface. Group 4: specimens showed little change from the control group. Conclusions. The LM results indicate that insufflations with heated, humidified CO2 are the least likely to induce mesothelial damage.

Aim. The aim of this investigation was to examine the alterations in the peritoneum after cold dry CO2, heated dry CO2, and humidified heated CO2 at pressures equivalent to intraperitoneal pressures used in human laparoscopy. Methods. Eighteen rats were divided into 4 treatment groups—group 1: untreated control; group 2: insufflation with cold dry CO2; group 3: insufflation with heated, dry CO2; group 4: insufflation with heated and humidified CO2. The abdomen was insufflated to 5 mm/Hg (flow rate 50 mL/min) for 2 h. Twelve hours later, tissue samples were collected for analysis by light microscopy (LM) and scanning electron microscopy (SEM). Results. Group 1: no abnormalities were detected. Group 2: specimens revealed an inflammatory response with loss of mesothelium and mesothelial cell nuclei showing lytic change. Cells were rounded with some areas of cell flattening and separation. Group 3: some animals showed little or no alteration, while others had a mild inflammatory response. Mesothelial cells were rounded and showed crenation on the exposed surface. Group 4: specimens showed little change from the control group. Conclusions. The LM results indicate that insufflations with heated, humidified CO2 are the least likely to induce mesothelial damage.

Disseminated herpes simplex virus (HSV) infection usually manifests in the immunocompromised. However, anecdotal examples of visceral HSV disease and viremia have complicated type I diabetes. A case of a 53-year-old type I diabetic patient with bowel obstruction one week subsequent to bronchitis is reported. At laparotomy, a perforated segment of ileum was associated with an adhesive peritoneal band. HSV cytopathic atypia and HSV immunohistochemical staining were confined to fibrocytes and mesothelial cells without involvement of the epithelium. Dissemination of symptomatic HSV pneumonia was verified by histology, immunohistochemistry, in situ hybridization, polymerase chain reaction and direct fluorescence antibody. Intravenous acyclovir resolved symptoms. This is a novel documentation of HSV complicating ileal adhesive band disease. Furthermore, this case indicates that the HSV cytopathic effect is not unique to the epithelium. Disseminated infection can manifest in myofibrocytes and mesothelium, distinguishing it from standard epithelial atypia of localized HSV infection.

BACKGROUND: Initial studies of adenovirus-mediated gene transfer to the peritoneum have shown transgene expression in the mesothelium from the parietal peritoneum. Using a replication-deficient adenovirus encoding beta-galactosidase (Ad beta Gal), we investigated the expression efficiency and the distribution of the transgene to different areas of both visceral and parietal peritoneum and to extra-peritoneal tissues. METHODS: Male Wistar rats received an intraperitoneal injection of 15 ml of 0.9% NaCl alone or containing 1 x 10(9) or 3 x 10(9) p.f.u. of Ad beta Gal. Evaluations of the histology of the peritoneum, the transgene expression and the safety of adenovirus-mediated gene transfer, using measurement of both beta Gal activity and staining, were performed 1, 3 and 5 days post-injection. RESULTS: At 1 day post-injection of 3 x 10(9) p.f.u. of Ad beta Gal, significant beta Gal activity and staining were detected in the omentum and mesenteric peritoneum. beta Gal staining was observed in endothelial cells, mesothelial cells and adipocytes. Focal mononuclear infiltrates restricted to the submesothelial area of the visceral peritoneum were also observed. No expression was detected in the mesocolon and parietal peritoneum, where the mesothelium was damaged. Significant beta Gal activity and staining were observed in lymph nodes, lungs, liver, heart and kidneys, in the absence of inflammatory changes. CONCLUSIONS: Intraperitoneal delivery of adenoviral vectors allows highly efficient transgene expression in mesothelial cells, but also in endothelial cells and adipocytes of the visceral peritoneum. Adverse focal mononuclear infiltrates, as well as spreading of the adenoviral vector from the abdominal cavity to the systemic circulation, were observed in parallel. Transgene expression in endothelial cells is potentially important since the latter play a key role in the alterations of the peritoneal membrane associated with long-term peritoneal dialysis. However, these d

BACKGROUND: Initial studies of adenovirus-mediated gene transfer to the peritoneum have shown transgene expression in the mesothelium from the parietal peritoneum. Using a replication-deficient adenovirus encoding beta-galactosidase (Ad beta Gal), we investigated the expression efficiency and the distribution of the transgene to different areas of both visceral and parietal peritoneum and to extra-peritoneal tissues. METHODS: Male Wistar rats received an intraperitoneal injection of 15 ml of 0.9% NaCl alone or containing 1 x 10(9) or 3 x 10(9) p.f.u. of Ad beta Gal. Evaluations of the histology of the peritoneum, the transgene expression and the safety of adenovirus-mediated gene transfer, using measurement of both beta Gal activity and staining, were performed 1, 3 and 5 days post-injection. RESULTS: At 1 day post-injection of 3 x 10(9) p.f.u. of Ad beta Gal, significant beta Gal activity and staining were detected in the omentum and mesenteric peritoneum. beta Gal staining was observed in endothelial cells, mesothelial cells and adipocytes. Focal mononuclear infiltrates restricted to the submesothelial area of the visceral peritoneum were also observed. No expression was detected in the mesocolon and parietal peritoneum, where the mesothelium was damaged. Significant beta Gal activity and staining were observed in lymph nodes, lungs, liver, heart and kidneys, in the absence of inflammatory changes. CONCLUSIONS: Intraperitoneal delivery of adenoviral vectors allows highly efficient transgene expression in mesothelial cells, but also in endothelial cells and adipocytes of the visceral peritoneum. Adverse focal mononuclear infiltrates, as well as spreading of the adenoviral vector from the abdominal cavity to the systemic circulation, were observed in parallel. Transgene expression in endothelial cells is potentially important since the latter play a key role in the alterations of the peritoneal membrane associated with long-term peritoneal dialysis. However, these d, Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

BACKGROUND: Initial studies of adenovirus-mediated gene transfer to the peritoneum have shown transgene expression in the mesothelium from the parietal peritoneum. Using a replication-deficient adenovirus encoding beta-galactosidase (Ad beta Gal), we investigated the expression efficiency and the distribution of the transgene to different areas of both visceral and parietal peritoneum and to extra-peritoneal tissues. METHODS: Male Wistar rats received an intraperitoneal injection of 15 ml of 0.9% NaCl alone or containing 1 x 10(9) or 3 x 10(9) p.f.u. of Ad beta Gal. Evaluations of the histology of the peritoneum, the transgene expression and the safety of adenovirus-mediated gene transfer, using measurement of both beta Gal activity and staining, were performed 1, 3 and 5 days post-injection. RESULTS: At 1 day post-injection of 3 x 10(9) p.f.u. of Ad beta Gal, significant beta Gal activity and staining were detected in the omentum and mesenteric peritoneum. beta Gal staining was observed in endothelial cells, mesothelial cells and adipocytes. Focal mononuclear infiltrates restricted to the submesothelial area of the visceral peritoneum were also observed. No expression was detected in the mesocolon and parietal peritoneum, where the mesothelium was damaged. Significant beta Gal activity and staining were observed in lymph nodes, lungs, liver, heart and kidneys, in the absence of inflammatory changes. CONCLUSIONS: Intraperitoneal delivery of adenoviral vectors allows highly efficient transgene expression in mesothelial cells, but also in endothelial cells and adipocytes of the visceral peritoneum. Adverse focal mononuclear infiltrates, as well as spreading of the adenoviral vector from the abdominal cavity to the systemic circulation, were observed in parallel. Transgene expression in endothelial cells is potentially important since the latter play a key role in the alterations of the peritoneal membrane associated with long-term peritoneal dialysis. However, these d, Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

Vascular endothelial growth factor (VEGF) and semaphorin-3A (Sema-3A) play important roles in the transduction of promitotic and antimitotic signals, respectively. Here, we report that these conflicting signals are integrated via negative feedback between VEGF and Sema-3A pathways in several primary normal, but not malignant, mesothelial cells. Unlike malignant mesothelial (MM) cells, in which VEGF induces cell proliferation, normal mesothelial (NM) cell growth was repressed by VEGF. Although both cell-types expressed an overlapping set of VEGF tyrosine-kinase receptors, only in NM cells VEGF exposure entails a p38 mitogen-activated protein kinase (MAPK)-dependent increased of Sema-3A production. Inhibition of p38 MAPK (by SB202190 and SB203580) or a dominant-negative mutant of Sema-3A receptor plexin-A1 reversed the inhibitory effects of VEGF in NM cells, increasing cyclin D1 synthesis and cell growth. Conversely, sustained activation of p38 MAPK by the p38 MAPK-activating kinases MKK3 and MKK6 or transfection with Sema-3A inhibited VEGF-induced cyclin D1 up-regulation and MM cell proliferation. Therefore, these results delineate a new role of Sema-3A in VEGF function mediated by p38 MAPK and suggest that the abrogation of regulated Sema-3A expression is responsible for VEGF-driven growth of tumor cells.

Objective: To test whether hemoglobin may accumulate in the peritoneal cavity in case of endometriosis and to assess whether heme oxygenases (HO), detoxifying heme, are expressed in ectopic endometrium and peritoneal cells. Design: Prospective study involving patients with and without endometriosis. Setting: Department of gynecology in a university hospital. Patient(s): Seventy-six patients undergoing laparoscopy for tubal sterilization or infertility and/or pelvic pain. Intervention(s): Collection of peritoneal fluid (PF), blood samples, and biopsies from endometrium and peritoneum. Main Outcome Measure(s): Measurement of free hemoglobin and its byproduct, total and direct bilirubin, in serum and PF and analysis of HO-1 and HO-2 expression in biopsies by reverse transcription polymerase chain reaction and semiquantitative immunohistochemistry. Result(s): Higher levels of hemoglobin were found in the PF of patients with endometriosis. There was no concomitant increase in bilirubin concentrations in the PF, and HO-1 was poorly expressed in peritoneal mesothelium and macrophages. Heme oxygenase-1 and HO-2 were strongly expressed in ectopic endometrium, especially in red lesions. Conclusion(s): Our results suggest that heme may be involved in the pathogenesis and/or development of endometriosis and that the HO system, although expressed, might be insufficient to detoxify heme in women with endometriosis. Copyright © 2002 American Society for Reproductive Medicine., SCOPUS: ar.j, info:eu-repo/semantics/published

Twenty peritoneal specimens, collected from 19 patients at the insertion or removal of the catheter for continuous ambulatory peritoneal dialysis (CAPD), were examined by light microscopy (LM) and transmission and scanning electron microscopy (TEM and SEM). During long-term CAPD, the peritoneal tissue showed an absence of mesothelial cells and a fibrous thickening by proliferation of degenerative collagen fibers. Ultrastructural examination by SEM revealed that the surface of the peritoneum with mesothelial denudation was covered by a continuous sheet of homogeneous material (a membrane structure) in patients in an the early stage of peritonitis. In cases in the advanced stage, the membrane structure covered the irregular collagen bundles, which occasionally showed through breaks in the membrane-like structure. Vascular alterations characterized by the hyalinous degeneration of media, the thickening of the basement membrane in small vasculature, and lymphatic dilatation were observed by TEM in cases of sclerosing peritonitis. Our results suggest that the pathological changes of the peritoneal surface and peripheral blood and lymphatic circulatory impairment may be related to ultrafiltration failure and the progression of pathological process during CAPD., Acta medica Nagasakiensia. 1997, 42(1-2), p.5-11