Mesothelial-to-Mesenchymal Transition and Exosomes in Peritoneal Metastasis of Ovarian Cancer

Most patients with ovarian cancer (OvCA) present peritoneal disseminated disease at the time of diagnosis. During peritoneal metastasis, cancer cells detach from the primary tumor and disseminate through the intraperitoneal fluid. The peritoneal mesothelial cell (PMC) monolayer that lines the abdominal cavity is the first barrier encountered by OvCA cells. Subsequent progression of tumors through the peritoneum leads to the accumulation into the peritoneal stroma of a sizeable population of carcinoma-associated fibroblasts (CAFs), which is mainly originated from a mesothelial-to-mesenchymal transition (MMT) process. A common characteristic of OvCA patients is the intraperitoneal accumulation of ascitic fluid, which is composed of cytokines, chemokines, growth factors, miRNAs, and proteins contained in exosomes, as well as tumor and mesothelial suspended cells, among other components that vary in proportion between patients. Exosomes are small extracellular vesicles that have been shown to mediate peritoneal metastasis by educating a pre-metastatic niche, promoting the accumulation of CAFs via MMT, and inducing tumor growth and chemoresistance. This review summarizes and discusses the pivotal role of exosomes and MMT as mediators of OvCA peritoneal colonization and as emerging diagnostic and therapeutic targets.

A comparison of the analysis of 3 types of body fluids using the XN-350 hematology analyzer versus light microscopy assessment

We evaluated the capacity of the XN-350 instrument to analyze 3 different types of body fluid samples under "body fluid mode."The performance of XN-350 was evaluated in terms of precision, carryover, limit of blank, limit of detection, limit of quantification, and linearity. Cell enumeration and differential data produced by the XN-350 were compared to manual chamber counting results in 63 cerebrospinal fluid (CSF), 51 ascitic fluid, and 51 pleural fluid (PF) samples. Comparisons between XN-350 versus Cytospin data were also performed in PF samples.The precision, carry-over, limit of blank, and linearity of the XN-350 were acceptable. The limits of detection for white blood cells (WBCs) and red blood cells were 1.0/μL, and 1,000.0/μL, respectively; the corresponding limits of quantitation (LOQs) were 5.0/μL and 2,000.0/μL, respectively. The XN-350's cell enumeration and differential counting correlated well with those of manual chamber counting for all 3 sample types (except for differential counting in CSF samples), particularly parameters involving monocytes (r = 0.33) and mononuclear cells (MO- body fluid [BF]; r = 0.26), as well as total cell (TC-BF) enumeration (r = 0.50) and WBC-BF (r = 0.50) in PF samples. The MO-BF in CSF samples differed significantly from manual chamber counting results, but neither TC-BF nor WBC-BF in PF samples did. The XN-350 also showed good correlations with Cytospin analyses for differential counting of neutrophils, lymphocytes, and monocytes in PF samples. The differential counting of eosinophils via the XN-350 and Cytospin were not significantly correlated, but the difference between them was not significant.The XN-350 is an acceptable alternative to manual fluid analysis. Samples with low cellularity around the LOQ should be checked manually. Moreover, manual differential counting should be performed on CSF samples, particularity those with low cell numbers.

Mucosal-Associated Invariant T Cells Redistribute to the Peritoneal Cavity During Spontaneous Bacterial Peritonitis and Contribute to Peritoneal Inflammation

BACKGROUND & AIMS

Mucosal-associated invariant T (MAIT) cells are depleted from blood in patients with advanced liver disease and show features of immune dysfunction. Because circulating MAIT cells differ from organ-resident MAIT cells, we aimed to investigate the frequency, phenotype, and function of peritoneal MAIT cells from patients with cirrhosis and spontaneous bacterial peritonitis (SBP).

METHODS

MAIT cells in blood and ascitic fluid from patients with cirrhosis were characterized using flow cytometry. Healthy individuals and noncirrhotic patients undergoing peritoneal dialysis served as controls. MAIT cell migration was studied in transwell assays. Cytokine release in response to infected ascitic fluid and bacterial products was assessed in vitro.

RESULTS

Peritoneal CD3+ CD161hi Vα7.2+ T cells had an inflammatory, tissue retention phenotype, expressing the alpha E integrin, the chemokine receptors CCR5 and CXCR3, and the activation marker CD69 at higher levels than their circulating equivalents. Seventy-seven percent bound to MR1 tetramers loaded with the pyrimidine intermediate 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil. The ratio of peritoneal to blood MAIT cell frequency increased from 1.3 in the absence of SBP to 2.6 at diagnosis and decreased by day 3. MAIT cells migrated toward infected ascitic fluid containing CCL5 and CCL20 and released cytokines in an MR1-restricted fashion. Whereas the depleted circulating MAIT cell pool displayed features of immune exhaustion, peritoneal MAIT cells remained competent producers of inflammatory cytokines in response to bacterial products. Peritoneal MAIT activation correlated with systemic inflammation, suggesting a possible link between peritoneal and systemic immunity.

CONCLUSIONS

Peritoneal MAIT cells phenotypically and functionally differ from circulating MAIT cells in decompensated cirrhosis and redistribute to the peritoneum during SBP.

Characterizing the Effect of Automated Cell Sorting Solutions on Cytomorphological Changes

INTRODUCTION

Liquid-based cytology has become a widely adopted, automated screening system for gynecologic and nongynecologic cytology. Automated screening systems function by distinguishing atypical cells based on their cytoplasmic and nuclear areas, densitometric measurement, and so on. However, the morphological influence of the washing solution has not been fully considered. Here, we examined the morphological effect and temporal change resulting from saving the cytologic samples in various solutions.

METHODS

Cytologic specimens were obtained from the ascites (AS) of patients with peritoneal cancer. Various solutions of a physiological saline, a Ringer's solution, a low-molecular dextran L injection, VOLUVEN 6% solution, MIXID L injection (ML), RPMI-1640 medium, and horse serum (HS) were added to aliquot sediments. All samples were refrigerated at 4°C, and aliquots were subsequently processed at specific time points (0, 1, 2, 4, 7, and 14 days). For all samples, cytoplasmic and nuclear size of the Papanicolaou-stained specimens were measured.

RESULTS

In terms of cytoplasmic and nuclear areas, samples stored in ML and HS showed no significant difference compared to the AS sample; in contrast, the other samples were significantly larger in both cytoplasmic and nuclear areas than the AS sample. In examining the temporal change among the solutions, we found that the cytoplasms and nuclei became small over the time course for all of the tested solutions.

CONCLUSION

We showed that cells swell in the solution after 1 h of storage and contract as time progresses. Together, our findings have important implications for how mathematical analysis is applied during the automated screening process.

Announcement: The International System for Reporting Serous Fluid Cytopathology

Serous fluids are a common but important specimen type in a cytopathology laboratory. There is as yet no agreed standardized terminology to allow uniformity in reporting on these specimens. Given that serous fluids are a rich source of cytopathological as well as molecular information on a range of benign and often advanced malignant conditions, a unified approach to handling and reporting these specimens covering the pre-analytical, analytical and postanalytical stages seems timely. Representatives of the international cytology community have come together once again to develop an algorithmic diagnostic and management approach to the reporting of these samples.

A rare agent of continuous ambulatory peritoneal dialysis peritonitis: Rhizobium Radiobacter

Peritonitis is a common clinical problem in patients treated by continuous ambulatory peritoneal dialysis (CAPD). The most common microbiological factors causing peritonitis are Gram-positive (especially Staphylococcus spp.). Peritonitis with Rhizobium radiobacter (Agrobacterium radiobacter) is a rare infection in CAPD patients. Peritonitis due to R. radiobacter has been reported in our patient's dialysate culture who underwent CAPD for three years. We report the case of a 26-year-old female PD patient who had CAPD peritonitis due to R. radiobacter and successfully treated with intraperitoneal vancomycin and oral ciprofloxacin without relapses or removing the PD catheter.

Performance Evaluation of a New Generation of Automated Analyzer for Pleural and Peritoneal Fluids Cytology

BACKGROUND

Hematologic counters with dedicated body fluids mode allows these samples to be analyzed in an automated manner. Our aim was to evaluate the performance of the Sysmex XN-3000 and compare it with the Sysmex XE-5000, in use in our laboratory for cytological analysis of body fluids.

METHODS

We studied 108 pleural and peritoneal fluids. Laboratory routine included manual and automated cell counts. The Sysmex XN-3000 validation protocol included precision, carryover, linearity studies, and comparison with traditional microscopic differential counts and with the analyzer in use.

RESULTS

Sysmex XN-3000 met all the criteria for analytical quality with strong correlation with microscopy (r = 0.95 for MN and PMN) and agreement of 93% (kappa = 0.813, p < 0.0001). Comparison between both analyzers revealed no significant differences and strong correlation regarding WBC and RBC (r > 0.98), mononuclear and polymorphonuclear cells (r = 0.99).

CONCLUSIONS

Sysmex XN-3000 showed strong correlation and agreement with traditional microscopy with an equivalent performance compared to the XE-5000.

Eosinophilia in a peritoneal dialysis patient: Answers

Icodextrin is a starch-derived glucose polymer used in peritoneal dialysis dialysate to treat volume overload by increasing ultrafiltration in patients with end-stage renal disease. Reported adverse reactions to icodextrin are mild and rare and mainly consist of skin rash that resolves spontaneously after discontinuation of treatment. We describe a young patient with extreme eosinophilia that appeared with the use of icodextrin, disappeared after its discontinuation, and reappeared after a rechallenge with the drug. The eosinophilia was not associated with peritonitis, was asymptomatic, and fully resolved after discontinuation of the drug. Severe eosinophilia can potentially cause tissue damage in several organs, which would indicate that blood eosinophil count is recommended in routine complete blood counts while icodextrin peritoneal dialysis is being administered.

Laparoscopy Combined with Peritoneal Cytology in Staging and Restaging Ovarian Carcinoma

The merits of laparoscopy, with inspection of the diaphragmatic leaves, and of peritoneal cytology (free fluid or washing) in staging and restaging were studied in 153 patients with ovarian carcinoma. Of 153 patients examined, 83 were new cases, 34 were restaging in patients without clinical and/or radiological signs of disease, and 36 in patients with evident disease. The conversion rate for diaphragmatic metastases alone was 6%. Information about the spread of disease (diaphragmatic metastases) was obtained in 33 new cases (39.7%). In pretreated patients, laparoscopy was positive in 4 of 34 NED restaging and in 24 of 36 ED restaging. The conversion rate for peritoneal cytology was 6.6%, but information about the cellular intraperitoneal spread of the disease was obtained in 31 new cases (37.8%). In pretreated patients, peritoneal cytology was positive in 4 of 34 NED restaging and in 13 of 36 ED restaging.

Significance of Ascitic Fluid and Peritoneal Washing Cytology in Ovarian Tumor Diagnosis

The results of the cytological test on 179 ascitic fluids and 88 peritoneal washes of patients suspected to have ovarian tumors are critically reviewed to illustrate the difficulties, limitations and future possibilites of this technique. Tissue correlation was available in all cases. The data was evaluated in order to obtain information as to the accuracy, sensitivity and specificity of cytological examination, both in ascitic fluids and in peritoneal washings. A correct diagnosis as to the ovarian tumor histotype was obtained in more than 80 per cent of the cases.

The Role of Liquid Based Cytology and Ancillary Techniques in the Peritoneal Washing Analysis: Our Institutional Experience

Background

The cytological analysis of peritoneal effusions serves as a diagnostic and prognostic aid for either primary or metastatic diseases. Among the different cytological preparations, liquid based cytology (LBC) represents a feasible and reliable method ensuring also the application of ancillary techniques (i.e immunocytochemistry-ICC and molecular testing).

Methods

We recorded 10348 LBC peritoneal effusions between January 2000 and December 2014. They were classified as non-diagnostic (ND), negative for malignancy-NM, atypical-suspicious for malignancy-SM and positive for malignancy-PM.

Results

The cytological diagnosis included 218 ND, 9.035 NM, 213 SM and 882 PM. A total of 8048 (7228 NM, 115SM, 705 PM) cases with histological follow-up were included. Our NM included 21 malignant and 7207 benign histological diagnoses. Our 820 SMs+PMs were diagnosed as 107 unknown malignancies (30SM and 77PM), 691 metastatic lesions (81SM and 610PM), 9 lymphomas (2SM and 7PM), 9 mesotheliomas (1SM and 8SM), 4 sarcomas (1SM and 3PM). Primary gynecological cancers contributed with 64% of the cases. We documented 97.4% sensitivity, 99.9% specificity, 98% diagnostic accuracy, 99.7% negative predictive value (NPV) and 99.7% positive predictive value (PPV). Furthermore, the morphological diagnoses were supported by either 173 conclusive ICC results or 50 molecular analyses. Specifically the molecular testing was performed for the EGFR and KRAS mutational analysis based on the previous or contemporary diagnoses of Non Small Cell Lung Cancer (NSCLC) and colon carcinomas. We identified 10 EGFR in NSCCL and 7 KRAS mutations on LBC stored material.

Conclusions

Peritoneal cytology is an adjunctive tool in the surgical management of tumors mostly gynecological cancers. LBC maximizes the application of ancillary techniques such as ICC and molecular analysis with feasible diagnostic and predictive yields also in controversial cases.

Mesenchymal stroma cells in peritoneal dialysis effluents from patients

Mesenchymal stroma cells (MSCs) have potential as an emerging cell therapy for treating many different diseases, but discovery of the practical sources of MSCs is needed for the large-scale clinical application of this therapy. This study was to identify MSCs in peritoneal dialysis (PD) effluents that were discarded after PD. The effluents were collected from patients who were on the dialysis for less than 1 month. Adherent cells from the effluents were isolated by incubation in serum-containing medium in plastic culture dishes. Cell surface markers were determined by a flow cytometric analysis, and the in vitro differentiation to chondrocytes, osteocytes or adipocytes was confirmed by staining with a specific dye. After four passages, these isolated cells displayed the typical morphology of mesenchymal cells in traditional 2-D cultures, and were grown to form spherical colonies in 3-D collagen cultures. Flow cytometric analysis revealed that the unsorted cells from all of seven patient samples showed robust expression of typical mesenchymal marker CD29, CD44, CD73, CD90 and CD166, and the absence of CD34, CD79a, CD105, CD271, SSEA-4, Stro-1 and HLA-DR. In differentiation assays, these cells were induced in vitro to chondrocytes, osteocytes or adipocytes. In conclusion, this preliminary study suggests the presence of MSCs in the “discarded” PD effluents. Further characterization of the phenotypes of these MSCs and evaluation of their therapeutic potential, particularly for the prevention of PD failure, are needed.

The diagnostic work-up in patients with ascites: current guidelines and future prospects

Accumulation of fluid in the peritoneal cavity - ascites - is commonly encountered in clinical practice. Ascites can originate from hepatic, malignant, cardiac, renal, and infectious diseases. This review discusses the current recommended diagnostic approach towards the patient with ascites and summarises future diagnostic targets.

Evaluation of peripheral blood and abdominal fluid variables as predictors of intestinal surgical site failure in dogs with septic peritonitis following celiotomy and the placement of closed-suction abdominal drains

OBJECTIVE To evaluate peripheral blood and abdominal fluid variables as predictors of intestinal surgical site failure in dogs with septic peritonitis following celiotomy and closed-suction abdominal drain (CSAD) placement. DESIGN Prospective study. ANIMALS 26 dogs with septic peritonitis that underwent celiotomy and CSAD placement. PROCEDURES Abdominal fluid and blood samples were collected prior to surgery and daily thereafter until CSAD removal. Abdominal fluid was collected through the CSAD. Analysis of all samples included pH, PCO2, PO2, PCV, WBC count, and total solids, glucose, lactate, and electrolyte concentrations. Abdominal fluid samples also underwent cytologic evaluation and bacterial culture, and the volume of fluid removed through the drain was recorded daily. The blood-to-fluid glucose and lactate differences, fluid-to-blood lactate ratio and blood-to-fluid WBC and neutrophil ratios were determined daily. Dogs were categorized into 2 groups on the basis of whether they had an uneventful recovery (UR) or developed postoperative septic peritonitis (POSP). RESULTS 23 dogs had a UR and 3 developed POSP. On the third day after surgery, the abdominal fluid WBC count was significantly lower and the blood-to-fluid WBC and neutrophil ratios were significantly higher for dogs in the POSP group, compared with those for dogs in the UR group. None of the other blood and abdominal fluid variables assessed differed significantly between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Results failed to identify any objective predictive indicators for POSP in dogs with CSADs. Use of blood-to-fluid WBC and neutrophil ratios as predictive indicators for POSP requires further investigation.

Reagent strips are efficient to rule out spontaneous bacterial peritonitis in cirrhotics

BACKGROUND

The gold standard to diagnose spontaneous bacterial peritonitis (SBP) is a polymorphonuclear neutrophil count ≥ 250 cells/µl in ascitic fluid. This test is laborious and expensive. Urine reagent strips measuring leukocyte esterase activity have been proposed as a rapid and inexpensive alternative. The aim of this study was to assess the diagnostic accuracy of the Combur reagent strip for diagnosing SBP. Furthermore the possible advantage of a photospectrometer reading over visual reading of the strip was investigated.

METHODS

This prospective study includes all ascitic fluid samples of cirrhotic patients undergoing diagnostic or therapeutic paracentesis over a 12-month period. The samples were collected for the standard diagnostic work-up and in addition tested with a bedside Combur reagent strip. The strip was read visually and with an automated spectrometer.

RESULTS

A total of 157 samples were obtained from 53 patients, and spontaneous bacterial peritonitis was diagnosed in 12 patients based on the ascitic polymorphonuclear neutrophil count. The sensitivity, specificity, positive predictive value and negative predictive value of the reagent strip according to the photospectrometer were 100%, 93%, 55% and 100% respectively, and 75%, 99%, 82% and 98%, respectively, for visual interpretation. The diagnostic accuracy of the photospectrometer was found to be higher than visual interpretation (p = 0.007).

CONCLUSION

The diagnostic accuracy of leucocyte esterase reagent strips read out by a photospectrometer was comparable with the gold standard test and was excellent for excluding SBP. Our results support implementation of reagent strips in the diagnostic work-up of ascitic fluid.

Plaque Size Is Decreased but M1 Macrophage Polarization and Rupture Related Metalloproteinase Expression Are Maintained after Deleting T-Bet in ApoE Null Mice

Background

Thelper1 (Th1) lymphocytes have been previously implicated in atherosclerotic plaque growth but their role in plaque vulnerability to rupture is less clear. We investigated whether T-bet knockout that prevents Th1 lymphocyte differentiation modulates classical (M1) macrophage activation or production of matrix degrading metalloproteinases (MMPs) and their tissue inhibitors, TIMPs.

Methods & Results

We studied the effect of T-bet deletion in apolipoproteinE (ApoE) knockout mice fed a high fat diet (HFD) or normal chow diet (ND). Transcript levels of M1/M2 macrophage polarization markers, selected MMPs and TIMPs were measured by RT-qPCR in macrophages isolated from subcutaneous granulomas or in whole aortae. Immunohistochemistry of aortic sinus (AS) and brachiocephalic artery (BCA) plaques was conducted to quantify protein expression of the same factors.

Deletion of T-bet decreased mRNA for the M1 marker NOS-2 in granuloma macrophages but levels of M2 markers (CD206, arginase-1 and Ym-1), MMPs-2, -9, -12, -13, -14 and -19 or TIMPs-1 to -3 were unchanged. No mRNA differences were observed in aortic extracts from mice fed a HFD for 12 weeks. Moreover, AS and BCA plaques were similarly sized between genotypes, and had similar areas stained for NOS-2, COX-2, MMP-12 and MMP-14 proteins. T-bet deletion increased MMP-13, MMP-14 and arginase-1 in AS plaques. After 35 weeks of ND, T-bet deletion reduced the size of AS and BCA plaques but there were no differences in the percentage areas stained for M1 or M2 markers, MMPs-12, -13, -14, or TIMP-3.

Conclusions

Absence of Th1 lymphocytes is associated with reduced plaque size in ApoE knockout mice fed a normal but not high fat diet. In either case, M1 macrophage polarization and expression of several MMPs related to plaque instability are either maintained or increased.

Cytomorphometry of serosal effusion in dogs

Cytomorphometry made on cytological slides is the quantitative method of precise analysis of cellular structures, including both cytoplasm and nucleus. The aim of this study was to describe cytomorphometric parameters of mesothelial cells in the course of benign reactive and malignant proliferation and to compare them to carcinomas and adenocarcinomas located within serosal cavities in dogs. The second aim was to evaluate applicability of cytomorphometry to diagnostics of diseases causing accumulation of effusion in serosal cavities. Cytological samples of normal and non-malignant mesothelium, mesothelioma and various carcinomas were collected from dogs. Cytomorphometry was made on the smears stained with Giemsa solution. Mean nuclear and cellular perimeter, mean nuclear and cellular area, mean nuclear and cellular diameter, and mean nuclear and cellular roundness were determined. Moreover, nuclear to cytoplasmic ratio (N/C) was calculated. The data revealed statistically significant differences for all parameters, excluding mean nuclear perimeter, between compared groups. Normal mesothelium cells and their nuclei were significantly smaller and more elongated than cells and nuclei of both benign reactive and malignant neoplastic mesothelium. Only a few differences were observed between benign reactive mesothelium cells and mesothelioma cells - mean nuclear area and mean nuclear diameter of benign reactive mesothelium cells were significantly larger and N/C ratio was higher in comparison to mesothelioma cells. Even though some significant differences were observed, considerable overlap of these cytomorphometric parameters in animals with different diseases limited practical role of these observations. Cytomorphometric analysis of cellular samples collected from dogs with proliferative processes affecting serosal cavities can be only an auxiliary method increasing accuracy of preoperative diagnosis.

Isolation of Mouse Neutrophils

Neutrophils represent the first line of defense against bacterial and fungal pathogens. Indeed, patients with inherited and acquired qualitative and quantitative neutrophil defects are at high risk for developing bacterial and fungal infections and suffering adverse outcomes from these infections. Therefore, research aiming at defining the molecular factors that modulate neutrophil effector function under homeostatic conditions and during infection is essential for devising strategies to augment neutrophil function and improve the outcome of infected individuals. This unit describes a reproducible density gradient centrifugation-based protocol that can be applied in any laboratory to harvest large numbers of highly enriched and highly viable neutrophils from the bone marrow of mice both at the steady state and following infection with Candida albicans as described in UNIT. In another protocol, we also present a method that combines gentle enzymatic tissue digestion with a positive immunomagnetic selection technique or Fluorescence-activated cell sorting (FACS) to harvest highly pure and highly viable preparations of neutrophils directly from mouse tissues such as the kidney, the liver or the spleen. Finally, methods for isolating neutrophils from mouse peritoneal fluid and peripheral blood are included. Mouse neutrophils isolated by these protocols can be used for examining several aspects of cellular function ex vivo including pathogen binding, phagocytosis and killing, neutrophil chemotaxis, oxidative burst, degranulation and cytokine production, and for performing neutrophil adoptive transfer experiments.

Ascites bacterial burden and immune cell profile are associated with poor clinical outcomes in the absence of overt infection

Bacterial infections, most commonly spontaneous bacterial peritonitis in patients with ascites, occur in one third of admitted patients with cirrhosis, and account for a 4-fold increase in mortality. Bacteria are isolated from less than 40% of ascites infections by culture, necessitating empirical antibiotic treatment, but culture-independent studies suggest bacteria are commonly present, even in the absence of overt infection. Widespread detection of low levels of bacteria in ascites, in the absence of peritonitis, suggests immune impairment may contribute to higher susceptibility to infection in cirrhotic patients. However, little is known about the role of ascites leukocyte composition and function in this context. We determined ascites bacterial composition by quantitative PCR and 16S rRNA gene sequencing in 25 patients with culture-negative, non-neutrocytic ascites, and compared microbiological data with ascites and peripheral blood leukocyte composition and phenotype. Bacterial DNA was detected in ascitic fluid from 23 of 25 patients, with significant positive correlations between bacterial DNA levels and poor 6-month clinical outcomes (death, readmission). Ascites leukocyte composition was variable, but dominated by macrophages or T lymphocytes, with lower numbers of B lymphocytes and natural killer cells. Consistent with the hypothesis that impaired innate immunity contributes to susceptibility to infection, high bacterial DNA burden was associated with reduced major histocompatibility complex class II expression on ascites (but not peripheral blood) monocytes/macrophages. These data indicate an association between the presence of ascites bacterial DNA and early death and readmission in patients with decompensated cirrhosis. They further suggest that impairment of innate immunity contributes to increased bacterial translocation, risk of peritonitis, or both.

Absent in melanoma 2 triggers a heightened inflammasome response in ascitic fluid macrophages of patients with cirrhosis

BACKGROUND & AIMS

Inflammation is a common event in the pathogenesis of liver cirrhosis. The inflammasome pathway has acquired significant relevance in the pathogenesis of inflammation, but its role in the inflammatory response in patients with decompensated cirrhosis remains unexplored.

METHODS

We performed a prospective study in which 44 patients with decompensated cirrhosis and 12 healthy volunteers were included. We isolated macrophages from blood and ascitic fluid and assessed the expression and activation of the inflammasome, its response to priming by bacterial products, and its association with the degree of liver disease.

RESULTS

Macrophages from sterile ascitic fluids showed constitutive activation of caspase-1 and a marked increase in the expression of IL-1β, IL-18, and absent in melanoma 2 (AIM2) when compared to blood macrophages. Pre-stimulation of blood-derived macrophages from cirrhotic patients with bacterial DNA increased the expression of AIM2 and induced a higher AIM2-mediated inflammasome response than priming with other bacterial products such as lipopolysaccharide. By contrast, activation of the AIM2 inflammasome did not require a priming signal in ascitic fluid-derived macrophages, demonstrating the preactivated state of the inflammasome in these cells. Last, higher IL-1β and IL-18 production by ascitic fluid macrophages correlated with a more advanced Child-Pugh score.

CONCLUSIONS

The inflammasome is highly activated in the ascitic fluid of cirrhotic patients, which may explain the exacerbated inflammatory response observed in these patients under non-infected conditions. Clinically, activation of the inflammasome is associated with a higher degree of liver disease.

A rapid and non-invasive 2-step algorithm for diagnosing tuberculous peritonitis using a T cell-based assay on peripheral blood and peritoneal fluid mononuclear cells together with peritoneal fluid adenosine deaminase

OBJECTIVES

A recently developed RD-1 gene-based assay for diagnosing tuberculous peritonitis (TBP) has given promising results. We therefore created a clinical algorithm for differentiating TBP from other diagnoses using peripheral blood and peritoneal fluid mononuclear cells (PBMC/PF-MC) along with conventional tests.

METHODS

All adult patients with suspected TBP in whom enzyme-linked immunosorbent spot (ELISPOT) assays were performed both on PBMC and PF-MC were prospectively enrolled over a 6-year period. Confirmed TBP with positive cultures or Mycobacterium tuberculosis PCR, probable TBP with PF changes consistent with TBP, caseating granuloma, and a successful response to anti-TB therapy, as well as possible TBP without exclusion of TBP, were each defined.

RESULTS

A total of 74 patients were enrolled. Of these, 45 (61%) (19 confirmed, 16 probable, and 10 possible) were classified as TBP. The other 29 (39%) patients were classified as not TB. The sensitivity and specificity, respectively, of the tested methods for diagnosing TBP were as follows: PBMC ELISPOT (≥6 spots), 84% and 59%; PF-MC ELISPOT (≥6 spots), 87% and 86%; PF-MC/PBMC ratio (≥3), 69% and 97%; and PF-ADA level (≥21 U/L), 82% and 79%. The areas under the ROC curves were as follows: PF-MC ELISPOT, 0.90; PF-MC/PBMC ratio, 0.82; PBMC ELISPOT, 0.80; and PF-ADA, 0.80, respectively. When a 2-step algorithm ('PBMC ELISPOT ≥6 spots or PF-ADA ≥21 U/L' as a rule-out test and 'PF-MC/PBMC ratio ≥3' as a rule-in test) was applied, 67% (30/45) of the patients with TBP were accurately classified without undergoing invasive procedures.

CONCLUSIONS

A 2-step algorithm using the PBMC/PF-MC ELISPOT assays and PF-ADA appears to be a promising rapid and non-invasive approach for diagnosing TBP.

Immunological screening for tumor cells in serous body fluids has added value with the CELL-DYN Sapphire

BACKGROUND

Conventional cytological examination has limited sensitivity for detecting tumor cells in serous body cavity effusions and therefore, adjuvant techniques are necessary for a reliable diagnosis. Flow cytometry has proven benefit in these circumstances. The aim of our study was to explore the feasibility of CELL-DYN Sapphire, an advanced hematology analyzer with flow cytometric capabilities, for detecting tumor cells in serous body fluids, using CD326 monoclonal antibodies, which are directed against the epithelial marker EpCAM.

METHODS

One hundred and five serous fluids (39 peritoneal and 66 pleural effusions) were analyzed by the CELL-DYN Sapphire using monoclonal antibody combinations CD3/CD19 and CD45/CD326. Of all samples a cytospin preparation was made and microscopically examined; the pathology findings served as a reference.

RESULTS

Using a threshold of 1% CD326+ cells, CELL-DYN Sapphire identified nine out of 12 cases with tumor cells in the serous effusions (sensitivity 75%), whereas routine cytology found eight cases (sensitivity 67%). The combination of immunophenotyping and cytology identified all 12 cases with tumor cells in the effusion fluid (sensitivity 100%). The specificities were 92% and 100%, respectively.

CONCLUSIONS

We demonstrated that it is feasible to run an immunophenotypic assay on CELL-DYN Sapphire for detecting tumor cells in serous body fluids. In addition, this study confirmed that a combination of conventional cytology and flow cytometry had a very high diagnostic yield in cases of carcinomatous effusions.

In vivo sex differences in leukotriene biosynthesis in zymosan-induced peritonitis

Leukotrienes (LTs) are 5-lipoxygenase (5-LO) metabolites which are implicated in sex-dependent inflammatory diseases (asthma, autoimmune diseases, etc.). We have recently reported sex differences in LT biosynthesis in in vitro models such as human whole blood, neutrophils and monocytes, due to down-regulation of 5-LO product formation by androgens. Here we present evidences for sex differences in LT synthesis and related inflammatory reactions in an in vivo model of inflammation (mouse zymosan-induced peritonitis). On the cellular level, differential 5-LO subcellular compartmentalization in peritoneal macrophages (PM) from male and female mice might be the basis for these differences. Sex differences in vascular permeability and neutrophil recruitment (cell number and myeloperoxidase activity) into peritoneal cavity were evident upon intraperitoneal zymosan injection, with more prominent responses in female mice. This was accompanied by higher levels of LTC4 and LTB4 in peritoneal exudates of female compared to male mice. Interestingly, LT peritoneal levels in orchidectomized mice were higher than in sham male mice. In accordance with the in vivo results, LT formation in stimulated PM from female mice was higher than in male PM, accompanied by alterations in 5-LO subcellular localization. The increased formation of LTC4 in incubations of PM from orchidectomized mice confirms a role of sex hormones. In conclusion, sex differences observed in LT biosynthesis during peritonitis in vivo may be related, at least in part, to a variant 5-LO localization in PM from male and female mice.

Exosomes are natural carriers of exogenous siRNA to human cells in vitro

BACKGROUND

Exosomes are nano-sized vesicles of endocytic origin that are involved in cell-to-cell communication including shuttle RNA, mainly mRNA and microRNA. As exosomes naturally carry RNA between cells, these particles might be useful in gene cancer therapy to deliver therapeutic short interfering RNA (siRNA) to the target cells. Despite the promise of RNA interference (RNAi) for use in therapy, several technical obstacles must be overcome. Exogenous siRNA is prone to degradation, has a limited ability to cross cell membranes and may induce an immune response. Naturally occurring RNA carriers, such as exosomes, might provide an untapped source of effective delivery strategies.

RESULTS

This study demonstrates that exosomes can deliver siRNA to recipient cells in vitro. The different strategies were used to introduce siRNAs into human exosomes of various origins. The delivery of fluorescently labeled siRNA via exosomes to cells was confirmed using confocal microscopy and flow cytometry. Two different siRNAs against RAD51 and RAD52 were used to transfect into the exosomes for therapeutic delivery into target cells. The exosome-delivered siRNAs were effective at causing post-transcriptional gene silencing in recipient cells. Moreover, the exosome-delivered siRNA against RAD51 was functional and caused the massive reproductive cell death of recipient cancer cells.

CONCLUSIONS

The results strongly suggest that exosomes effectively delivered the siRNA into the target cells. The therapeutic potential of exosome-mediated siRNA delivery was demonstrated in vitro by the strong knockdown of RAD51, a prospective therapeutic target for cancer cells. The results give an additional evidence of the ability to use human exosomes as vectors in cancer therapy, including RNAi-based gene therapy.

The Participation of Nitric Oxide in Peritoneal Exudate Cell Cytotoxicity of Mice byFusobacterium nucleatum

Previously we reported that mice infected recurrently with live Fusobacterium nucleatum(Fn) synthesize a significant amount of NO between 12 hr and 24 hr after Fn injection. Fn is a gram-negative rod periodontal pathogen. NO could not be induced by heat-killed Fn or in untreated mice. This NO, derived from the iNOS after infection of live Fn, was not involved in the Fn reduction because Fn clearance occurs within 6 hr. We investigated in this study whether this NO was involved in cytotoxicity in peritoneal exudate cells (PEC) in vivo. The mice were divided into two groups: those treated with live Fn (immune) and those left untreated (normal). PEC number, NO production, detection of apoptosis or death cells, and lactate dehydrogenase (LDH) release activity after injection of live Fn were compared in these groups. In the immune group, the increase of the total cell numbers caused by an increase in neutrophils, a significant NO production only after injection of live Fn at 24 hr and identification of iNOS positive macrophages were confirmed. The apoptotic rate was very low and did not increase at 24 hr in vivo. Therefore, apoptosis was seldom relevant to the NO. In the immune group, LDH activity was remarkable high at 24 hr, and dead cells and macrophages phagocytizing cell fragments increased at the same time. Pretreatment of L NMMA, an inhibitor of iNOS, suppressed LDH activity and cell death. Therefore, the NO derived from the iNOS is involved in the cytotoxicity. These results suggest that NO may contribute to the inflammatory response during Fn infection in periodontitis.

Meeting the challenge of ascites in ovarian cancer: new avenues for therapy and research

Malignant ascites presents a considerable clinical challenge to the management of ovarian cancer, but also provides a wealth of opportunities for translational research. The accessibility of ascitic fluid and its cellular components make it an excellent source of tumour tissue for the investigation of prognostic and predictive biomarkers, pharmacodynamic markers and for molecular profiling analysis. In this Opinion article, we discuss recent advances in our understanding of its pathophysiology, the development of new methods to characterize its molecular features and how these findings can be used to improve the treatment of malignant ascites, particularly in the context of ovarian cancer.

Purified graphene oxide dispersions lack in vitro cytotoxicity and in vivo pathogenicity

Prompted by the excitement from the description of single layer graphene, increased attention for potential applications in the biomedical field has been recently placed on graphene oxide (GO). Determination of the opportunities and limitations that GO offers in biomedicine are particularly prone to inaccuracies due to wide variability in the preparation methodologies of GO material in different laboratories, that results in significant variation in the purity of the material and the yield of the oxidation reactions, primarily the Hummers method used. Herein, the fabrication of highly pure, colloidally stable, and evenly dispersed GO in physiologically-relevant aqueous buffers in comparison to conventional GO is investigated. The purified GO material is thoroughly characterized by a battery of techniques, and is shown to consist of single layer GO sheets of lateral dimensions below 500 nm. The cytotoxic impact of the GO in vitro and its inflammation profile in vivo is investigated. The purified GO prepared and characterized here does not induce significant cytotoxic responses in vitro, or inflammation and granuloma formation in vivo following intraperitoneal injection. This is one of the initial steps towards determination of the safety risks associated with GO material that may be interacting with living tissue.

[Evaluation of the biological properties of a highly efficient tissue cell preservative]

OBJECTIVE

To evaluate the performance of a new highly efficient and environment-friendly tissue cell fixatives for preserving the morphologies and properties of pleural and peritoneal effusions.

METHODS

Fifty-six specimens of tissue cells from pleural and peritoneal effusions were preserved using the new preservative or 95% ethanol. HE staining and Western blotting were employed to detect the morphologies and protein expression levels of CK, CEA and P53 of the cells after fixation.

RESULTS

The new preservative well preserved the morphologies of the cells from the pleural and peritoneal effusions, and the nuclei and cytoplasm were intact with little debris. The conventional preservative (95% ethanol) caused noticeable structural damage of the tissue cells, especially the cytoplasm where obvious debris were seen after fixation. CK, CEA and P53 protein expression levels in the cells were 91%, 86% and 88% after fixation with the new preservative, significantly higher than those (46%, 38% and 31%, respectively) in cells fixed with 95% ethanol (P<0.05).

CONCLUSION

The new preservative is efficient and environment-friendly for preserving the morphologies as well as the proteins of tissue cells from pleural and peritoneal effusions well, demonstrating its potential in tissue cell fixation and preservation.

Characteristics of ascites in patients with pregnancy-specific liver diseases

BACKGROUND & AIMS

The characteristics of ascites in patients with pregnancy-specific liver disease (PsLD), which comprise acute fatty liver of pregnancy, hemolysis, increased levels of liver enzymes, low platelet syndrome, and preeclampsia-associated liver dysfunction, are unknown. We evaluated the cellular and biochemical characteristics, and model for end-stage liver disease scores, in patients with PsLD.

METHODS

We evaluated 46 consecutive patients with PsLD for the presence of ascites. We assessed cellular and biochemical characteristics of the ascites fluid from these patients.

RESULTS

Ascites was observed in 35 of 46 patients with PsLD (76%). In 25 patients tested (71.4%), the ascites fluid had low levels of albumin (<0.2 g/dL) and protein (<1 g/dL) and high serum ascites albumin gradients, indicating portal hypertension. Spontaneous bacterial peritonitis was observed in 48% of patients tested and was not associated with mortality. Patients with ascites had significantly low serum levels of protein and albumin (P < .001). Model for end-stage liver disease scores did not differ between patients with or without ascites (32 vs 27; P = .1).

CONCLUSIONS

Ascites occur in 76% of women with PsLD, is transient, and has characteristics of portal hypertension, based on high serum ascites albumin gradients. Almost half of patients with PsLD develop spontaneous bacterial peritonitis, which does not affect survival.

[Diagnostic assessment of peritoneal fluid cytology in horses with abdominal neoplasia]

OBJECTIVE

To evaluate the diagnostic value of peritoneal fluid (PF) cytology for clinical diagnosis of abdominal neoplasia in horses.

MATERIAL AND METHODS

Ten horses with histopathologically confirmed abdominal neoplasia, in which a PF analysis was performed, were included in this retrospective study. PF was analyzed for total protein concentration and a nucleated cell count was performed. Using cytological criteria of malignancy, the PF samples were evaluated regarding their probability of malignancy.

RESULTS

Cytologic classification of cells according to criteria of malignancy allowed a positive cytologic diagnosis of neoplasia in 5 out of 10 peritoneal fluid samples. Malignant lymphoma was the most commonly diagnosed neoplasia (3/10) and could be identified by cytology in 2/3 cases. In 1/2 horses with plasma cell myeloma neoplastic cells were similarly found. Malignant melanoma (2/10) was diagnosed using cytology in one case (presence of melanin-containing cells). Cytological diagnosis of malignant neoplasia was established in the only horse with gastric squamous cell carcinoma, but the morphology of the identified tumour cells did not allow a specific diagnosis. Thus, a definitive diagnosis was achieved in 4/5 horses with proven abdominal neoplasia. The horses with adenocarcinoma (1/10) and haemangiosarcoma (1/10) had no evidence of neoplasia based on cytological findings. No relationship between total protein concentration or the nucleated cell count with the histolopathological diagnosis of abdominal neoplasia was found. Abnormal mitotic figures were considered of greater diagnostic value than the overall mitotic rate.

CONCLUSION

The implementation of nuclear criteria of malignancy in the cytologic evaluation of PF samples allows the identification of neoplastic cells to an acceptable degree. For this purpose, the knowledge of the highly variable morphological features of mesothelial cells is essential. The absence of malignant cells does not rule out abdominal neoplasia.

CLINICAL RELEVANCE

PF cytology should be considered as a valuable, minimally invasive, simple, and rapid diagnostic technique in horses with suspected abdominal neoplasia.

Isolation of human and mouse neutrophils ex vivo and in vitro

Neutrophils are one of main cellular elements of innate immune system that act as the first line of host defense against invasion by microorganisms. Neutrophils phagocytose and kill microbes through production of toxins such as hydrogen peroxide, superoxide anion, and nitric oxide. Recent studies have demonstrated a new strategy-so-called neutrophil extracellular traps (NETs) that are able to kill bacteria and fungi in vivo and in vitro (Brinkmann et al., Science 303:1532-1535, 2004; Wartha and Henriques-Normark, Sci Signal 1:pe25, 2008). Neutrophils are, therefore, always a major focus of investigation for scientists all over the world. Isolation of neutrophils from either human beings or animals such as mice is a very common first step for researchers to start their investigations on innate immunity to microbes. Fortunately, there are nowadays many methods available to obtain neutrophils from peripheral blood, bone marrow, and cell cultures. However, researchers still encounter technical problems in terms of purification, viability, and recovery. In this chapter, different approaches to the methodology of the isolation of neutrophils are described.

The bradykinin B1 receptor antagonist R-954 inhibits Ehrlich tumor growth in rodents

The present study investigated the effects of a new bradykinin B(1) receptor antagonist, R-954, on the development of Ehrlich ascitic tumor (EAT) induced by the intraperitoneal inoculation of EAT cells in mice and the formation of a solid tumor by the subcutaneous injection of the cells in rat paw. The development of the tumor was associated with an increase in mouse total cell counts in bone marrow (10.8-fold), ascitic fluid (14.6-fold), and blood (12.6-fold). R-954 (2mg/kg, s.c.) significantly reduced the ascitic fluid volume (63.7%) and the mouse weight gain (30.5%) after 10 consecutive days of treatment. The B(1) antagonist as well as the anti-neoplasic drug vincristine also significantly inhibited the increase in total cell count in bone marrow, ascitic fluid, and blood. R-954 reduced significantly the total protein extravasation (57.3%), the production of nitric oxide (56%), PGE(2) production (82%), and TNFα release (85.7%) in mice peritoneal cavity whereas vincristine reduced the release of these inflammatory mediators by 84-94%. The increase in paw edema after intraplantar injection of EAT cells was reduced by approximately 52% by either R-954 or vincristine treatment. In conclusion, this study presents for the first time the antitumoral activity of a new bradykinin B(1) receptor antagonist on ascitic and solid tumors induced by Ehrlich cell inoculation in mice and rats.

Signet ring cells in ascitic fluid -- a diagnostic dilemma

Traditional teaching is that signet ring cells are the hall-mark of ovarian metastatic tumours. Paracentesis done for therapeutic purpose showed these cells and momentarily misled us. Other differentiating data are important in the correct management of cases with signet ring cells found in either ascitic fluid or on histopathologic examination.

Effects of perfluorooctane sulfonate (PFOS) exposure on markers of inflammation in female B6C3F1 mice

Perfluorooctane sulfonate (PFOS; 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-1-octanesulfonic acid) has been reported to alter humoral immune functions, but inflammatory processes following PFOS exposure have not been fully characterized. Therefore, the current study, assessed TNF-α and IL-6 concentrations in serum and peritoneal lavage fluid, numbers of splenoctyes expressing intracellular TNF-α, IL-6, IL-10 or IL-1, and ex vivo TNF-α and IL-6 production by peritoneal macrophages following either in vivo or in vitro LPS exposure. Adult female B6C3F1 mice were exposed orally for 28 days to 0, 1, 3, or 300 mg PFOS/kg total administered dose [TAD] (e.g., 0, 0.0331, 0.0993 or 9.93 mg/kg/day). Body and spleen masses were significantly reduced in the highest PFOS treatment group compared to the control group, whereas liver mass was significantly increased. Serum TNF-α levels were significantly decreased following exposure to 1 mg PFOS/kg TAD as compared to controls, while serum IL-6 levels were increased. IL-6 concentrations in peritoneal lavage fluid decreased with increasing dose. PFOS treatment did not alter numbers of splenocytes expressing intracellular levels of TNF-α, IL-10 or IL-1. Numbers of splenocytes expressing intracellular levels of IL-6 were significantly decreased in the 3 mg/kg treatment as compared to controls. Overall, these data suggest that PFOS exposure can alter some inflammatory processes, which could potentially lead to misdirected inflammatory responses.

[Spontaneous bacterial peritonitis: scientific and practical achievements and prospects]

We presented the results of our research in comparison with the literature on the etiology, pathogenesis and diagnosis of spontaneous bacterial peritonitis (SBP) at liver cirrhosis (LC), complicated by ascites. Based on these data, was proposed a classification of SBP. Were identified criteria for early diagnosis of SBP on the basis of clinical manifestations of bacterial peritonitis, systemic inflammatory response, results of studies of ascitic fluid (AF) using gas chromatography-mass spectrometry (GC-MS). In accordance with the proposed criteria was proposed a scheme for the diagnosis, treatment and prevention of STDs. Presents data on the effectiveness of therapy and prevention of SBP. Denote the potential major long-term trends in the treatment of SBP in cirrhosis.

[Spontaneous bacterial peritonitis and systemic inflammatory reaction in hepatic cirrhosis patients]

AIM

To develop criteria of early diagnosis of spontaneous bacterial peritonitis (SBP) in hepatic cirrhosis (HC).

MATERIAL AND METHODS

Clinical symptoms of SBP including systemic inflammatory reaction were analysed in 286 patients. The count of polymorphonuclear neutrophils (PNL) in ascitic liquid (AL), microbiological study of the blood and AL were made. Ultrasound investigation assessed acoustic homogeneity of AL. Blood serum (BS) and AL were tested for cytokines content: interleukine-1beta, TNF-alpha, interleukine-4, transforming growth factor beta, C-reactive protein. Gas chromatography--mass spectrometry (GC-MC) estimated quantity and quality of chemical components--markers of potential infectious agents of AL.

RESULTS

Three groups of patients were identified: group A (a classic SBP) consisted of 23 patients with clinical symptoms of SBP and PNL content > 0.25 x 10(9)/l; group B (control) consisted of 19 patients free of SBP symptoms and PNL content < 0.25 x 10(9)/l; group C (patients at risk)--18 patients with SBP symptoms and PNL content < 0.25 x 10(9)/l. Cultural test of AL was negative in all the groups. Symptoms of SIR occurred equally often in groups A and C. CRP in AL was higher (23.8 +/- 4.3 g/l) in group A than in group B (p < 0.05). CRP concentration (8.6 +/- 2.1 g/l) was higher in group C than in group B (p < 0.05). Changes in cytokine composition were similar in groups A and C. The number of chemical bacterial markers was higher in groups A and C (p < 0.005).

CONCLUSION

Patients of group C with SIR, elevated CRP, changed cytokine status, high content of chemical markers of AL infection by GC-MC are at high risk of SBP. Such patients need adequate and early antibacterial therapy.

[Role of a latent soluble TNF receptor type I (hsTNFRI) fusion protein in targeted treatment of endometriosis]

OBJECTIVE

To construct a latent human soluble tumor necrosis factor receptor I (hsTNFRI) using the latency associated protein (LAP) of transforming growth factor-beta1 (TGF-beta1) fused via a matrix metalloproteinase (MMP) cleavage site to hsTNFRI so as to detect the latent biological activity of LAP-MMP-hsTNFRI fusion protein.

METHODS

A double-stranded deoxyoligonucleotide coding for MMP cleavage site was cloned into plasmid pcDNA3.1. LAP and hsTNFRI cDNA were then inserted into both two sides of MMP cleavage site. After being transferred by LAP-MMP-hsTNFRI fusion gene with liposome, the expression of fusion protein in COS-7 cells was detected by RT-PCR and Western blot. The inhibitory effect of fusion protein upon cytotoxicity of TNF-alpha was detected by methyl thiazolyl tetrazolium (MTT) assay before and after the fusion protein incubated in MMP or peritoneal fluid from endometriosis patients.

RESULTS

The recombinant plasmid LAP-MMP-hsTNFRI-pcDNA3.1 was constructed successfully and was expressed effectively in COS-7 cells. The MTT assay showed that there was no difference in the mortality rate of L929 cells between LAP-MMP-hsTNFRI-pcDNA3.1 and empty vector transfection groups (P > 0.05). The mortality rates of L929 cells with 800 ng/L TNF-alpha in LAP-MMP-hsTNFRI-pcDNA3.1 transfection group after incubation with MMP or peritoneal fluid from endometriosis patients were (44.5 +/- 2.4)% and (33.8 +/- 1.9)% respectively. And it was lower than the pre-incubation period (58.1 +/- 2.4)% (P < 0.05).

CONCLUSION

The biological activity of LAP-MMP-hsTNFRI fusion protein can be made latent by LAP and activated by peritoneal fluid from endometriosis. Thus a new method has been provided for a targeted therapy of endometriosis.

A simple method to measure NK cell cytotoxicity in vivo

Natural killer (NK) cells were discovered in the 1970 s and named after their naturally occurring cytotoxic activity against tumor cells. It has recently become clear that NK cells are not just killers and that malignancy is unlikely to be the selective pressure driving the evolution of NK cells. Indeed, NK cells secrete a host of cytokines and chemokines that contribute to tissue remodeling at the feto-maternal interface and to both innate and adaptive immunity during infection. Moreover, in certain conditions, they cannot deliver functions cell autonomously, as they require priming from other cells, namely dendritic cells. Nevertheless, natural cytotoxicity is still considered an important parameter used to evaluate NK cell biology, both in the clinic and in the research lab. In this chapter we describe a simple method to quantify spontaneous NK cell cytotoxicity in vivo.

[A rare cause of peritoneal dialysis-related peritonitis: Haemophilus influenzae]

Haemophilus influenzae is a rarely reported cause of peritonitis in chronic ambulatory peritoneal dialysis (CAPD) patients. In this report, a peritonitis case due to H. influenzae in a 32-years-old female patient with end-stage renal failure receiving CAPD for 7 years, has been reported. The patient was admitted to our clinic with the complaints of nausea, vomiting, abdominal pain, and cloudy dialysate. She had diffuse abdominal tenderness, however, other systems and peritoneal catheter exit site were found to be normal in physical examination. White blood cell (WBC) count in peritoneal fluid was 1.500/mm3 with 90% neutrophils. Gram stain of the peritoneal fluid yielded moderate number of polymorphonuclear leucocytes but no microorganism. Empirical antibiotic therapy with vancomycin and amikacin was initiated intraperitoneally. Peritoneal fluid and blood cultures were performed using BacT/ALERT (bioMerieux, NC, USA) blood culture system. Although no growth was detected in the blood sample at the end of the 5 days, growth was observed in the peritoneal sample within 48 hours. Gram staining of the positive bottle revealed gram-negative coccobacilli. At the end of an overnight incubation period, the colonies, which grew on chocolate agar, were identified as H. influenzae by using API NH system (bioMerieux, NC, USA). The isolate was found to be beta-lactamase-negative. The antibiotic regimen was switched to cephazoline 2 g/day intraperitoneally. The patient rapidly recovered and the WBC count of the peritoneal effluent decreased to 70/mm3. The therapy was continued for 21 days and she was discharged. The peritoneal catheter was not removed. During 7 months after the therapy, peritonitis did not recur. In conclusion, H. influenzae should be kept in mind as a cause of peritonitis in CAPD patients even though it is an unusual agent and the infection may be successfully treated with intraperitoneal antibiotics without removal of peritoneal dialysis catheter.

Chronic ovarian pregnancy mimicking an ovarian tumor diagnosed by peritoneal washing cytology: a case report

BACKGROUND

Chronic ectopic pregnancy is an enigma. The clinical presentation can be mild, with absent or subtle symptoms. Ovarian pregnancy usually ends with rupture. We report the first case of unruptured chronic ovarian pregnancy that was initially diagnosed by peritoneal washing cytology.

CASE

A 35-year-old woman suffered from low abdominal pain during the presumed menstrual period for 6 months. Abdominal computed tomography revealed a huge cystic mass with intralesional hematoma and soft tissue components located in the pelvic cavity. Mild right hydronephrosis caused by tumor obstruction of the right ureter were noted. Right ovarian cancer was suspected. Peritoneal washing cytology revealed both cytotrophoblasts and syncytiotrophoblasts. Patient received enucleation of the right ovary. Microscopically, the ovarian mass exhibited extensive hemorrhage and necrosis, embedding degenerated chorionic villi.

CONCLUSION

When a patient experiences low abdominal pain during a menstrual period, the possibility of ectopic pregnancy should be considered in addition to possible endometriosis. Ovarian or other abdominal pregnancies, even untruptured, may be discriminated from other lesions in cases of abdominal pain by peritoneal washing cytology.