Fractionated brain X-irradiation profoundly reduces hippocampal immature neuron numbers without affecting spontaneous behavior in mice

Whole brain radiotherapy (WBRT) is used to improve tumor control in patients with primary brain tumors, or brain metastasis from various primary tumors to improve tumor control. However, WBRT can lead to cognitive decline in patients. We assessed whether fractionated WBRT (fWBRT) affects spontaneous behavior of mice in automated home cages and cognition (spatial memory) using the Barnes maze. Male C57Bl/6j mice received bi-lateral fWBRT at a dosage of 4 Gy/day on 5 consecutive days. In line with previous reports, immunohistochemical analysis of doublecortin positive cells in the dentate gyrus showed a profound reduction in immature neurons 4 weeks after fWBRT. Surprisingly, spontaneous behavior as measured in automated home cages was not affected. Moreover, learning and memory measured with Barnes maze, was also not affected 4-6 weeks after fWBRT. At 10-11 weeks after fWBRT a significant difference in escape latency during the learning phase, but not in the probe test of the Barnes maze was observed. In conclusion, although we confirmed the serious adverse effect of fWBRT on neurogenesis 4 weeks after fWBRT, we did not find similar profound effects on spontaneous behavior in the automated home cage nor on learning abilities as measured by the Barnes maze. The relationship between the neurobiological effects of fWBRT and cognition seems more complex than often assumed and the choice of animal model, cognitive tasks, neurobiological parameters, and experimental set-up might be important factors in these types of experiments.

Learning Curves in Open, Laparoscopic, and Robotic Pancreatic Surgery: A Systematic Review and Proposal of a Standardization

Objective

To depict and analyze learning curves for open, laparoscopic, and robotic pancreatoduodenectomy (PD) and distal pancreatectomy (DP).

Background

Formal training is recommended for safe introduction of pancreatic surgery but definitions of learning curves vary and have not been standardized.

Methods

A systematic search on PubMed, Web of Science, and CENTRAL databases identified studies on learning curves in pancreatic surgery. Primary outcome was the number needed to reach the learning curve as defined by the included studies. Secondary outcomes included endpoints defining learning curves, methods of analysis (statistical/arbitrary), and classification of learning phases.

Results

Out of 1115 articles, 66 studies with 14,206 patients were included. Thirty-five studies (53%) based the learning curve analysis on statistical calculations. Most often used parameters to define learning curves were operative time (n = 51), blood loss (n = 17), and complications (n = 10). The number of procedures to surpass a first phase of learning curve was 30 (20-50) for open PD, 39 (11-60) for laparoscopic PD, 25 (8-100) for robotic PD (P = 0.521), 16 (3-17) for laparoscopic DP, and 15 (5-37) for robotic DP (P = 0.914). In a three-phase model, intraoperative parameters improved earlier (first to second phase: operating time -15%, blood loss -29%) whereas postoperative parameters improved later (second to third phase: complications -46%, postoperative pancreatic fistula -48%). Studies with higher sample sizes showed higher numbers of procedures needed to overcome the learning curve (rho = 0.64, P < 0.001).

Conclusions

This study summarizes learning curves for open-, laparoscopic-, and robotic pancreatic surgery with different definitions, analysis methods, and confounding factors. A standardized reporting of learning curves and definition of phases (competency, proficiency, mastery) is desirable and proposed.

Radiological management of postoperative lymphorrhea

PURPOSE

Postoperative lymphorrhea can occur after different surgical procedures and may prolong the hospital stay due to the need for specific treatment. In this work, the therapeutic significance of the radiological management of postoperative lymphorrhea was assessed and illustrated.

METHOD

A standardized search of the literature was performed in PubMed applying the Medical Subject Headings (MeSH) term "lymphangiography." For the review, the inclusion criterion was "studies with original data on Lipiodol-based Conventional Lymphangiography (CL) with subsequent Percutaneous Lymphatic Intervention (PLI)." Different exclusion criteria were defined (e.g., studies with <15 patients). The collected data comprised of clinical background and indications, procedural aspects and types of PLI, and outcomes. In the form of a pictorial essay, each author illustrated a clinical case with CL and/or PLI.

RESULTS

Seven studies (corresponding to evidence level 4 [Oxford Centre for Evidence-Based Medicine]) accounting for 196 patients were included in the synthesis and analysis of data. Preceding surgery resulting in postoperative lymphorrhea included different surgical procedures such as extended oncologic surgery or vascular surgery. Central (e.g., chylothorax) and peripheral (e.g., lymphocele) types of postoperative lymphorrhea with a drainage volume of 100-4000 ml/day underwent CL with subsequent PLI. The intervals between "preceding surgery and CL" and between "CL and PLI" were 2-330 days and 0-5 days, respectively. CL was performed before PLI to visualize the lymphatic pathology (e.g., leakage point or inflow lymph ducts), applying fluoroscopy, radiography, and/or computed tomography (CT). In total, seven different types of PLI were identified: (1) thoracic duct (or thoracic inflow lymph duct) embolization, (2) thoracic duct (or thoracic inflow lymph duct) maceration, (3) leakage point direct embolization, (4) inflow lymph node interstitial embolization, (5) inflow lymph duct (other than thoracic) embolization, (6) inflow lymph duct (other than thoracic) maceration, and (7) transvenous retrograde lymph duct embolization. CL-associated and PLI-associated technical success rates were 97-100% and 89-100%, respectively. The clinical success rate of CL and PLI was 73-95%. CL-associated and PLI-associated major complication rates were 0-3% and 0-5%, respectively. The combined CL- and PLI-associated 30-day mortality rate was 0%, and the overall mortality rate was 3% (corresponding to six patients). In the pictorial essay, the spectrum of CL and/or PLI was illustrated.

CONCLUSION

The radiological management of postoperative lymphorrhea is feasible, safe, and effective. Standardized radiological treatments embedded in an interdisciplinary concept are a step towards improving outcomes.

Radiological evaluation of pancreatic cancer: What is the significance of arterial encasement >180° after neoadjuvant treatment?

PURPOSE

This study aimed to evaluate contrast-enhanced computed tomography (CE-CT) features for prediction of arterial tumor invasion in pancreatic cancer (PDAC) patients in the event of arterial encasement >180° after neoadjuvant (radio-)chemotherapy (NAT).

METHODS

Seventy PDAC patients with seventy-five arteries showing encasement >180° after completion of NAT were analyzed. All patients underwent surgical exploration with either tumor resection including arterial resection, periadventitial dissection (arterial divestment) or confirmation of locally irresectable disease. CE-CT scans were assessed regarding tumor extent and artery-specific imaging features. The results were analyzed on a per-artery basis. Based on the intraoperative and histopathological findings, encased arteries were classified as either invaded or non-invaded.

RESULTS

Eighteen radiologically encased arteries were resected; of these, nine had pathologic evidence for tumor invasion. In 42 encased arteries, the tumor could be removed by arterial divestment. In 13 patients with 15 encased arteries, the tumor was deemed technically irresectable. Median tumor size, length of solid soft tissue contact, and degree of circumferential contiguity by solid soft tissue along the artery in CE-CT were significantly lower in the non-invaded than in the invaded artery group (p ≤ 0.017). Imaging features showed moderate accuracies for prediction of arterial invasion (≤72.0 %). The thresholds ≤26 mm for post-NAT solid soft tissue contact and ≤270° for circumferential contiguity by solid soft tissue had high negative predictive values (≥87.5 %).

CONCLUSION

Although post-NAT prediction of arterial invasion remains difficult, arteries with ≤270° contiguity by soft tissue and arteries with ≤26 mm length of solid soft tissue contact are unlikely to be invaded, with possible implications for surgical planning.

Percutaneous afferent lymphatic vessel sclerotherapy for postoperative lymphatic leakage after previous ineffective therapeutic transpedal lymphangiography

BACKGROUND

To demonstrate the efficacy of percutaneous computed tomography (CT)-guided afferent lymphatic vessel sclerotherapy (ALVS) in the treatment of postoperative lymphatic leakage (LL) after ineffective therapeutic transpedal lymphangiography (TL).

METHODS

A retrospective review in this institute involving 201 patients was conducted from May 2011 to September 2018. Patients diagnosed with postoperative LL undergoing ineffective therapeutical TL before the performance of percutaneous CT-guided ALVS were involved. Technical success and clinical success of TL and ALVS were established. The technical success and efficacy of ALVS in the treatment of postoperative LL after ineffective therapeutic TL were assessed. The clinical success rate of ALVS is also assessed, and the complications are reviewed.

RESULTS

In total, nine patients were involved including three patients (33.3%) presented with chylothorax, three patients (33.3%) presented with inguinal lymphatic fistula/lymphocele, and three patients (33.3%) presented with lymphatic fistula in the thigh; 27 ± 18 days (mean ± standard deviation) after surgery, therapeutic TL was successfully performed and showed definite afferent lymphatic vessel and leakage site in all the patients. Due to clinical failure after TLs, the following ALVS was performed with a mean interval of 12 ± 8 days after TL. The technical success rate was 9/9 (100.0%, 95% confidence interval [CI] 63.1-100.0%). An average of 2.7 ± 1.3 mL 95% ethanol as sclerosant agent was injected during the procedure. The clinical success was observed in 8 of the 9 patients (88.9%, 95% CI 51.8-99.7%) with a time between ALVS and the LL cure of 8 ± 6 days. No complications were reported.

CONCLUSIONS

Our results showed the role of percutaneous CT-guided ALVS as a safe, feasible, and effective salvage treatment for postoperative LL after ineffective TL.

The roles of iodized oil-based lymphangiography and post-lymphangiographic computed tomography for specific lymphatic intervention planning in patients with postoperative lymphatic fistula: a literature review and case series

In the management of patients with postoperative lymphatic fistula (LF) in different locations, iodized oil-based lymphangiography (LAG) from trans-pedal or intranodal route is an established diagnostic approach with the potential to plan further interventional treatments. However, specific lymphatic interventions are indicated depending on different locations and morphologies of the LF. After a systematic literature review, four types of interventions can be considered, including direct leakage embolization/sclerotherapy (DLE/DLS), percutaneous afferent lymphatic vessel embolization (ALVE), percutaneous afferent lymphatic vessels disruption/sclerotherapy (ALVD/ALVS), and trans-afferent nodal embolization (TNE). In the iodized oil-based LAG, three potential lymphatic targets including confined leakage, definite afferent LVs, and definite closest afferent LNs should be comprehensively assessed. For optimal prospective treatment planning for LF, iodized oil-based post-lymphangiographic computed tomography (post-LAG CT) is a useful complement to the conventional iodized oil-based LAG, which can be performed easily after LAG. This review article summarized the current evidence of the specific lymphatic interventions in patients with postoperative LF and explored the potential benefits of post-LAG CT in the intervention planning from a case series.

[Perioperative fluid management in major abdominal surgery]

Intravascular fluid administration belongs to the cornerstones of perioperative treatment with a substantial impact on surgical outcome especially with respect to major abdominal surgery. By avoidance of hypovolemia and hypervolemia, adequate perioperative fluid management significantly contributes to the reduction of insufficient tissue perfusion as a determinant of postoperative morbidity and mortality. The effective use of intravascular fluids requires detailed knowledge of the substances as well as measures to guide fluid therapy. Fluid management already starts preoperatively and should be continued in the postoperative setting (recovery room, peripheral ward) considering a patient-adjusted and surgery-adjusted hemodynamic monitoring. Communication between all team members participating in perioperative care is essential to optimize fluid management.

Comparison of different types of landfill leachate treatments by employment of nontarget screening to identify residual refractory organics and principal component analysis

Three different chemical oxidation processes were investigated in terms of their capability to degrade organic chemical components of real mature landfill-leachate in combination with biological treatment run in a Sequencing Batch Biofilter Granular Reactor (SBBGR). H₂O₂, H₂O₂ + UV and O₃ were integrated with SBBGR and respective effluents were analyzed and compared with the effluent obtained from biological SBBGR treatment alone. In agreement with their respective oxidative power, conventional bulk parameters (residual COD, TOC, N_tot, TSS) determined from the resulting effluents evidenced the following efficacy ranking for degradation: SBBGR/O₃ > SBBGR/UV + H₂O₂ > SBBGR/H₂O₂ > SBBGR. A more detailed characterization of the organic compounds was subsequently carried out for the four treated streams. For this, effluents were first subjected to a sample preparation step, allowing for a classification in terms of acidic, basic, strongly acidic and strongly basic compounds, and finally to analysis by liquid chromatography/high resolution mass spectrometry (LC/HR-MS). This classification, combined with further data post-processing (non-target screening, Venn Diagram, tri-dimensional plot and Principal Component Analysis), evidenced that the SBBGR/H₂O₂ process is comparable to the pure biological oxidation. In contrast, SBBGR/O₃ and SBBGR/UV + H₂O₂ not only resulted in a very different residual composition as compared to SBBGR and SBBGR/H₂O₂, but also differ significantly from each other. In fact, and despite of the SBBGR/O₃ being the most efficient process, this treatment remained chemically more similar to SBBGR/H₂O₂ than to SBBGR/UV + H₂O₂. This finding may be attributable to different mechanism of degradation involved with the use of UV radiation. Apart from these treatment differences, a series of recalcitrant compounds was determined in all of the four treatments and partly identified as hetero-poly-aromatic species (humic acids-like species).

Constitutive loss and acute pharmacological manipulation of ErbB4 signaling do not affect attention and inhibitory control in mice

The receptor tyrosine kinase ErbB4 and its ligand trophic factors of the neuregulin (NRG) family have been associated with schizophrenia and other mental disorders in human genetic studies. In vivo studies in mice have shown how abnormal Nrg-ErbB4 signaling leads to deviant behaviors relevant to distinct aspects of schizophrenia, including hyperactivity, sensory gating deficits, working and spatial memory deficits and impaired social behavior. However, so far little is known on the role of ErbB4 in attention and inhibitory control, two aspects of executive functions that are impaired in schizophrenia. Here we investigated the effects of constitutive loss of ErbB4 in the central nervous system of mice on performance in a 5-choice serial reaction time task (5CSRTT) assessing attention and inhibitory control. In this task, ErbB4^-/- mice did not show deficits in various parameters of attention, and premature responses as measure of inhibitory control. Nonetheless, ErbB4^-/- mice recapitulated a specific set of behavioral phenotypes associated with schizophrenia, including a deficit in spatial learning and memory in the Barnes Maze and in contextual fear learning, and a trend for a deficit in sensorimotor gating. Furthermore, we investigated the effect of acute pharmacological inhibition of ErbB tyrosine kinase receptor using the pan-ErbB kinase inhibitor JNJ-28871063 (JNJ), in an automated version of the 5CSRTT. JNJ did not affect attention and inhibitory control. In conclusion, our data suggest no direct involvement of a classical Nrg-ErbB4 pathway in attention and inhibitory control in mice, while it confirms the involvement of this pathway in other domains relevant to schizophrenia.

Cognitive flexibility deficits in a mouse model for the absence of full-length dystrophin

Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disorder, caused by mutations in the DMD gene and the resulting lack of dystrophin. The DMD gene has seven promoters, giving rise to multiple full-length and shorter isoforms. Besides the expression of dystrophin in muscles, the majority of dystrophin isoforms is expressed in brain and dystrophinopathy can lead to cognitive deficits, including intellectual impairments and deficits in executive function. In contrast to the muscle pathology, the impact of the lack of dystrophin on the brain is not very well studied. Here, we study the behavioral consequences of a lack of full-length dystrophin isoforms in mdx mice, particularly with regard to domains of executive functions and anxiety. We observed a deficit in cognitive flexibility in mdx mice in the absence of motor dysfunction or general learning impairments using two independent behavioral tests. In addition, increased anxiety was observed, but its expression depended on the context. Overall, these results suggest that the absence of full-length dystrophin in mice has specific behavioral effects that compare well to deficits observed in DMD patients.

Neurobiological changes by cytotoxic agents in mice

Cognitive deficit is a frequently reported side-effect of adjuvant chemotherapy. A large number of animal studies has been performed to examine the neurobiological mechanisms underlying this phenomenon, however, definite conclusions from these studies are restricted due to differences in experimental set-up. We systematically investigated the effects of 6 cytotoxic agents on various neurobiological parameters. C57Bl/6J mice were treated with cyclophosphamide, docetaxel, doxorubicin, 5-fluorouracil, methotrexate, or topotecan. The animals were sacrificed 3 or 15 weeks after treatment and the effect on neurogenesis, blood vessel density, and neuroinflammation was analyzed using immunohistochemistry. None of the cytostatic agents tested affected neurogenesis (cell survival or cell proliferation). Blood vessel density was increased in the hippocampus and prefrontal cortex 3 weeks after treatment with docetaxel and doxorubicin compared with control animals. A decrease in the number of microglial cells was observed in the prefrontal cortex after treatment with cyclophosphamide, docetaxel, 5-FU, and topotecan compared with control mice. The observed decrease in microglia cells is indicative of inflammation that occurred after treatment. Overall, the magnitude of the effects was relatively modest. Therefore, we conducted a similar study with topotecan in Abcg2;Abcb1a/b knock out and wildtype FVB mice. Animals were sacrificed 3 weeks after treatment and no notable effect was seen in hippocampal cell differentiation (DCX), microglia activation, or blood vessel density. Perhaps the FVB strain is more resistant to the neurotoxic effects of topotecan which makes this not the correct model to study the mechanism of chemotherapy-induced cognitive impairment.

Potential role of Th17 cells in the pathogenesis of type 2 autoimmune pancreatitis

Th17 cells have been shown to play an important role in the pathogenesis of a variety of autoimmune diseases. The aim of this study was to investigate the potential role of Th17 cells in autoimmune pancreatitis (AIP). Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine gene expression of the signature cytokines of Th17 cells IL-17A and IL-21 and of the Th17 lineage-specific transcription factor retinoic acid receptor-related orphan receptor C (RORC) in human tissue specimens of AIP, classical chronic pancreatitis (CP), and normal pancreas (NP). Infiltrating immune cells were characterized by immunohistochemistry (IHC). Gene expression of IL-17A, IL-21, and RORC were found to be significantly increased in AIP. Accordingly, the number of Th17 cells was significantly increased in AIP compared to NP or CP. Both gene expression analysis and IHC revealed a clear difference between type 1 and 2 AIP. In the periductal compartment of type 2 AIP, which is characterized by granulocytic epithelial lesions (GELs), the number of infiltrating Th17 cells and neutrophilic granulocytes was significantly increased compared to type 1 AIP. Our data suggest that Th17 cells play a role in the pathogenesis of AIP, in particular of type 2 AIP. Cross-talk between Th17 cells and neutrophilic granulocytes mediated via IL-17A may be a potential mechanism by which neutrophils are recruited to the duct and acinar cells with subsequent destruction, a process that is pathognomonic for type 2 AIP.

Functional characterization of the PCLO p.Ser4814Ala variant associated with major depressive disorder reveals cellular but not behavioral differences

Genome-wide association studies have suggested a role for a genetic variation in the presynaptic gene PCLO in major depressive disorder (MDD). As with many complex traits, the PCLO variant has a small contribution to the overall heritability and the association does not always replicate. One variant (rs2522833, p.Ser4814Ala) is of particular interest given that it is a common, nonsynonymous exon variant near a calcium-sensing part of PCLO. It has been suggested that the molecular effects of such variations penetrate to a variable extent in the population due to phenotypic and genotypic heterogeneity at the population level. More robust effects may be exposed by studying such variations in isolation, in a more homogeneous context. We tested this idea by modeling PCLO variation in a mouse knock-in model expressing the Pclo(SA)(/)(SA) variant. In the highly homogeneous background of inbred mice, two functional effects of the SA-variation were observed at the cellular level: increased synaptic Piccolo levels, and 30% increased excitatory synaptic transmission in cultured neurons. Other aspects of Piccolo function were unaltered: calcium-dependent phospholipid binding, synapse formation in vitro, and synaptic accumulation of synaptic vesicles. Moreover, anxiety, cognition and depressive-like behavior were normal in Pclo(SA)(/)(SA) mice. We conclude that the PCLO p.Ser4814Ala missense variant produces mild cellular phenotypes, which do not translate into behavioral phenotypes. We propose a model explaining how (subtle) cellular phenotypes do not penetrate to the mouse behavioral level but, due to genetic and phenotypic heterogeneity and non-linearity, can produce association signals in human population studies.

Cognitive impact of cytotoxic agents in mice

RATIONALE AND OBJECTIVES

Adjuvant chemotherapy is associated with changes in cognition in a subgroup of cancer patients. Chemotherapy is generally given as a combination of cytotoxic agents, which makes it hard to define the agent responsible for these observed changes. Literature on animal experiments has been difficult to interpret due to variance in experimental setup.

METHODS

We examined the effects of cytotoxic agents administered separately on various cognitive measures in a standardized animal model. Male C57Bl/6 mice received cyclophosphamide, docetaxel, doxorubicin, 5-fluorouracil, methotrexate, or topotecan. These agents represent different compound classes based on their working mechanism and are frequently prescribed in the clinic. A control group received saline. Behavioral testing started 2 or 15 weeks after treatment and included testing general measures of behavior and cognitive task performance: spontaneous behavior in an automated home cage, open field, novel location recognition (NLR), novel object recognition (NOR), Barnes maze, contextual fear conditioning, and a simple choice reaction time task (SCRTT).

RESULTS

Cyclophosphamide, docetaxel, and doxorubicin administration affected spontaneous activity in the automated home cage. All cytotoxic agents affected memory (NLR and/or NOR). Spatial memory measured in the Barnes maze was affected after administration with doxorubicin, 5-fluorouracil, and topotecan. Decreased inhibition in the SCRTT was observed after treatment with cyclophosphamide, docetaxel, and topotecan.

CONCLUSIONS

Our data show that, in mice, a single treatment with a cytotoxic agent causes cognitive impairment. Not all cytotoxic agents affected the same cognitive domains, which might be explained by differences in working mechanisms of the various agents.

In vitro-Untersudiungen über Angriffspunkt und Wirkungsunterschiede zum Heparin / In Vitro Studies on the Mode of Action and Differences to Heparin

The effect of a semisynthetic pentosan-polysulfo-ester (SP 54) upon the complement system in vitro has been studied in comparison with the effects of heparin. Both substances inhibit in small concentrations the Cl-esterase. There are differences in the effect of SP 54 and heparin. According to the in vitro results SP 54 seems to have a ten times higher anticomplementary action. At the same time the influence upon coagulation is less. SP 54 appears to be a substance of therapeutic interest.

High-throughput phenotyping of avoidance learning in mice discriminates different genotypes and identifies a novel gene

Recognizing and avoiding aversive situations are central aspects of mammalian cognition. These abilities are essential for health and survival and are expected to have a prominent genetic basis. We modeled these abilities in eight common mouse inbred strains covering ∼75% of the species' natural variation and in gene-trap mice (>2000 mice), using an unsupervised, automated assay with an instrumented home cage (PhenoTyper) containing a shelter with two entrances. Mice visited this shelter for 20-1200 times/24 h and 71% of all mice developed a significant and often strong preference for one entrance. Subsequently, a mild aversive stimulus (shelter illumination) was automatically delivered when mice used their preferred entrance. Different genotypes developed different coping strategies. Firstly, the number of entries via the preferred entrance decreased in DBA/2J, C57BL/6J and 129S1/SvImJ, indicating that these genotypes associated one specific entrance with the aversive stimulus. Secondly, mice started sleeping outside (C57BL/6J, DBA/2J), indicating they associated the shelter, in general, with the aversive stimulus. Some mice showed no evidence for an association between the entrance and the aversive light, but did show markedly shorter shelter residence times in response to illumination, indicating they did perceive illumination as aversive. Finally, using this assay, we screened 43 different mutants, which yielded a novel gene, specc1/cytospinB. This mutant showed profound and specific delay in avoidance learning. Together, these data suggest that different genotypes express distinct learning and/or memory of associations between shelter entrance and aversive stimuli, and that specc1/cytospinB is involved in this aspect of cognition.

PHD3 regulates differentiation, tumour growth and angiogenesis in pancreatic cancer

Purpose:

Tumour hypoxia activates hypoxia-inducible factor-1 (HIF-1) and indluences angiogenesis, cell survival and invasion. Prolyl hydroxylase-3 (PHD3) regulates degradation of HIF-1α. The effects of PHD3 in tumour growth are largely unknown.

Experimental design:

PHD3 expression was analysed in human pancreatic cancer tissues and cancer cell lines by real-time quantitative PCR and immunohistochemistry. PHD3 overexpression was established by stable transfection and downregulation by short interfering RNA technology. VEGF was quantified by enzyme-linked immunosorbent assay. Matrigel invasion assays were performed to examine tumour cell invasion. Apoptosis was measured by annexin-V staining and caspase-3 assays. The effect of PHD3 on tumour growth in vivo was evaluated in an established orthotopic murine model.

Results:

PHD3 was upregulated in well-differentiated human tumours and cell lines, and regulated hypoxic VEGF secretion. PHD3 overexpression mediated tumour cell growth and invasion by induction of apoptosis in a nerve growth factor-dependent manner by the activation of caspase-3 and phosphorylation of focal adhesion kinase HIF-1 independently. In vivo, PHD3 inhibited tumour growth by abrogation of tumour angiogenesis.

Conclusion:

Our results indicate essential functions of PHD3 in tumour growth, apoptosis and angiogenesis and through HIF-1-dependent and HIF-1-independent pathways.

Genetically engineered Lactococcus lactis secreting murine IL-10 modulates the functions of bone marrow-derived dendritic cells in the presence of LPS

Oral delivery of IL-10 by genetically modified Lactococcus lactis (LL-pTmIL10) has been shown to efficiently reduce intestinal inflammation in mice with chronic colitis, but the mechanisms involved have not been elucidated. It has been suggested that IL-10 controls intestinal inflammation by inhibiting microbe-induced activation of dendritic cells. We therefore investigated whether LL-pTmIL10 can modulate the functions of bone marrow-derived dendritic cells (BM-DC) responding to LPS. Incubation of these cells with LL-pTmIL10 or with the control strain LL-pTREX reduced their ability to activate allogeneic T-cell proliferation. However, in contrast to LL-pTREX, LL-pTmIL10 inhibited the LPS-stimulated secretion of MCP-1 by BM-DC and reduced the synergistic up-regulation of IL-12/IL-23p40. In addition, LL-pTmIL10 treatment of LPS-stimulated BM-DC significantly inhibited their capacity to induce strong secretion of IL-17 by CD4+ T cells. Our data suggest that the beneficial effects of LL-pTmIL10 treatment during chronic colitis might involve inhibition of CD4+ Th17 cells and a reduced accumulation of these cells as well as other immune cells at the site of inflammation.

Increased susceptibility of complement factor B/C2 double knockout mice and mannan-binding lectin knockout mice to systemic infection with Candida albicans

Candida albicans is the major cause of systemic fungal infections in immunocompromised patients. We investigated the susceptibility of mice deficient in complement factor B and C2 (Bf/C2-/-), C1q (C1qa-/-), and mannan-binding lectin (MBL)-A (MBL-A) and MBL-C (MBL-A/C-/-) to systemic infection with C. albicans. Animals were infected i.p. with 10(8)C. albicans blastoconidia and monitored for mortality. Bf/C2-/- mice showed high mortality (over 90%) within the study period of 3 weeks. In contrast, mortality in C1qa-/- mice was below 15% whereas that of MBL-A/C-/- mice was 40% (P<0.001). Intravenous infection of mice with 8x10(5) blastoconidia resulted in the same trend with Bf/C2-/- mice being highly susceptible compared to the other strains. Histology of kidney sections of infected Bf/C2-/- mice showed widespread mycelia confirming the high CFU counts from cultured tissue homogenates. In C1qa-/-, MBL-A/C-/- and wild type C57BL/6 mice hyphal growth was limited. However, massive inflammatory infiltration was apparent, which was not seen in Bf/C2-/- mice. The ability of the mouse sera to opsonize C. albicans was determined by quantification of phagocytosis of C. albicans by peritoneal phagocytes. Whilst phagocytosis mediated by Bf/C2-/- mouse serum was low (10.6%), more phagocytosis could be seen in MBL-A/C-/- (19.9%), C1qa-/- mice (23.9%) and wild type mice (29%). Deficiency of classical pathway activation has only a low impact whereas the lectin pathway contributes to the host defence against candidosis. The more pronounced lack of complement activation in Bf/C2-/- mice leads to uncontrolled infection due to an opsonophagocytic defect.

Binding and activation of human and mouse complement by Cryptosporidium parvum (Apicomplexa) and susceptibility of C1q- and MBL-deficient mice to infection

Cryptosporidium parvum is a protozoan parasite (Apicomplexa) that causes gastrointestinal disease in animals and humans. Whereas immunocompetent hosts can limit the infection within 1 or 2 weeks, immunocompromised individuals develop a chronic, life-threatening disease. The importance of the adaptive cellular immune response, with CD4+ T-lymphocytes being the major players, has been clearly demonstrated. Several non-adaptive immune mechanisms have been suggested to contribute to the host defence, such as interferon-gamma (IFN-gamma) from NK cells, certain chemokines, beta-defensins and pro-inflammatory cytokines, but the influence of the complement systems has been less well studied. We analysed the in vitro binding and activation of the human and mouse complement systems and tested the susceptibility to infection in complement-deficient mouse strains. We found that C. parvum can activate both the classical and lectin pathways, leading to the deposition of C3b on the parasite. Using real-time PCR, parasite development could be demonstrated in adult mice lacking mannan-binding lectin (MBL-A/C-/-) but not in mice lacking complement factor C1q (C1qA-/-) or in wild type C57BL/6 mice. The contribution of the complement system and the lectin pathway in particular to the host defence against cryptosporidiosis may become apparent in situations of immunodeficiency such as HIV infections or in early childhood.

Murine trefoil factor 3 does not directly modulate LPS-mediated dendritic cell function

Peptides of the trefoil factor family (TFF) are expressed along the gastro-intestinal tract. They protect mucous epithelia from damage and contribute to mucosal repair, which is essential for preventing inflammation. Moreover, it has been suggested that TFF2 and TFF3, in particular, play a role in regulating immune responses. Depending on their activation status, dendritic cells (DC) can initiate either tolerance or immunity. This study, by comparing LPS-induced maturation of mTFF3-treated DC and non-treated DC, investigated whether murine TFF3 directly regulated DC function. mTFF3-treated DC and non-treated DC did not differ phenotypically or functionally. Both populations expressed, both before and after LPS-stimulation, similar levels of co-stimulatory molecules and cytokines, and were both efficient stimulators of T-cells. Our results suggest that mTFF3 does not govern immune responses on the level of DC function.

Strain specificity and cholinergic modulation of visuospatial attention in three inbred mouse strains

The tremendous increase in the use of mouse inbred strains and mutant mice to study the molecular basis of psychiatric disorders urges for a better understanding of attentional performance in mice. To this aim, we investigated possible strain differences in performance and cholinergic modulation of visuospatial attention in three widely used mouse inbred strains (129S2/SvHsd, C57BL/6JOlaHsd and DBA/2OlaHsd) in the five-choice serial reaction time task. Results indicated that after extended training, performance of 129S2/SvHsd mice was superior to that of C57BL/6JOlaHsd and DBA/2OlaHsd mice in terms of attention, omission errors, inhibitory control and latencies to correct choice. Increasing the attentional load resulted in comparable decrements in attention in all strains and inhibitory control impairments that were most pronounced in DBA/2OlaHsd mice. Further pharmacological evaluation indicated that all strains showed attentional impairments after treatment with the muscarinic and nicotinic antagonists scopolamine and mecamylamine, respectively. 129S2/SvHsd mice were less sensitive, whereas DBA/2OlaHsd mice appeared more sensitive to the detrimental effects of mecamylamine. In addition, subchronic, but not acute, nicotine treatment slightly improved attentional performance in all strains to the same extent. In conclusion, our data indicate strain specificity with particularly good performance of 129S2/SvHsd mice and strong cholinergic involvement in visuospatial attention in mice.

Decreased induction of IL-1β in fibroblast-like synoviocytes: A possible regulatory mechanism maintaining joint homeostasis

The response of fibroblast-like synoviocytes (FLS) to inflammatory stimuli was compared to their, respectively, derived dermal fibroblasts (DF) to determine whether regulatory controls exist within FLS to insure normal joint homeostasis. We further analyzed whether the loss of the normal regulatory controls present within the FLS could predispose to the development of non-rheumatic joint disease (non-RA). Primary fibroblast cell lines were generated from synovial and skin tissue from ten rheumatoid arthritis (RA) and ten non-RA patients. Cell lines were pulse labeled with [(35)S]-methionine and stimulated with TNFalpha or IL-1beta. Protein synthesis of IL-1beta, IL-6 and IL-8 was quantitated following immunoprecipitation. Gene expression was determined by Northern blot analysis. We noted, IL-1beta was minimally detected in FLS under nonstimulated conditions. In response to stimulation with IL-1beta or TNFalpha, production of IL-1beta was found to be 3.5 and 5-fold lower in FLS, respectively, when compared to DF from the same individual. In contrast, the production of IL-6 and IL-8 in FLS upon stimulation was 3-fold and 1.6-fold higher, respectively, than in DF. Furthermore, induced IL-1beta production in FLS, normalized relative to their, respectively, stimulated DF, was 2.5 times higher in non-RA versus RA-derived cells (p=0.032), an effect noted even after several passages of growth. Our data suggest that inductive expression of IL-1beta in FLS is under specific inhibitory control. Increased production of IL-1beta in FLS of susceptible individuals may lead to a higher risk of developing severe joint damage even in the absence of systemic inflammation.

Involvement of complement pathways in patients with bacterial septicemia

The complement system is a major humoral portion of the innate immune system, playing a significant role in host defence against microorganisms. The biological importance of this system is underlined by the fact that at least three different pathways for its activation exist, the classical, the MBL and the alternative pathway. To elucidate the involvement of the classical and/or the MBL pathway during bacterial septicemia, 32 patients with gram-positive and 30 patients with gram-negative bacterial infections were investigated. In patients with gram-positive bacteria, a significant consumption of C1q (p=0.005) but not of mannose-binding lectin (MBL) (p=0.2) was found during the acute phase of infection. In contrast, in patients with gram-negative bacterial infections, a significant reduction of MBL (p=0.002) and only a moderate, less significant reduction of C1q (p=0.03) were observed. As a model for the binding of MBL to gram-negative bacteria, Salmonella strains with defined mutations in their lipopolysaccharide (LPS) structure were used. The comparison of the binding of MBL to these Salmonella strains with that of the corresponding isolated LPS forms bound to microtiter plates revealed a similar binding pattern, supporting the interpretation that LPS on the surface of gram-negative bacteria is the major acceptor molecule for MBL on these bacteria, which according to our results obviously also takes place during gram-negative bacterial septicaemia. Furthermore, we were able to demonstrate that MBL bound to LPS was able to initiate activation of the complement cascade as measured by the occurrence of the cleavage product C4c.

Human macrophages simultaneously express membrane-C1q and Fc-receptors for IgG

Membrane C1q (mC1q) of macrophages (MPhi) is a precursor of the IgG-binding serum protein C1q. Thus, mC1q potentially provides one of several Fcgamma binding sites of mature MPhi and we analyzed whether simultaneous expression occurs of established receptors for IgG, FcgammaRI, II, and III, and mC1q during in vitro differentiation of MPhi. Using flow cytometry, immunoprecipitation combined with Western blotting and Northern blot analysis mC1q was hardly detected in freshly isolated blood monocytes, but increasingly in developing monocyte-derived MPhi. Laser scanning fluorescence microscopy confirmed the membrane localization of mC1q. Two-color-staining flow cytometry experiments indicated that mC1q and all three types of FcgammaRs are simultaneously expressed on mature monocyte-derived MPhi. A high correlation was found for the expression of mC1q and FcgammaRs, in particular FcgammaRII, but not mC1q and CD14, another marker of monocytes/MPhi.

Common silent mutations in all types of hereditary complement C1q deficiencies

Hereditary complete deficiency of complement component C1q is a rare genetic disorder that is associated with severe recurrent infections and a high prevalence of lupus-erythematosus-like symptoms. In the past, several single nucleotide polymorphisms have been identified in all three genes coding for the C1q A, B, and C chains. These point mutations which either lead to termination codons, frameshift, or amino acid exchanges were thought to be responsible for these defects as no other nonsense or missense mutations were found. As a result of the aberrations, either a nonfunctional C1q antigen is present or no C1q protein is detectable in the patients' sera. Screening 46 individuals from seven families with different forms of C1q deficiencies identified a homologous silent mutation at position Gly70 (GGG > GGA) of the C1q A gene of all 11 C1q-deficient patients. A high number of family members that were heterozygous for the coding mutations carried the silent mutation in the homozygous (18%) or heterozygous (36%) state. In addition to the Gly70 mutation in the A gene, another homozygous silent mutation (C gene at position Pro14, CCT >CCC) was detected in all C1q-deficient patients.

Inflammation in areas of remote changes following focal brain lesion

Focal brain lesions can lead to metabolic and structural changes in areas distant from but connected to the lesion site. After focal ischemic or excitotoxic lesions of the cortex and/or striatum, secondary changes have been observed in the thalamus, substantia nigra pars reticulata, hippocampus and spinal cord. In all these regions, inflammatory changes characterized by activation of microglia and astrocytes appear. In the thalamus, substantia nigra pars reticulata and hippocampus, an expression of proinflammatory cytokine like tumor necrosis factor-alpha and interleukin-1beta is induced. However, time course of expression and cellular localisation differ between these regions. Neuronal damage has consistently been observed in the thalamus, substantia nigra and spinal cord. It can be present in the hippocampus depending on the procedure of induction of focal cerebral ischemia. This secondary neuronal damage has been linked to antero- and retrograde degeneration. Anterograde degeneration is associated with somewhat later expression of cytokines, which is localised in neurons. In case of retrograde degeneration, the expression of cytokines is earlier and is localised in astrocytes. Pharmacological intervention aiming at reducing expression of tumor necrosis factor-alpha leads to reduction of secondary neuronal damage. These first results suggest that the inflammatory changes in remote areas might be involved in the pathogenesis of secondary neuronal damage.

Activation of the lectin pathway in murine lupus nephritis

In systemic lupus erythematosus (SLE), hypocomplementaemia and complement deposition have been described both in man and in experimental models. A major involvement of the classical pathway of complement activation has been demonstrated in this disease, however relatively little is known about the involvement of the lectin pathway. Therefore in the present study we have analyzed the activity of all three pathways of complement activation in murine models of SLE. In the mouse, MBL is expressed in two forms, namely MBL-A and MBL-C. In the present study young and old MRL-lpr and control MRL+/+ mice were compared for the levels of complement activity with specific attention for the lectin pathway. It was found that upon aging of both MRL-lpr and MRL+/+ mice, a marked decrease in the activity of the classical pathway (CP) occurs. Levels of alternative pathway (AP) and lectin pathway (LP) activity remain unchanged. Key-molecules of these pathways, C1q, C3, MBL-A and MBL-C were analyzed and were all found to be decreased in aged mice of both strains. The levels of MBL-A and MBL-C showed a high degree of correlation and decreased equally. In aged MRL-lpr mice in which autoimmunity is most pronounced, we observed high autoantibody titers and strong deposition of glomerular immune complexes in association with deposition of C1q, C3, MBL-A and MBL-C. In conclusion, these data suggest that in addition to the classical pathway and the alternative pathway also the lectin pathway of complement activation is involved in murine lupus nephritis.

The critical concentration of C1-esterase inhibitor (C1-INH) in human serum preventing auto-activation of the first component of complement (C1)

C1-esterase inhibitor (C1-INH) was depleted from normal human serum (NHS) at 4 degrees C by affinity chromatography with a monoclonal anti-C1-INH antibody (mAb 13 E1) coupled to CNBr-activated Sepharose 4B. The C1-INH-depleted serum (C1-INH-depl-HS) had normal levels of C1, C4, and CH 50 and C1-INH concentration was less than 10% of normal (15 microg/ml in C1-INH-depl-HS compared to 230 microg/ml in NHS). C1-auto-activation in C1-INH-depl-HS was followed by measuring C4-consumption in a haemolytic assay and by detection of activated C1s in a C1s-ELISA. After a lag phase of 10-20 min, C1-auto-activation in C1-INH depl-HS occurred and reached its maximum after 40 min at 37 degrees C. In contrast, neutralization of C1-INH activity in NHS by addition of monoclonal antibodies directed against its C1s-binding site, resulted in an immediate, spontaneous C1-activation without a lag-phase and reached its maximum already after 20 min (mAb 140) and 25 min (mAb 88G2). Addition of highly purified C1-INH or NHS as source of C1-INH to C1-INH-depleted serum to a final concentration of 55 microg/ml (22% of normal C1-INH concentration in HS) was sufficient to control spontaneous C1-activation.

Linking C5 Deficiency to an Exonic Splicing Enhancer Mutation

As an important component of the innate immune system, complement provides the initial response to prevent infections by pathogenic microorganisms. Patients with dysfunction of C5 display a propensity for severe recurrent infections. In this study, we present a patient with C5 deficiency demonstrated by immunochemical and functional analyses. Direct sequencing of all C5 exons displayed no mutation of obvious functional significance, except for an A to G transition in exon 10 predicting an exchange from lysine to arginine. This sequence alteration was present in only one allele of family members with a reduced serum C5 concentration and in both alleles of the patient with almost complete C5 deficiency, suggesting that this alteration may be producing the phenotype. Recent findings indicate that distinct nucleotide sequences, termed exonic splicing enhancers (ESEs), influence the splicing process. cDNA from all family members harboring the mutated allele showed skipping of exon 10, which resulted in a premature STOP codon, explaining the lack of C5 in the propositus. Sequence analysis of the mutated region revealed the substitution to be located within an ESE, as predicted by the RESCUE-ESE program. The altered ESE sequence is located close to the 5' splicing site and also lowers the predicted strength of the splice site itself. This apparently inconsequential sequence alteration represents a noncanonical splicing mutation altering an ESE. Our finding sheds a new light on the role of putative silent/conservative mutations in disease-associated genes.

Functional analysis of the classical, alternative, and MBL pathways of the complement system: standardization and validation of a simple ELISA

Primary defence against invading microorganisms depends on a functional innate immune system and the complement system plays a major role in such immunity. Deficiencies in one of the components of the complement system can cause severe and recurrent infections, systemic diseases, such as systemic lupus erythematosus (SLE) and renal disease. Screening for complement deficiencies in the classical or alternative complement pathways has mainly been performed by haemolytic assays. Here, we describe a simple ELISA-based format for the evaluation of three pathways of complement activation. The assays are based on specific coatings for each pathway in combination with specific buffer systems. We have standardized these assays and defined cut off values to detect complement deficiencies at the different levels of the complement system. The results demonstrate the value of these ELISA-based procedures for the functional assessment of complement deficiencies in clinical practice. The assay is now available commercially in kit form.

Restoration of C1q levels by bone marrow transplantation attenuates autoimmune disease associated with C1q deficiency in mice

C1q deficiency in both humans and mice is strongly associated with autoimmunity. We have previously shown that bone marrow transplantation (BMT) restored C1q levels in C1q-deficient (C1qa(-/-)) mice. Here, we studied the effect of BMT on autoimmunity in C1qa(-/-) mice. Following irradiation, young C1qa(-/-) or wild-type MRL/Mp mice received bone marrow cells (BMC) from strain-matched wild-type or C1qa(-/-) animals. C1q levels increased rapidly when C1qa(-/-) mice received BMC from wild-type mice. Conversely, they decreased slowly in wild-type mice transplanted with C1qa(-/-) BMC. C1qa(-/-) animals transplanted with C1qa(-/-) BMC demonstrated accelerated disease when compared with wild-type mice given wild-type BMC. In contrast, a significant delay in the development of autoantibodies and glomerulonephritis was observed in C1qa(-/-) mice reconstituted with wild-type BMC, and the impaired clearance of apoptotic cells, previously described in C1qa(-/-) mice, was rectified. Moreover, the autoimmune disease was accelerated in wild-type mice given C1qa(-/-) BMC compared to animals transplanted with wild-type cells. These results provide supporting evidence that BMT may be a therapeutic option in the treatment of autoimmunity associated with human C1q deficiency.

Association between inflammation and nigral neuronal damage following striatal excitotoxic lesion

We examined the expression of TNF-alpha within the substantia nigra pars reticulata (SNR) following intrastriatal injection of quinolinic acid (QA) and studied the effect of rolipram, a TNF-alpha-inhibitor, on the secondary neuronal damage. QA (240 nmol in 1 microl) was injected stereotactically into the striatum of male Wistar rats. After survival of 1, 3 or 10 days, the animals were sacrificed and immunohistochemical staining with an antibody against TNF-alpha was performed. From day 1 to day 10 after striatal QA injection TNF-alpha positive cells were observed within ipsilateral substantia nigra which were neither present on the contralateral side nor in sham-operated controls. Double labeling with antibodies against TNF-alpha and NeuN, keratan sulfate proteoglycan or GFAP displayed a good overlap between TNF-alpha and NeuN, which suggests that TNF-alpha positive cells are neurons. For the pharmacological approach, three groups of QA rats were treated intraperitoneally with either solvent (n=5), the NMDA receptor antagonist MK 801 (4 mg/kg, n=6) or the TNF-alpha inhibitor rolipram (0.3 mg/kg, n=6), which was started 24 h after QA-injection and continued with daily applications for 14 days. The amount of striatal damage did not differ between the three groups. The number of intact neurons within the ipsilateral substantia nigra of the solvent treated group was reduced by approximately 30% compared to the contralateral side. Both MK 801 and rolipram ameliorated this secondary damage and reduced the number of TNF-alpha positive cells. The observed association between expression of TNF-alpha and secondary neuronal damage within the substantia nigra induced by intrastriatal QA application might hint towards an involvement of this cytokine in transneuronal degeneration.

Differential expression of the murine mannose-binding lectins A and C in lymphoid and nonlymphoid organs and tissues

Mannose-binding lectin (MBL), a member of the collectin family, binds to carbohydrate structures on the surfaces of micro-organisms and may serve as a recognition molecule of the lectin pathway of complement activation. In rodents two forms, MBL-A and MBL-C, were described and shown to be products of two related, but uncoupled, genes. The liver is the main source of MBL biosynthesis. For rat MBL-A, expression has also been described in the kidney. Here we report that the two forms of murine MBL are differentially expressed in a number of nonhepatic tissues. Real-time RT-PCR revealed that the liver is the major site of expression for both MBL genes. Lower copy numbers were found in kidney, brain, spleen, and muscle. In testis, only the MBL-A gene is expressed, whereas MBL-C is exclusively expressed in small intestine. Using in situ hybridization and immunohistochemistry, we demonstrate that both MBLs are synthesized by hepatocytes and show MBL expression in cells of the monocyte/macrophage lineage. In the kidney MBL-A, but not MBL-C, was found to be synthesized. Vice versa, only MBL-C biosynthesis was detected in endothelial cells of the small intestine. The latter finding may support the view that MBL-C, as part of the innate immune system, may be a counterpart of secretory IgA of the acquired immune system in preventing, for example, microbial invasion and colonization. Our findings demonstrate that MBL-A and MBL-C are differentially expressed, implying distinct biological roles for both recognition molecules of the murine lectin pathway of complement.