UVA-induced metabolic changes in non-malignant skin cells and the potential role of pyruvate as antioxidant

The exposure to UVA (320-400 nm) irradiation is a major threat to human skin concerning photoaging and carcinogenesis. It has been shown that UVA irradiation can induce reactive oxygen species (ROS) and DNA mutations, such as 8-hydroxydeoxyguanosine. Furthermore, UVA induces the expression of photoaging-associated matrix metalloproteases (MMPs), especially of matrix metalloprotease 1 (MMP 1) and matrix metalloprotease 3 (MMP 3). In addition to this, it was recently shown that UVA-induced ROS also increase glucose metabolism of melanoma cells, however, the influence of UVA on the glucose metabolism of non-malignant cells of the human skin has, so far, not been investigated in detail. Here, we investigated the UVA-induced changes in glucose metabolism and the functional relevance of these changes in primary fibroblasts-normal non-malignant cells of the skin. These cells showed an UVA-induced enhanced glucose consumption and lactate production and changes in pyruvate production. As it has been proposed that pyruvate could have antioxidant properties we tested the functional relevance of pyruvate as protective agent against UVA-induced ROS. Our initial experiments support earlier publications, demonstrating that pyruvate treated with H2O2 is non-enzymatically transformed to acetate. Furthermore, we show that this decarboxylation of pyruvate to acetate also occurs upon UVA irradiation. In addition to this, we could show that in fibroblasts pyruvate has antioxidant properties as enhanced levels of pyruvate protect cells from UVA-induced ROS and partially from a DNA mutation by the modified base 8-hydroxydeoxyguanosine. Furthermore, we describe for the first time, that the interaction of UVA with pyruvate is relevant for the regulation of photoaging-associated MMP 1 and MMP 3 expression.

A microbial eukaryote with a unique combination of purple bacteria and green algae as endosymbionts

Oxygenic photosynthesizers (cyanobacteria and eukaryotic algae) have repeatedly become endosymbionts throughout evolution. In contrast, anoxygenic photosynthesizers (e.g., purple bacteria) are exceedingly rare as intracellular symbionts. Here, we report on the morphology, ultrastructure, lifestyle, and metagenome of the only "purple-green" eukaryote known. The ciliate Pseudoblepharisma tenue harbors green algae and hundreds of genetically reduced purple bacteria. The latter represent a new candidate species of the Chromatiaceae that lost known genes for sulfur dissimilation. The tripartite consortium is physiologically complex because of the versatile energy metabolism of each partner but appears to be ecologically specialized as it prefers hypoxic sediments. The emergent niche of this complex symbiosis is predicted to be a partial overlap of each partners' niches and may be largely defined by anoxygenic photosynthesis and possibly phagotrophy. This purple-green ciliate thus represents an extraordinary example of how symbiosis merges disparate physiologies and allows emergent consortia to create novel ecological niches.

Randomised controlled trial of early detection and cognitive therapy for preventing transition to psychosis in high-risk individuals

Background

There is interest in the possibility of indicated prevention of psychosis. There is a strong case for using psychological approaches to prevent transition to psychosis in high-risk patients.

Aims

To identify individuals at high risk of transition to psychosis, and psychological characteristics relevant to the development of psychosis in this group.

Method

The design of a randomised controlled trial of cognitive therapy for the prevention of psychosis in people at high risk (meeting operational criteria of brief or attenuated psychotic symptoms, or first-degree family history with functional decline) is outlined. The first patients recruited are compared with non-patient samples on cognitive and personality factors; an interim analysis of transition rate is reported.

Results

Cases (n=31) were recruited mainly from primary care. Of the 23 high-risk patients monitored for 6–12 months, 5 (22%) made the transition to psychosis. The high-risk group scored significantly higher than non-patients on measures of schizotypy, metacognitive beliefs and dysfunctional self-schemas (sociotropy).

Conclusions

The findings validate the methods of identifying individuals at high risk of experiencing a psychotic episode. Compared with non-patient controls, the cases showed dysfunctional metacognitive beliefs and self-schemas.

Co-delivery of PLGA encapsulated invariant NKT cell agonist with antigenic protein induce strong T cell-mediated antitumor immune responses

Antitumor immunity can be enhanced by the coordinated release and delivery of antigens and immune-stimulating agents to antigen-presenting cells via biodegradable vaccine carriers. So far, encapsulation of TLR ligands and tumor-associated antigens augmented cytotoxic T cell (CTLs) responses. Here, we compared the efficacy of the invariant NKT (iNKT) cell agonist α-galactosylceramide (α-GalCer) and TLR ligands (R848 and poly I:C) as an adjuvant for the full length ovalbumin (OVA) in PLGA nanoparticles. We observed that OVA+α-GalCer nanoparticles (NP) are superior over OVA+TLR-L NP in generating and stimulating antigen-specific cytotoxic T lymphocytes without the need for CD4+ T cell help. Not only a 4-fold higher induction of antigen-specific T cells was observed, but also a more profound IFN-γ secretion was obtained by the addition α-GalCer. Surprisingly, we observed that mixtures of OVA containing NP with α-GalCer were ineffective, demonstrating that co-encapsulation of both α-GalCer and antigen within the same nanoparticle is essential for the observed T cell responses. Moreover, a single immunization with OVA+α-GalCer NP provided substantial protection from tumor formation and even delayed the growth of already established tumors, which coincided with a prominent and enhanced antigen-specific CD8+ T cell infiltration. The provided evidence on the advantage of antigen and α-GalCer coencapsulation should be considered in the design of future nanoparticle vaccines for therapeutic purposes.

Enhancing neurosteroid synthesis--relationship to the pharmacology of translocator protein (18 kDa) (TSPO) ligands and benzodiazepines

INTRODUCTION

The treatment of anxiety disorders is still a challenge; novel pharmacological approaches that combine rapid anxiolytic efficacy with fewer side effects are needed. A promising target for such compounds is the mitochondrial translocator protein (18 kDa) (TSPO). TSPO plays an important role for the synthesis of neurosteroids, known to modulate GABAA receptors, thereby exerting anxiolytic effects.

METHODS

We investigated the pharmacological profile of 2 well established TSPO ligands (XBD173 and etifoxine) compared to the benzodiazepine diazepam with regard to TSPO binding affinity, TSPO expression and neurosteroidogenesis.

RESULTS

In BV-2 microglia and C6 glioma cells all compounds significantly enhanced TSPO protein expression. Radioligand binding assays revealed the highest binding affinity to TSPO for XBD173, followed by diazepam and etifoxine. Pregnenolone synthesis was most potently enhanced by etifoxine.

DISCUSSION

Etifoxine turned out to be the most potent enhancer of neurosteroidogenesis, although its binding affinity to TSPO was lowest. These results indicate that the efficacy of TSPO ligands to stimulate neurosteroid synthesis, thereby leading to anxiolytic effects cannot be concluded from their binding affinity to TSPO.

Targeted delivery of a sialic acid-blocking glycomimetic to cancer cells inhibits metastatic spread

Sialic acid sugars are overexpressed by cancer cells and contribute to the metastatic cascade at multiple levels. Therapeutic interference of sialic acids, however, has been difficult to pursue because of the absence of dedicated tools. Here we show that a rationally designed sialic acid-blocking glycomimetic (P-3F(ax)-Neu5Ac) successfully prevents cancer metastasis. Formulation of P-3F(ax)--Neu5Ac into poly(lactic-co-glycolic acid nanoparticles coated with antityrosinase-related protein-1 antibodies allowed targeted delivery of P-3F(ax)--Neu5Ac into melanoma cells, slow release, and long-term sialic acid blockade. Most importantly, intravenous injections of melanoma-targeting P-3F(ax)--Neu5Ac nanoparticles prevented metastasis formation in a murine lung metastasis model. These findings stress the importance of sialoglycans in cancer metastasis and advocate that sialic acid blockade using rationally designed glycomimetics targeted to cancer cells can effectively prevent cancer metastases. This targeting strategy to interfere with sialic acid-dependent processes is broadly applicable not only for different types of cancer but also in infection and inflammation.

Pyrosequencing: powerful and quantitative sequencing technology

Pyrosequencing is a sequencing-by-synthesis method for DNA analysis that has emerged as a platform not only for de novo sequencing applications, but also for quantitative analysis of genomic methylation, single-nucleotide polymorphisms, and allele quantification. In this unit, we describe a complete workflow from sample to result that is suitable for each of these applications. As cytosine conversion is a key element of successful methylation analysis using pyrosequencing, a support protocol for bisulfite treatment is also included.

Dendritic cell-based nanovaccines for cancer immunotherapy

Cancer immunotherapy critically relies on the efficient presentation of tumor antigens to T-cells to elicit a potent anti-tumor immune response aimed at life-long protection against cancer recurrence. Recent advances in the nanovaccine field have now resulted in formulations that trigger strong anti-tumor responses. Nanovaccines are assemblies that are able to present tumor antigens and appropriate immune-stimulatory signals either directly to T-cells or indirectly via antigen-presenting dendritic cells. This review focuses on important aspects of nanovaccine design for dendritic cells, including the synergistic and cytosolic delivery of immunogenic compounds, as well as their passive and active targeting to dendritic cells. In addition, nanoparticles for direct T-cell activation are discussed, addressing features necessary to effectively mimic dendritic cell/T-cell interactions.

Integrated expression profiling of multiple RNA species by real-time PCR

MicroRNAs (miRNAs) are endogenous, non-coding RNAs comprising approximately 21-23 nucleotides that regulate gene expression by binding to and targeting messenger RNA (mRNA) for translational repression or degradation. miRNAs have been shown to regulate cellular processes including proliferation, differentiation, and development and to play an important role in immune system function. The expression of miRNAs is misregulated in numerous diseases, including cancers of immunological origin. To better understand the role of miRNA in T-cell activation, we used a real-time PCR-based system to analyze changes in miRNA expression following activation of Jurkat T-cells with the inducing agents Phorbol Myristyl Acetate (PMA) and Ionomycin (CI) and detected several miRNAs that showed differential regulation following treatment. Using this system, miRNAs and their mRNA targets, along with other non-coding RNAs, can be simultaneously detected and quantified using SYBR® Green real time-PCR, enabling comprehensive, genome-wide expression profiles of multiple RNA species.

Morphological and molecular characterization of Paramecium (Viridoparamecium nov. subgen.) chlorelligerum Kahl (Ciliophora)

We redescribe Paramecium chlorelligerum, a forgotten species, which Kahl (Tierwelt Dtl., 1935, 30:651) briefly but precisely described in the addendum to his ciliate monographs as a Paramecium with symbiotic green algae. The redescription is based on classical morphological methods and the analysis of the small subunit (SSU) rDNA. Morphologically, P. chlorelligerum differs from P. (C.) bursaria, the second green species in the genus, by having a special swimming shape, the length of the caudal cilia, the size of the micronucleus, the size of the symbiotic algae, the contractile vacuoles (with collecting vesicles vs. collecting canals), and the number of excretory pores/contractile vacuole (1 vs. 2-3). The molecular investigations show that P. chlorelligerum forms a distinct branch distant from the P. (Chloroparamecium) bursaria clade. Thus, we classify P. chlorelligerum in a new subgenus: Paramecium (Viridoparamecium) chlorelligerum. The symbiotic alga belongs to the little-known genus Meyerella, as yet recorded only from the plankton of a North American lake.

Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity

Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC) by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is paramount. However, co-administration of unlinked adjuvant cannot ensure that all cells targeted by the antibody conjugates are appropriately activated. Furthermore, antigen-presenting cells (APC) that do not present the desired antigen are equally strongly activated and could prime undesired responses against self-antigens. We, therefore, were interested in exploring targeted co-delivery of antigen and adjuvant in cis in form of antibody-antigen-adjuvant conjugates for the induction of anti-tumour immunity. In this study, we report on the assembly and characterization of conjugates consisting of DEC205-specific antibody, the model antigen ovalbumin (OVA) and CpG oligodeoxynucleotides (ODN). We show that such conjugates are more potent at inducing cytotoxic T lymphocyte (CTL) responses than control conjugates mixed with soluble CpG. However, our study also reveals that the nucleic acid moiety of such antibody-antigen-adjuvant conjugates alters their binding and uptake and allows delivery of the antigen and the adjuvant to cells partially independently of DEC205. Nevertheless, antibody-antigen-adjuvant conjugates are superior to antibody-free antigen-adjuvant conjugates in priming CTL responses and efficiently induce anti-tumour immunity in the murine B16 pseudo-metastasis model. A better understanding of the role of the antibody moiety is required to inform future conjugate vaccination strategies for efficient induction of anti-tumour responses.

[Position Paper of the Youth Forum DGOU 2010 - part 2]

The aim of the "Youth Forum of the DGOU" during the Convention 2010 in Heidelberg was to place a statement concerning the professional politics in the field of Orthopaedic and Trauma Surgery. The Bologna Process realizes a standardization of the academic training within the European Union. For medicine this concept would raise the opportunity to opt out after three years with a bachelor degree applying for alternative occupations within the health care system. However, these alternative occupations are rarely defined and, in addition, the current structure of medical school in Germany provides the highest possible education for doctors in a direct and very well established way. Thus, reforming medical school in Germany into a Bachelor-master's system is an ambivalent approach, which considers a thorough reappraisal. There is currently no necessity for an speciality training in emergency medicine. The rapid and qualified treatment by the specific subspecialty provides a high standard of care for the patient. The high frequency exposure of the trauma and orthopaedic resident with emergency cases is an essential part of the current professional training.The "Junge Forum der DGOU" continues to understand the speciality training "Facharzt für Orthopädie und Unfallchirurgie" as the basic module of the profession. After that it should be possible to continuing subspecialty training and obtaining "spezielle Unfallchirurgie" bzw "spezielle orthopädische Chirurgie". After that further subspecialty training should be encouraged.

[Position Paper of the Youth Forum DGOU 2010 - part 1]

The aim of the "Youth Forum of the DGOU" during the Convention 2010 in Heidelberg was to place a statement concerning the professional politics in the field of Orthopaedic and Trauma Surgery. The emigration of young German physicians, the occupational image of the Physician Assistant and the quality of the German residency programs in Orthopaedic and Trauma Surgery we discussed as main topics. The main reason for young German physicians to go abroad is, besides better work conditions and less bureaucracy, the better structured education during residency. Therefore the "Youth Forum" generally supports the concept of the "physician assistant" as "a relief from non-physician duties rather than discussing the delegation of true physician duties". The "Youth Forum" is looking forward to collaborating on the improvement of the ongoing education of residents. In this regard, Orthopaedic and Trauma Surgery needs to become more attractive for young academics. We also support a uniform and nationwide curriculum, which guarantees a structured education to improve the theoretic, practical and academic skills of the future specialist in orthopaedic and trauma surgery. Additional surveys and interviews among the current generation of residents are needed to further specify the potential goals of such a curriculum. We would like to discuss the future of our speciality with our colleagues. Therefore different communication platforms including our website http://www.jf-dgou.de have been created.

Interleukin-10 promotes NK cell killing of autologous macrophages by stimulating expression of NKG2D ligands

Under inflammatory conditions, the pleiotropic cytokine interleukin-10 (IL-10) is released in many tissues. It mediates anti-inflammatory effects in particular by inhibiting the release of T helper type 1 (Th1) cytokines. In contrast, we show here that NK cell cytotoxicity against autologous macrophages is elevated if both cell types are cultured with IL-10. The expression of most activatory NK receptors is increased after culture in the presence of IL-10. On the other hand, macrophages cultured in the presence of IL-10 show elevated expression of the NKG2D ligands major histocompatibility complex (MHC) class 1-like molecules (MIC) - A and - B, as well as UL-16 binding proteins (ULBP) - ULBP-1, ULBP-2 and ULBP-3. By masking the interaction of NK cells with macrophages through interruption of the NKG2D receptor with its ligands, we could reverse the IL-10-induced lysis of macrophages. Our data therefore reveal that IL-10 may exert a novel immunomodulatory role by stimulating NKG2D ligand expression on macrophages, thereby rendering them susceptible to NK cell elimination. This suggests that NK cells would delete macrophages and potentially other immature antigen-presenting cells (APC) or their precursors under inflammatory conditions as a feedback mechanism to shut off uncontrolled immune responses.

CD rats as an animal model in the experimental study of laparoscopic hernia repair

PURPOSE

The aim of this study was to evaluate the technical feasibility and efficacy of a sutureless laparoscopic hernia repair in a small animal model. The objective was to occlude the processus vaginalis with biocompatible fleece and/or fibrin glue as an alternative to suturing.

METHODS

Sixty-three male CD rats were randomly assigned to one of three groups. In group A (n=21), the internal inguinal ring was filled with 0.5 ml fibrin glue. The second group (B, n=21) also received fibrin glue, and a biocompatible fleece was placed on top. The third group consisted of control animals (C, n=21). Eleven rats in each group underwent laparoscopic surgery. The remaining rats were operated using an open technique, and the paraductal lipomas were resected in addition to inguinal ring closure.

RESULTS

Complete closure of the internal hernia ring was not achieved in any of the rats, neither in the laparoscopic group nor in the open group or the control group. The paraductal lipoma grew back to its normal size, although resection of the lipoma was performed during the first procedure.

CONCLUSION

The physiology of paraductal lipomas in this animal appears to make it an inadequate model for the study of laparoscopic inguinal hernia repair.

Expression of CD68 in non-myeloid cell types

CD68, the human homologue of macrosialin, is commonly regarded as a selective marker for human monocytes and macrophages. Its expression is thought to be regulated by a macrophage-specific promoter. However, several immunohistochemical studies have indicated that CD68 antibodies also react with other haematopoietic and non-haematopoietic cell types. We investigated the expression of CD68 in various primary cells and carcinoma cell lines using immunohistochemistry, flow cytometry, Western blot analysis and qRT-PCR. Weak but significant immunoreactivity was detected in lymphocytes and several tumour cell lines whereas staining of primary fibroblasts and endothelial cells was comparable to macrophages. The intensity of CD68 staining in individual cell types depended on the antibody clone and the fixation technique. Anti-CD68 mAb KP1 should be used with great caution for frozen tissue sections due to its reactivity with a wide variety of cell types. Also, care should be taken when distinguishing macrophages from fibroblasts/stromal cells in paraffin sections after formalin fixation since both cell types are stained highly positive for CD68. In accordance, mRNA expression of CD68 was not only detected in macrophages and monocytes but also in fibroblasts as well as endothelial cells and tumour cells, although with a varying intensity. Cloning of full length 5'-sequences and determination of transcription start sites shows that macrophages and fibroblasts initiate transcription within the known promoter region; however, from different start sites, indicating alternative promoter architecture in myeloid versus non-myeloid cells. We suggest that CD68 is not a selective macrophage marker but rather a lysosomal protein that is enriched in macrophages.

Caldendrin-Jacob: a protein liaison that couples NMDA receptor signalling to the nucleus

NMDA (N-methyl-D-aspartate) receptors and calcium can exert multiple and very divergent effects within neuronal cells, thereby impacting opposing occurrences such as synaptic plasticity and neuronal degeneration. The neuronal Ca2+ sensor Caldendrin is a postsynaptic density component with high similarity to calmodulin. Jacob, a recently identified Caldendrin binding partner, is a novel protein abundantly expressed in limbic brain and cerebral cortex. Strictly depending upon activation of NMDA-type glutamate receptors, Jacob is recruited to neuronal nuclei, resulting in a rapid stripping of synaptic contacts and in a drastically altered morphology of the dendritic tree. Jacob's nuclear trafficking from distal dendrites crucially requires the classical Importin pathway. Caldendrin binds to Jacob's nuclear localization signal in a Ca2+-dependent manner, thereby controlling Jacob's extranuclear localization by competing with the binding of Importin-alpha to Jacob's nuclear localization signal. This competition requires sustained synapto-dendritic Ca2+ levels, which presumably cannot be achieved by activation of extrasynaptic NMDA receptors, but are confined to Ca2+ microdomains such as postsynaptic spines. Extrasynaptic NMDA receptors, as opposed to their synaptic counterparts, trigger the cAMP response element-binding protein (CREB) shut-off pathway, and cell death. We found that nuclear knockdown of Jacob prevents CREB shut-off after extrasynaptic NMDA receptor activation, whereas its nuclear overexpression induces CREB shut-off without NMDA receptor stimulation. Importantly, nuclear knockdown of Jacob attenuates NMDA-induced loss of synaptic contacts, and neuronal degeneration. This defines a novel mechanism of synapse-to-nucleus communication via a synaptic Ca2+-sensor protein, which links the activity of NMDA receptors to nuclear signalling events involved in modelling synapto-dendritic input and NMDA receptor-induced cellular degeneration.

Differentiation of human tumour-associated dendritic cells into endothelial-like cells: an alternative pathway of tumour angiogenesis

Until recently, the only accepted mechanism of tumour vascularization was the sprouting of endothelial cells (EC) from pre-existing vessels, while recent studies suggest the contribution of stem cell-derived endothelial progenitors as well as cells from the myeloid lineage. Here, we show a new way of endothelial differentiation that involves the specific modulation of monocytes by the tumour environment. The tumour milieu is characterized by the presence of cytokines and lactate which induce the differentiation of tumour-invading monocytes into tumour-associated dendritic cells (DC). Additional incubation of tumour-associated DC with pro-angiogenic factors, such as vascular endothelial growth factor and oncostatin M, led to transdifferentiation into endothelial-like cells. The cells showed strong expression of von Willebrand factor and VE-Cadherin, both classical EC markers, while leukocytic markers were reduced. In addition, they were able to form network-like structures on matrigel, which could be blocked by the DNA-based drug Defibrotide. This finding may be of great therapeutic relevance for tumour therapy.

Decay of 1+ states as a new probe of the structure of 0+ shape isomers

The nuclides 98Mo and 100Mo have been studied in photon-scattering experiments by using bremsstrahlung produced from electron beams with kinetic energies from 3.2 to 3.8 MeV. Six electromagnetic dipole transitions in 98Mo and 19 in 100Mo were observed for the first time in the energy range from 2 to 4 MeV. A specific feature in the two nuclides is the de-excitation of one state with spin J = 1 to the 0+ ground state as well as to the first excited 0+ state, which cannot be explained in standard models. We present a model that allows us to deduce the mixing coefficients for the two 0+ shape-isomeric states from the experimental ratio of the transition strengths from the J = 1 state to the 0+ ground state and to the 0+ excited state.

The Apertospathulidae, a New Family of Haptorid Ciliates (Protozoa, Ciliophora)

We studied the morphology of three rare haptorid ciliates, using live observation and silver impregnation: Apertospathula verruculifera n. sp., Longispatha elegans n. gen., n. sp., and Rhinothrix porculus (Penard, 1922) n. gen., n. comb. Simple ethanol fixation (50-70%, v/v) is recommended to reveal the ciliary pattern of "difficult" ciliates, such as R. porculus, by protargol impregnation. The three genera investigated have a distinct feature in common, viz., a lasso-shaped oral bulge and circumoral kinety, where the right half is slightly to distinctly longer than the left and the circumoral kinety is open ventrally. Thus, they are united in a new spathidiid family, the Apertospathulidae n. fam., which probably evolved from a Bryophyllum-like ancestor by partial reduction of the oral bulge and circumoral kinety. Apertospathula verruculifera has a wart-like process, the palpus dorsalis, at the anterior end of the dorsal brush. The right branch of the circumoral kinety is only slightly longer than the left one. Longispatha elegans has a straight oral bulge and circumoral kinety, the right branch of which extends to the posterior end of the body while the left branch ends in the anterior third of the body. Rhinothrix porculus, a curious ciliate with a snout-like dorsal elongation of the oral bulge, the palpus oralis, has a highly characteristic ciliary pattern: the oral pattern is as in Longispatha, but the bulge and circumoral kinety extend spirally to the posterior end of the body while the somatic kineties course meridionally. This is achieved by inserting some shortened kineties in the curves of the oral bulge.

Delivering cognitive therapy to people with psychosis in a community mental health setting: an effectiveness study

OBJECTIVE

Cognitive therapy (CT) has been shown to be an efficacious treatment for persistent psychotic symptoms. However, there is some debate regarding whether this is transportable to real life clinical settings. This study aimed to evaluate the effectiveness of CT for psychosis in a community mental health team (CMHT) setting.

METHOD

Patients referred for CT for psychosis were naturalistically allocated (determined by the availability of a therapist) to CT or waiting-list (WL)/treatment-as-usual (TAU). Outcome assessments were performed at WL, pre-CT, post-CT and 1-year follow-up. Data from 59 patients were analysed.

RESULTS

Random effects regression analyses showed there was a significant improvement, attributable to CT, on most outcome measures, and that many of the symptomatic improvements were maintained at follow-up. Wilcoxon signed ranks tests indicated that there was a significant reduction in psychiatric hospital use following CT.

CONCLUSION

These results confirm that CT is an effective treatment for psychosis that is generalizable to a community setting.

Caldendrin but not calmodulin binds to light chain 3 of MAP1A/B: an association with the microtubule cytoskeleton highlighting exclusive binding partners for neuronal Ca(2+)-sensor proteins

Caldendrin is a neuronal Ca(2+)-sensor protein (NCS), which represents the closest homologue of calmodulin (CaM) in nerve cells. It is tightly associated with the somato-dendritic cytoskeleton of neurons and highly enriched in the postsynaptic cytomatrix. Here, we report that caldendrin specifically associates with the microtubule cytoskeleton via an interaction with light chain 3 (LC3), a microtubule component with sequence homology to the GABAA receptor-associated protein (GABARAP), which is, like LC3, probably involved in cellular transport processes. Interestingly, two binding sites exist in LC3 for caldendrin from which only one exhibits a strict Ca(2+)-dependency for the interaction to take place but both require the presence of the first two EF-hands of caldendrin. CaM, however, is not capable of binding to LC3 at both sites despite its high degree of primary structure similarity with caldendrin. Computer modelling suggests that this might be explained by an altered distribution of surface charges at the first two EF-hands rendering each molecule, in principle, specific for a discrete set of binding partners. These findings provide molecular evidence that NCS can transduce signals to a specific target interaction irrespective of Ca(2+)-concentrations and CaM-levels.

Rearrangement of the retino-collicular projection after partial optic nerve crush in the adult rat

The establishment of retino-collicular topography is a well-investigated model of axon pathfinding and it was believed that this topography is irreversibly fixed throughout life. We now report that, after partial crush of the adult rat optic nerve, the anterograde transport of intravitreally-injected tracers via axons of surviving retinal ganglion cells (RGC) in all retinal quadrants is confined to the rostro-medial part of the superior colliculus (SC). This indicates that the retino-collicular topography is rearranged after partial crush of the adult rat optic nerve. The reorganization starts in the injured optic nerve where surviving axonal fibres are demyelinized and bundled in the periphery of the optic nerve distal to the crush site. This is followed by a displacement of surviving axons to the medial part of the optic tract (OT) within 2 weeks. The infiltration of macrophages with the subsequent production of tumour necrosis factor-alpha at the lesion site is a prerequisite for the altered retino-collicular projection as blockade of tumour necrosis factor-alpha signalling with the neutralizing antibody Infliximab abolishes reorganization in the SC and lateralization of RGC axons in the optic nerve and OT. This suggests that optic nerve inflammation is necessary for a progressive bundling of surviving RGC axons, probably via clearance of cellular debris which, in turn, may lead to a redistribution of RGC axons to the medial OT and rostro-medial SC.

Diagnostic and neural analysis of skin cancer (DANAOS). A multicentre study for collection and computer-aided analysis of data from pigmented skin lesions using digital dermoscopy

BACKGROUND

Early detection of melanomas by means of diverse screening campaigns is an important step towards a reduction in mortality. Computer-aided analysis of digital images obtained by dermoscopy has been reported to be an accurate, practical and time-saving tool for the evaluation of pigmented skin lesions (PSLs). A prototype for the computer-aided diagnosis of PSLs using artificial neural networks (NNs) has recently been developed: diagnostic and neural analysis of skin cancer (DANAOS).

OBJECTIVES

To demonstrate the accuracy of PSL diagnosis by the DANAOS expert system, a multicentre study on a diverse multinational population was conducted.

METHODS

A calibrated camera system was developed and used to collect images of PSLs in a multicentre study in 13 dermatology centres in nine European countries. The dataset was used to train an NN expert system for the computer-aided diagnosis of melanoma. We analysed different aspects of the data collection and its influence on the performance of the expert system. The NN expert system was trained with a dataset of 2218 dermoscopic images of PSLs.

RESULTS

The resulting expert system showed a performance similar to that of dermatologists as published in the literature. The performance depended on the size and quality of the database and its selection.

CONCLUSIONS

The need for a large database, the usefulness of multicentre data collection, as well as the benefit of a representative collection of cases from clinical practice, were demonstrated in this trial. Images that were difficult to classify using the NN expert system were not identical to those found difficult to classify by clinicians. We suggest therefore that the combination of clinician and computer may potentially increase the accuracy of PSL diagnosis. This may result in improved detection of melanoma and a reduction in unnecessary excisions.

[The "classical" macrophage marker CD68 is strongly expressed in primary human fibroblasts]

AIM

Monoclonal antibodies against the human homologue of mouse macrosialin, CD68, are generally commercialized as markers for human monocytes and macrophages. Indeed, CD68 is considered as a selective marker for human myeloid cells, although several previous immunohistochemical studies indicate that some antibody clones also react with other hematopoietic and non-hematopoietic cell types. The aim of our study was to verify these observations and to evaluate the reliability of CD68 as a macrophage marker.

METHODS

We investigated protein and RNA expression of CD68 in various fibroblast types and carcinoma cell lines as compared to monocytes and macrophages using immunohistochemistry, flow cytometry, and specific RT-PCR. Different monoclonal antibody clones against CD68 were applied including KP-1 and EBM11.

RESULTS

As expected, the intensity of immunohistochemical and flow cytometric CD68 staining was dependent on both the antibody clone and the fixation procedure. However, fibroblasts isolated from normal skin, normal breast, breast tumor tissue, and osteoarthritis synovia clearly expressed CD68 protein at levels comparable to macrophages. The specificity of CD68 expression in fibroblasts was verified by RT-PCR which also showed some tumor cell types to express CD68 mRNA.

CONCLUSION

Our findings clearly demonstrate that the expression of CD68 is not restricted to the macrophage lineage. This is highly relevant for experimental and diagnostic purposes, since anti CD68 antibodies cannot be accepted without reservations for the discrimination of myeloid cells and fibroblasts even in paraffin sections after formalin fixation.

Rho family small GTPases control migration of hematopoietic progenitor cells into multicellular spheroids of bone marrow stroma cells

Seeding of hematopoietic progenitor cells (HPC) into the bone marrow requires a complex interaction between cell membrane and adhesion systems and cell signaling pathways. We established a multicellular, spheroid coculture model to study HPC migration in a three-dimensional stromal environment. Here, entry of primary CD34(+) cells into stroma cell spheroids was independent of the integrins very late antigen (VLA)-4, VLA-5, lymphocyte function-associated antigen-1, and the chemokine receptor CXCR4. Experiments using a panel of bacterial toxins selectively targeting key regulators of cellular locomotion, the Rho family small GTPases Rho, Rac, and Cdc42, revealed a considerable reduction or even abrogation of TF-1 cell migration without an increase of apoptosis or impairment of proliferation. Pertussis toxin, an inhibitor of Galpha(i) proteins, showed a similar effect. In some in vitro invasion assays, phosphatidylinositol-3 kinase (PI-3K) was shown to mediate Rac- and Cdc42-induced cell motility and invasion. However, inhibition of the PI-3K pathway by LY294002 did not impair TF-1 cell migration in our three-dimensional model system.

Activation of lymphocytes inhibits human monocyte to macrophage differentiation

Tissue macrophages (MAC) differentiate from circulating blood monocytes (MO) during a maturation step that is of crucial importance for their functional competence. In vitro a similar process of maturation can be observed, if MO are cultured in the presence of serum. In the work presented here, we show that activated lymphocytes can interfere with MAC differentiation. Resting lymphocytes have only marginal influence upon MO to MAC transition in vitro. However, if cells are activated by the lectins PWM or ConA or by double-stranded RNA (polyinosinic-polycytidylic acid, pI:C), normal MAC maturation is suppressed: MO stay small and do not acquire MAC maturation-associated surface molecules like carboxypeptidase M (CPM, determined by antibody MAX.1) or CD84 (determined by antibody MAX.3). This phenomenon can be induced by small numbers of lymphocytes and can be transmitted by soluble factors in cultures stimulated with ConA or PWM. IFN-gamma is present in these conditioned media and partially suppresses MAC maturation but cannot fully substitute for the conditioned media. On the contrary, in pI:C stimulated cultures, suppression of MAC differentiation is dependent on cell-cell contact. In conclusion, activated lymphocytes are able to suppress the terminal differentiation of MAC by several pathways depending on the mode of lymphocyte stimulation.

Monocyte differentiation in intestine-like macrophage phenotype induced by epithelial cells

Macrophages in normal colonic mucosa show a specific and distinct phenotype with low expression of the typical monocyte/macrophage surface antigens CD14, CD16, and CD11b and T-cell costimulatory molecules. A method for the in vitro induction of a macrophage phenotype similar to this intestinal phenotype is presented. Multicellular spheroids (MCSs) of intestinal epithelial cell (IEC) and control cell lines were cocultured with elutriated monocytes. Surface antigen expression was analyzed by immunohistochemistry and flow cytometry. Interleukin (IL)-1beta mRNA was measured by quantitative PCR. Monocytes adhered and infiltrated the MCSs within 24 h. In the MCSs of all IEC lines, the typical monocyte/macrophage surface antigens CD14, CD16, CD11b, and CD11c, which are detectable after 24 h of coculture by immunohistochemistry and flow cytometry, were down-regulated after 7 days (e.g., for CD14 at 24 h, expression was 86% of CD33+ cells; at day 7, it was 11%). A clear decrease of lipopolysaccharide (LPS)-stimulated IL-1beta transcription in monocytes cocultured with IEC MCSs could be observed during the 7-day period. For the first time an intestine-like macrophage-phenotype could be induced in vitro. Interactions with IECs play an essential role during this differentiation, which is of functional relevance, e.g., for LPS-induced cytokine secretion.

Analysis of cellular factors influencing the replication of human immunodeficiency virus type I in human macrophages derived from blood of different healthy donors

We analyzed parameters influencing HIV-1 infectibility of cells of the monocyte/macrophage lineage (MO/MAC) isolated from different healthy donors. The proportion of in vitro-infected cells and replication kinetics in different donor MAC ranged from 0.03 to 99% p24 antigen-positive MAC and from undetectable RT activity up to 5 x 10(6) cpm/ml/90 min, respectively. As a quantitative measurement for HIV-1 susceptibility of donor MO/MAC, we determined TCID(50) values of defined virus stocks which varied up to 3000-fold depending on the donor MAC used for titration. As host factors which may influence the viral infection we determined the expression of virus receptors CD4, CCR5, CXCR4, and CCR3 as well as the secretion of the natural ligands of CCR5, which altogether showed no correlation with HIV-1 infectibility of the cells. Moreover, other MO-derived secretory factors which might affect viral infection of these cells could be excluded. Furthermore, expression of maturation-related antigens CD14, CD16, HLA-DR, and MAX.1/CPM was determined. Analysis of the reverse transcription process revealed that restricted HIV-1 infection was reflected by highly reduced or even undetectable full-length HIV-1 DNA formation, although early and intermediate transcripts appeared, suggesting that viral replication is blocked after entry at the level of early reverse transcription.

Molecular cloning and characterization of a human metalloprotease disintegrin--a novel marker for dendritic cell differentiation

The 1alpha,25-dihydroxyvitamin D(3) (1,25- [OH](2)VD(3)) modulates the differentiation of monocytic cell lines and monocytes (MOs) in vitro. Up to now several target genes of 1,25(OH)(2)VD(3) have been described in monocytic cell lines; however, little is known about target genes in primary MOs. With the Differential Display technique, we found a transcript up-regulated by 1,25(OH)(2)VD(3) in short-term cultured human blood MOs, which we called MADDAM (metalloprotease and disintegrin dendritic antigen marker; EMBL/GenBank/DDBJ accession no. Y13786). Northern blot analysis confirmed this result and revealed a signal of MADDAM messenger RNA (mRNA) at about 7.5 kilobases (kb). Long-term culture (more than 20 hours) of MOs during macrophage (MAC) differentiation led to a rapid and complete down-regulation of MADDAM expression. In contrast, MADDAM expression was maintained in MOs differentiated along the dendritic cell (DC) pathway and induced in CD34(+)-derived DCs. In addition, in situ hybridization revealed signals of MADDAM mRNA in follicles of human lymph nodes and MADDAM mRNA was detected in freshly isolated human blood-DCs by reverse transcription-polymerase chain reaction (RT-PCR). By means of a database search, we found that MADDAM is a member of the ADAM (a metalloprotease and disintegrin) family, the human homologue to murine meltrin-beta (ADAM 19). From these data, we conclude that MADDAM is an important marker for the differentiation and characterization of DCs and the distinction between MACs and DCs. (Blood. 2000;96:732-739)

Comparative analysis of integrin expression on monocyte-derived macrophages and monocyte-derived dendritic cells

Both macrophages (MAC) and dendritic cells (DC) are members of the mononuclear phagocyte system (MPS) with monocytes (MO) as common precursor cells. Cells of the MPS are able to take up, process and present antigens to T lymphocytes, thereby inducing a primary or secondary immune response. Adhesion molecules are of crucial importance for the interaction of antigen-presenting cells with immune cells, especially T lymphocytes. By representational difference analysis, we identified CD49c (VLA-3), a member of the beta1-integrin family of adhesion receptors, as differentiation-associated antigen in MO-derived MAC. In contrast, MO-derived DC did not express CD49c mRNA. These data prompted us to compare the integrin expression pattern of MAC and DC. Both cell types showed a low expression of the alpha-chains of the beta1-integrins CD49a, CD49b, CD49d and CD49e, whereas a marked difference was observed for CD49c and CD49f. Expression of both integrins increased during MO to MAC differentiation, but was not detectable on DC. In parallel the beta1-chain (CD29) was clearly up-regulated during MO to MAC differentiation but was only weakly expressed on DC. On the other hand, the beta2-integrins CD11a, CD11b, CD11c and CD18 were all expressed on MAC and DC. Beside their role in cell-cell interaction and adhesion, beta2-integrins are also known as possible binding molecules for bacteria and lipopolysaccharide (LPS), especially for high LPS concentrations. Therefore we investigated the LPS response of MAC versus DC in terms of tumour necrosis factor-alpha (TNF-alpha) release. DC were less responsive to low doses of LPS, which can easily be explained by the very low CD14 expression on DC compared for MAC. In contrast, the TNF-alpha response was comparable to MAC when DC were stimulated with high LPS concentrations. Our results show a specific, differentiation-dependent pattern of beta1- and beta2-integrin expression on in vitro-generated MAC and DC. We suggest that the high expression of CD11/CD18 on DC could be involved in the LPS binding of DC. As LPS is not only an activation but also a differentiation stimulus for DC, the expression of CD11/CD18 on DC may be important for the successful maturation of DC and thereby the initiation of a primary immune response.

Comparative analysis of CD137 and LPS effects on monocyte activation, survival, and proliferation

CD137 (ILA/4-1BB), a member of the TNF receptor family, regulates activation, survival and proliferation of primary human monocytes. Here we compare the activities of lipopolysaccharide (LPS), a classical and potent monocyte activator to that of CD137. LPS is a more potent activator of monocytes, as evidenced by a stronger induction of the proinflammatory cytokine IL-8. However, CD137 could further increase maximal cytokine induction by LPS, which points to separate signaling pathways for LPS and CD137. Also, expression of myc was only induced by the combination of CD137 and LPS. Expression of macrophage colony-stimulating factor is induced more potently by CD137, but an additive effect is obtained by the combination of CD137 and LPS. Monocyte/macrophage survival and proliferation is only induced by CD137. LPS counteracts both activities of CD137 via activation induced cell death. While LPS has a role in activation of monocytes in innate immunity, the CD137 receptor/ligand system seems to deliver an activating signal to monocyte in acquired immunity.

Expression of retinoid receptors during human monocyte differentiation in vitro

1alpha,25-dihydroxyvitamin D(3) (1,25(OH)(2)VD(3)) and retinoic acid (RA) modulate the activation of monocytes (MO) and their differentiation into macrophages (MAC). As these effects are mostly mediated by heterodimers or homodimers of the specific nuclear receptors for 1,25(OH)(2)VD(3) and RA, we investigated the expression of the retinoic acid receptors (RAR) alpha, beta, and gamma and the retinoid X-receptor (RXR) alpha in MO during differentiation into MAC or dendritic cells (DC). The mRNA of all investigated receptors except RARbeta was detected in short-term cultured MO. During differentiation of MO to MAC the mRNA expression of the RA receptors decreased. In contrast, along the differentiation pathway of MO to DC, only the mRNA expression of RARgamma declined, whereas RARalpha and RXRalpha were constantly expressed at a high level. Despite the strong expression of RARalpha and RXRalpha at mRNA level in MO-derived DC, the protein expression of the receptors was low in these cells. However, MO and MO-derived MAC showed a strong expression of these receptors at protein level. This suggests that a posttranscriptional or posttranslational mechanism of receptor regulation is occurring in these cells, and in particular in the DC. The inverse regulation of RA receptor expression and protein levels between MAC and DC may control the responsiveness of these cells to 1,25(OH)(2)VD(3) and RA.

Neurotransmitters of the sympathetic nerve terminal are powerful chemoattractants for monocytes

Macrophages in lymphoid organs are in close contact to nerve terminals of the sympathetic nervous system. Hence, these cells could be targets of neuronal modulation. We studied sympathetic neurotransmitters as chemoattractants enabling the aggregation of macrophages and nerve terminals. Norepinephrine (NE), neuropeptide Y (NPY), isoproterenol (beta-adrenergic), p-aminoclonidine (alpha2-adrenergic), methoxamine (alpha1-adrenergic), and adenosine triphosphate (ATP) were used to study human monocyte and macrophage migration in 48-well Boyden chambers. NE stimulated chemotaxis of monocytes and macrophages at an optimal concentration of 10-(10) M (P < 0.025). Isoproterenol, but not p-aminoclonidine or methoxamine, induced chemotaxis of monocytes (10(-10) M, P < 0.05). In these studies, elevation of cAMP is a critical step in NE-induced chemotaxis of monocytes. NPY (10(-11) M, P < 0.05) stimulated monocyte chemotaxis as well. ATP at 10(-4) and 10(-5) M stimulated undirected cell mobility (P < 0.05). All tested neurotransmitters of the sympathetic nerve terminal were potent chemoattractants. These findings may explain the close association of nerves and macrophages in tissue and lymphoid organs and may thus be of functional relevance in neuroimmunomodulation.

Naive monocytes can trigger transendothelial migration of peripheral blood cells through the induction of endothelial tumour necrosis factor-alpha

In this manuscript we describe a potentially new mechanism by which unstimulated human monocytes activate endothelial cells (EC) through the secondary induction of endothelial tumour necrosis factor alpha (TNF-alpha). Serum free supernatants (SN) of peripheral blood mononuclear cells (PBMC) strongly induce the expression of intercellular adhesion molecule 1 (ICAM-1, CD54), vascular cell adhesion molecule 1 (VCAM-1, CD106), and endothelial-leukocyte adhesion molecule 1 (ELAM-1, CD62E) on human EC 24 and 4 h post treatment, respectively. Further characterization of the responsible subpopulation revealed the CD14+ monocytes and a monocytic cell line (MM6) to produce an endothelial activating factor (EAF). The EAF also triggers an adhesion and a transendothelial migration (TEM) of peripheral blood cells. Using neutralization with an anti TNF-alpha MoAb MAK195, EAF is not identical with TNF-alpha, but induces the expression of endothelial TNF-alpha, since MAK195 blocked TEM only when coincubated with EC, not with monocytes. Furthermore, intracellular TNF-alpha was significantly upregulated in EC after treatment with SN-MM6. Another evidence for a secondary autocrine mechanism was provided by culturing the EC with a conditioned medium of SN-MM6 treated EC. This conditioned medium induces an adhesion molecule expression and TEM in a similar way to SN-MM6 and can completely be inactivated by anti TNF-alpha. Taken together, these data may have an impact for, e.g. transplantational settings that donor monocytes may trigger an inflammatory response in the absence of further activation signals by eliciting an endogenous TNF-alpha response in the host.