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Morphine and the endogenous opioid peptide beta-endorphin exert neuromodulatory as well as immunomodulatory effects, which are transduced by mu-opioid receptors. In this report we show that stimulation with interleukin-4 induces mu-opioid receptor transcripts in human primary blood cells (T cells and polymorphonuclear leukocytes), immune cell lines (Raji, U-937, and HMEC-1), and dendritic cells. In nonstimulated immune cells this gene is silent. In addition, mu receptor transcription is up-regulated by interleukin-4 in cultures of primary rat neurons. Transient transfection experiments in Raji and SH SY5Y neuronal cells with human and rat reporter gene constructs linked the interleukin-4 effect directly to cis-active mu receptor promoter elements located at nucleotide -997 on the human gene and nucleotide -727 on the rat gene. The interleukin-4 response elements function orientation independently. They bind STAT6 transcription factors as shown by electrophoretic mobility shift assays. In the human gene, a single nucleotide polymorphism within the interleukin-4 response element reduces the trans-activating potential of this element by 50%, which may affect the phenotype of persons carrying this variation. These findings provide a molecular basis for understanding bidirectional interactions between the opioid system and the immune system.

A palladium(II)-catalyzed hydroxycyclization-carbonylation-lactonization sequence with appropriate pent-4-ene-1,3-diols provides efficient access to the bicyclic gamma-lactones, 5-n-butyl- and 5-n-hexyltetrahydrofuro-[3,2-b]furan-2(3H)-ones (3) and (4), respectively, in both racemic and enantiomeric forms. Some of the substrate pent-4-ene-1,3-diols of high enantiomeric excess (ee) have been derived from racemic terminal epoxides by hydrolytic kinetic resolution (HKR) using cobalt (III)-salen complexes. (9Z,12R)-(+)-Ricinoleic acid also serves as a "chiral pool" source of other pent-4-ene-1,3-diols. These syntheses and enantioselective gas chromatography confirm the structures and absolute stereochemistry of the lactones in some species of parasitic wasps (Hymenoptera: Braconidae). The highly abundant 5-n-hexyltetrahydrofuro-[3,2-b]furan-2(3H)-one (4) in Diachasmimorpha kraussii and D. longicaudata is of high ee (>99%) with (3aR,5R,6aR) stereochemistry.

Germacrene D is considered as a precursor of many sesquiterpene hydrocarbons. We have investigated the acid catalyzed as well as the photochemically and thermally induced rearrangement processes of germacrene D isolated from several Solidago species, which contain both enantiomers of germacrene D. Enantiomeric mixtures of sesquiterpenes of the cadinane, eudesmane (selinane), oppositane, axane, isodaucane, and bourbonane group as well as isogermacrene D were identified as main products and made available as reference compounds for structure investigations and stereochemical assignments of plant constituents. Delta-amorphene, one of the rearrangement products, was identified as a natural product for the first time. The absolute configuration of gamma-amorphene was revised by correlation with the absolute configuration of germacrene D. The mechanisms of the rearrangement reactions are discussed.

Background: The physiology of hyperacute rejection of pig lung by human blood and the role of antispecies antibody and complement in this phenomenon have not previously been characterized., Methods: Human blood was perfused through an ex vivo pig heart-lung preparation. In the treatment groups, blood was either unmodified or modified to deplete alternative pathway complement (heat treatment), anti-pig antibody, or both. Control experiments were performed with unmodified and heat-treated pig blood. Physiologic parameters, organ survival, and immunohistology were the primary outcome measures assessed., Results: Pig lung was consistently damaged by human blood within 45 min (median 20 min), as evidenced by elevated pulmonary vascular resistance and parenchymal injury. Immunohistologic studies of perfused lungs showed prominent deposition of IgM and classical pathway component, C4, and weaker deposition of alternative pathway component, properdin. Heat treatment did not impede the rise in pulmonary vascular resistance or significantly prolong survival. Depletion of anti-pig antibody prolonged survival (median 90 min) and attenuated the rise in pulmonary vascular resistance. Antibody absorption, combined with heat treatment of plasma, prevented the elevation in pulmonary vascular resistance and yielded median graft survival (210 min) similar to pig blood perfusion (approximately 240 min)., Conclusions: These results show that elevated pulmonary vascular resistance and pulmonary parenchymal injury are mediated at least in part by antispecies antibody and heat-sensitive pathways. They are consistent with the hypothesis that complement activation contributes significantly to acute lung damage in the pig-to-human species combination.

Background: Hyperacute rejection currently prevents clinical application of discordant lung xenografts. Pigs transgenic for human regulators of complement activation offer one promising potential solution to this problem., Methods: Using fresh human blood in an ex vivo lung perfusion model, we studied eight different strains of pigs transgenic for human decay accelerating factor. Survival (by blood flow and gas transfer criteria) were correlated with immunohistologic evidence of pulmonary human decay accelerating factor expression and complement activation., Results: With human blood perfusion, blood flow through the unmodified pig lung rapidly falls and is not restored by continuous infusion or high-dose bolus of prostacyclin. Airway pressure also rises rapidly and is followed promptly by loss of gas transfer. Four of the transgenic pig strains showed no difference from this pattern. Immunohistochemistry for human decay accelerating factor revealed low or no pulmonary expression in these lungs. In contrast, two of five transgenic pig lungs that had significant decay accelerating factor expression demonstrated recovery of pulmonary blood flow within 1 hour, and rejection was delayed, from less than 20 minutes in controls to about 1 hour. Complement activation, particularly the alternative pathway, was inhibited in lungs with high levels of endothelial decay accelerating factor expression., Conclusions: Lungs from some strains of pig transgenic for human decay accelerating factor demonstrate incomplete physiologic and histologic protection from hyperacute rejection. Although complement-independent pathogenic mechanisms may present a formidable obstacle, pig lungs transgenic for human complement regulatory proteins may facilitate discordant lung transplantation in human beings.

The airway epithelial cell of the lower respiratory tract is the primary host target cell for respiratory syncytial virus (RSV) infection. To estimate whether infected epithelial cells contribute to the inflammatory host response observed during the acute infection phase we analyzed the cell surface expression of intercellular adhesion molecule-1 (ICAM-1, CD54) on human bronchial epithelial cells (A549) following RSV infection and cytokine priming. The epithelial cells constitutively expressed ICAM-1. The ICAM-1 surface expression was significantly up-regulated up to 72 h post RSV infection. In addition, cytokine priming with tumor necrosis factor alpha (TNF-alpha), interferon-gammma (IFN-gamma), or interleukin-1 alpha/beta (IL-1alpha/beta) induced an enhanced ICAM-1 expression on noninfected as well as on RSV-infected epithelial cells. As early as 24 h post RSV infection and cytokine priming, respectively, the maximum of ICAM-1-expressing cells was observed. In contrast, the maximal ICAM-1 up-regulation per cell was measured 24 h later, e.g., after 48 h of culture. Cytokine priming with IL-3, IL-6, granulocyte-macrophage colony-stimulating factor (GM-CSF), or granulocyte colony-stimulating factor (G-CSF) did not lead to a significant increase of ICAM-1 expression either on RSV-infected or on noninfected A549 cells up to 72 h of culture time. Performed signal transduction experiments, e.g. [alpha-32P]GTP-binding blot analysis, revealed that low-molecular-weight GTP-binding proteins possess an enhanced GTP-binding capacity in RSV-infected A549 cells.

Prominent components of vascularized xenograft rejection such as platelet activation and microvascular thrombosis may be dependent upon thrombin generation in vivo. To study potential therapeutic benefits of a synthetic low-molecular-weight thrombin inhibitor, SDZ MTH 958, in hyperacute porcine heart rejection by human blood ex vivo, a working model of hyperacute rejection of porcine by fresh, heparinized (6 microM/ml) human blood with or without 1 microM SDZ MTH 958 was used. Thrombin-antithrombin complexes (TAT) and prothrombin fragment F1.2 levels as markers of thrombin activation were determined, and biopsies from rejected hearts were analyzed by immunohistopathology. Control porcine hearts (n=8) underwent a rapid and consistent decline in cardiac output, ceasing function by 60 min. Experimental cardiac output values of 14 ml/g (SEM 1.2) were significantly higher than seen in controls (5 ml/g SEM 0.6) after 5 min of cardiac work, and prolonged survival times up to 120 min were noted (P<0.05). Activity of SDZ MTH 958 was confirmed by functional assays throughout perfusion. Levels of TAT and F1.2 increased consistently in control samples when compared with plasma samples containing SDZ MTH 958. Immunohistopathological examination confirmed diminished fibrin deposition, reduced leukocyte adherence to endothelium, impaired diapedesis and less tissue necrosis in the hearts perfused with SDZ MTH 958. SDZ MTH 958, in this xenoperfusion model, prolonged survival, enhanced function of the explanted organ, and improved histological features at the time of rejection. Effective and specific antagonism of thrombin may be useful as an adjunct therapy to complement inhibition for xenograft rejection

New intermediates associated with nikkomycin biosynthesis, called nikkomycins SZ, SX, SoZ and SoX, were isolated and characterized from the culture broth of Streptomyces tendae Tü 901/S 2566. They are analogues to octosyl acids, shunt metabolites of polyoxin biosynthesis. The decreasing amounts of nikkomycins SZ and SX, produced in the culture medium, shows a significant correlation to the increasing amounts of the biologically active nikkomycins Z and X, dependent on the increasing concentration of iron.

Lipoxygenase factors of arachidonic acid (mono- and di-Hetes) are not only mediators but also modulators of inflammatory reactions. They have chemotactic and spasmogenic properties; the latter are similar to those induced by the slow reacting-substance of anaphylaxis (SRS-A). The eosinophil chemotactic factor has been identified as a lipoxygenase product. Among the chemically mono- and di-Hetes the 5-S-12-R di-Hete (LTB4) and the 5-S 12S di-Hete demonstrated the most pronounced eosinophil chemotactic activity. The phospholipase-arachidonic acid sequence is involved in the IgE induced activation and secretion of human basophils. With arachidonic acid analogs the lipoxygenase transformation pathway is inhibited.

It is well established that IgE-antibodies against allergens are involved in allergic diseases. Thus, the regulation of IgE antibody synthesis appears to be a fundamental approach to its treatment. The mechanisms of the IgE-antibody response are somehow different from IgG production. It appears that the immunocompetent cells involved are distinct and exert a different susceptibility with regard to IgE- and IgG antibody production. A more precise under-standing of the cellular processes involved in IgE-antibody production will lead to novel immunotherapeutic approaches of allergic disease processes.

A method of optical filtering in order to provide for enhancement of x-ray images whose quality has been degraded because of the use of extended x-ray sources (penumbra effect) is considered. This method employs spatial filtering techniques in a coherent optical system. A description of the penumbra effect follows from the mathematical description of imaging in incoherent optical systems. With the use of this model the degradation can be described in terms of the effect of the extended source on the frequency content of the resulting image. This leads to a precise definition of the ideal filter in terms of the spatial intensity distribution of the source and a general description of the filtering operations which will be required in all cases, independent of the exact source distribution. It is shown that the form of the ideal filter is such that the same optical system used in the filtering process is ideally suited for generating filters with, approximately, the required transmission characteristics. Experi mental results are presented.