Dismal prognosis of Pneumocystis jirovecii pneumonia in patients with multiple myeloma

Patients with multiple myeloma (MM) are at high risk for infections, including opportunistic infections such as Pneumocystis jirovecii pneumonia (PJP). We conducted a retrospective analysis of patients with MM developing PJP over a 6-year period between January 2016 and December 2021 at the University Hospital of Würzburg by screening cases of microbiologically documented PJP. A total of 201 positive results for P. jirovecii in respiratory specimens were retrospectively retrieved through our microbiology database. Of these cases, 13 patients with MM fulfilled the definition of probable PJP according to EORTC fungal disease definitions. We observed two peaks in PJP incidence, one after stem cell transplantation during first-line treatment (n = 5) and the other in heavily pretreated patients with six or more prior lines of therapy (n = 6). There was high morbidity with nine (69%) patients admitted to the ICU, seven of whom (78%) required mechanical ventilation, and high mortality (62%, n = 8). Notably, only two of the 13 patients (15%) had received PJP prophylaxis. The main reason for discontinuation of prophylaxis with trimethoprim-sulfamethoxazole was grade IV neutropenia. The observed morbidity and mortality of PJP in MM patients are significant and even higher than reported for patients with other hematologic malignancies. According to most current guidelines, the use of prophylaxis would have been clearly recommended in no more than three (23%) of the 13 patients. This illustrates the need to critically reconsider the indications for PJP prophylaxis, which remain incompletely defined.

Fourier-transform infrared spectroscopy for typing of vancomycin-resistant Enterococcus faecium: performance analysis and outbreak investigation

Vancomycin-resistant Enterococci, mainly Enterococcus faecium (VREfm), are causing nosocomial infections and outbreaks. Bacterial typing methods are used to assist in outbreak investigations. Most of them, especially genotypic methods like multi-locus sequence typing (MLST), whole genome sequencing (WGS), or pulsed-field gel electrophoresis, are quite expensive and time-consuming. Fourier-transform infrared (FT-IR) spectroscopy assesses the biochemical composition of bacteria, such as carboxyl groups in polysaccharides. It is an affordable technique and has a faster turnaround time. Thus, the aim of this study was to evaluate FT-IR spectroscopy for VREfm outbreak investigations. Basic performance requirements like reproducibility and the effects of incubation time were assessed in distinct sample sets. After determining a FT-IR spectroscopy cut-off range, the clustering agreement between FT-IR and WGS within a retrospective (n: 92 isolates) and a prospective outbreak (n: 15 isolates) was investigated. For WGS an average nucleotide identity (ANI) cut-off score of 0.999 was used. Basic performance analysis showed reproducible results. Moreover, FT-IR spectroscopy readouts showed a high agreement with WGS-ANI analysis in clinical outbreak investigations (V-measure 0.772 for the retrospective and 1.000 for the prospective outbreak). FT-IR spectroscopy had a higher discriminatory power than MLST in the outbreak investigations. After determining cut-off values to achieve optimal resolution, FT-IR spectroscopy is a promising technique to assist in outbreak investigation as an affordable, easy-to-use tool with a turnaround time of less than one day. IMPORTANCE Vancomycin-resistant Enterococci, mainly Enterococcus faecium (VREfm), are a frequent cause of nosocomial outbreaks. Several bacterial typing methods are used to track transmissions and investigate outbreaks, whereby genome-based techniques are used as a gold standard. Current methods are either expensive, time-consuming, or both. Additionally, often, specifically trained staff needs to be available. This study provides insight into the use of Fourier-transform infrared (FT-IR) spectroscopy, an affordable, easy-to-use tool with a short turnaround time as a typing method for VREfm. By assessing clinical samples, this work demonstrates promising results for species discrimination and reproducibility. FT-IR spectrosopy shows a high level of agreement in the analysis of VREfm outbreaks in comparison with whole genome sequencing-based methods.

P10.15.B Next generation drug screening platform: generation of patient-derived cells forex vivo drug response studies of gliomas

Background

Precision oncology aims to provide individual treatment options for each patient. In this regard, ex vivo drug screening systems have the potential to improve clinical outcomes. Traditionally, cancer drugs are tested on long-term cultured cancer cell line models, but cell lines cannot represent an individual patient from a clinic and are biologically too distinct to be informative for drug screening purposes. Drug screening systems of tumor cells usually rely on viability assays and correlations to genomic alterations. Beside genomic alterations, the cellular metabolism is significantly altered during tumor growth, tumor cell proliferation and tumor cell resistance development. Here we aim to establish a drug screening platform using tumor cells derived directly from the individual patient glial tumor, create patient derived tumor cells (PDCs) and combine the outcomes from standardized viability- and genetic-assays with a new developed metabolomics platform.

Material and Methods

Fresh native tissue from both low- and high-grade glioma are collected. Tumor tissue is used for NMR-based metabolomic analyses and targeted sequencing based genomic analyses as well as PDC isolation using mechanical and enzymatic tissue dissociation. To preserve the original tumor similarity, tissue is short term cultured for two weeks, and PDCs are seeded and treated with a panel of clinical- and preclinical drugs followed by viability assessment, sequencing and metabolomic profiling.

Results

Culturing of PDCs is successful in ≥85% of patient cases, provided that at least 2 g of tumor are available. The automatized high throughput ex vivo drug response helps to identify potential drug candidates which might become relevant for therapeutic approaches in future. Further, it is possible to distinguish between IDH1-wild type and IDH1-mutant glial tumors based on the metabolomic profile, which is confirmed by immunohistochemical staining and molecular analysis of IDH1 R132H-mutation. Strong metabolomic variations have been identified, including GABA, lactate, and myo-inositol levels between tumor and healthy tissue. Data retrieved by the systematic evaluation is retrospectively associated with the clinical course of the patients.

Conclusion

Entangling drug screening and genetic assays with metabolomic profiling of glial tumors enriches the information about cellular drug response and paves the way for future clinical studies and better understanding of underlying drug resistance mechanisms in gliomas.

Disclosure

Funding: K1 COMET Competence Centre CBmed, funded by the Federal Ministry of Transport, Innovation and Technology; the Federal Ministry of Science, Research and Economy, Land Steiermark (Dep. 12, Business and Innovation), the Styrian Business Promotion Agency (SFG), and the Vienna Business Agency. COMET is executed by the Austrian Research Promotion Agency (FFG).

[Update on collaborative autopsy-based research in German pathology, neuropathology, and forensic medicine]

BACKGROUND

Autopsies are a valuable tool for understanding disease, including COVID-19.

MATERIALS AND METHODS

The German Registry of COVID-19 Autopsies (DeRegCOVID), established in April 2020, serves as the electronic backbone of the National Autopsy Network (NATON), launched in early 2022 following DEFEAT PANDEMIcs.

RESULTS

The NATON consortium's interconnected, collaborative autopsy research is enabled by an unprecedented collaboration of 138 individuals at more than 35 German university and non-university autopsy centers through which pathology, neuropathology, and forensic medicine autopsy data including data on biomaterials are collected in DeRegCOVID and tissue-based research and methods development are conducted. More than 145 publications have now emerged from participating autopsy centers, highlighting various basic science and clinical aspects of COVID-19, such as thromboembolic events, organ tropism, SARS-CoV‑2 detection methods, and infectivity of SARS-CoV-2 at autopsy.

CONCLUSIONS

Participating centers have demonstrated the high value of autopsy and autopsy-derived data and biomaterials to modern medicine. The planned long-term continuation and further development of the registry and network, as well as the open and participatory design, will allow the involvement of all interested partners.

[Learning from coding data-surgical treatment of benign prostatic syndrome : Big data for BPS]

Benign prostatic syndrome (BPS) is one of the most common urological diseases. Currently, there are numerous surgical methods to treat BPS. The digitalisation of medicine enables new study approaches in healthcare research using digital data from individual treatment pathways. In the present work, BPS-specific longitudinal trend analyses were performed. Treatment-related figures, both with regard to the therapy methods and predefined patient cohorts, could be examined after validating the datasets. This meant that information on relevant characteristics of surgical BPS treatment could be read and calculations made that reflect the overall impact of these processes. In the future, it is expected that increasingly comprehensive, higher-quality digital datasets on different clinical pictures will be available for analytical purposes. Intensification of research projects in this field is desirable. The results thus obtained enable further optimisation steps of certain treatment actions and provide important key figures for the strategy development of a medical facility.

Spontaneous electron emission vs dissociation in internally hot silver dimer anions

Referring to a recent experiment, we theoretically study the process of a two-channel decay of the diatomic silver anion (Ag₂ ^-), namely, the spontaneous electron ejection giving Ag₂ + e^- and the dissociation leading to Ag^- + Ag. The ground state potential energy curves of the silver molecules of diatomic neutral and negative ions were calculated using proper pseudo-potentials and atomic basis sets. We also estimated the non-adiabatic electronic coupling between the ground state of Ag₂ ^- and the ground state of Ag₂ + e^-, which, in turn, allowed us to estimate the minimal and mean values of the electron autodetachment lifetimes. The relative energies of the rovibrational levels allow the description of the spontaneous electron emission process, while the description of the rotational dissociation is treated with the quantum dynamics method as well as time-independent methods. The results of our calculations are verified by comparison with the experimental data.

Phosphatidylethanolamine positively regulates autophagy and longevity

Autophagy is a cellular recycling program that retards ageing by efficiently eliminating damaged and potentially harmful organelles and intracellular protein aggregates. Here, we show that the abundance of phosphatidylethanolamine (PE) positively regulates autophagy. Reduction of intracellular PE levels by knocking out either of the two yeast phosphatidylserine decarboxylases (PSD) accelerated chronological ageing-associated production of reactive oxygen species and death. Conversely, the artificial increase of intracellular PE levels, by provision of its precursor ethanolamine or by overexpression of the PE-generating enzyme Psd1, significantly increased autophagic flux, both in yeast and in mammalian cell culture. Importantly administration of ethanolamine was sufficient to extend the lifespan of yeast (Saccharomyces cerevisiae), mammalian cells (U2OS, H4) and flies (Drosophila melanogaster). We thus postulate that the availability of PE may constitute a bottleneck for functional autophagy and that organismal life or healthspan could be positively influenced by the consumption of ethanolamine-rich food.

Effects of acupuncture needle penetration on motor system excitability

OBJECTIVES

Transcranial magnetic stimulation (TMS) studies reported changes in motor evoked potential amplitude after acupuncture needling both at traditional acupoints and non-acupoints. However, the effects of needle penetration per se have not yet been investigated with TMS. The present study aimed at exploring effects of deep manual acupuncture needling compared to a state-of-the-art, non-penetrating control condition on several standard TMS measures of motor system excitability.

METHODS

Twenty healthy volunteers received both verum and sham acupuncture applied at the acupoint GB 34 near the right knee, using a crossover design. A needle with a retractable tip ("Streitberger needle") was used as sham condition to minimize non-specific effects. TMS parameters (resting motor threshold, active motor threshold, cortical silent period, short intracortical inhibition, and intracortical facilitation) were calculated from the abductor digiti minimi (ADM) of both hands 15 min before and after needling by a researcher blind to the treatment condition.

RESULTS

Verum compared to sham acupuncture significantly increased resting motor threshold. No significant treatment effect was found for any other measure, though cortical silent period and intracortical facilitation showed trends to increase in the hemisphere contralateral to the needling site after verum acupuncture.

CONCLUSIONS

These results suggest a subtle but specific inhibitory effect of acupuncture needle penetration at acupoint GB 34 on motor system excitability. Further investigations should be performed with a particular emphasis on the measurements of resting motor threshold, cortical silent periods and intracortical facilitation.

Macrophage migration inhibitory factor (MIF) promotes cell survival by activation of the Akt pathway and role for CSN5/JAB1 in the control of autocrine MIF activity

The phosphoinositide-3-kinase (PI3K)/Akt signaling pathway plays an important role in cell survival and the development of cancer. Macrophage migration inhibitory factor (MIF) is a critical inflammatory cytokine that was recently associated with tumorigenesis and that potently inhibits apoptosis. This may involve inhibition of p53-dependent genes, but the initiating molecular mechanism of how MIF controls survival/apoptosis is unknown. Here, we show that MIF prevents apoptosis and promotes tumor cell survival by directly activating the Akt pathway. MIF enhanced Akt activity in primary and immortalized fibroblasts (MEF and NIH/3T3), HeLa cervix carcinoma cells and various breast cancer cell lines. Activation was abolished by kinase inhibitors Ly294002 and PP2 and in Src/Yes/Fyn(SYF)(-/-) and CD74(-/-)(MEFs), while being enhanced in CD74-overexpressing MEFs, demonstrating that the MIF-induced Akt pathway encompasses signaling through the MIF receptor CD74 and the upstream kinases Src and PI3K. Akt was activated by exogenous rMIF and autocrine MIF action, as revealed by experiments in MIF(-/-)MEFs and antibody blockade. siRNA knockdown of CSN5/JAB1, a tumor marker and MIF-binding protein, showed that JAB1 controls autocrine MIF-mediated Akt signaling by inhibition of MIF secretion. Akt activation by MIF led to phosphorylation of the proapoptotic proteins BAD and Foxo3a. Apoptosis inhibition by MIF was functionally associated with Akt activation as it was abolished by overexpression of the Akt pathway inhibitor PTEN and occurred independently of p53. This was shown by studying DNA damage-induced apoptosis in fibroblasts, the Fas death pathway in HeLa cells that do not express functional p53, and etoposide-induced apoptosis in breast carcinoma cells expressing mutant p53. Importantly, dependence of breast cancer cell survival on MIF correlated with Akt activation and the PTEN status of these cells. Thus, MIF can directly promote cell survival through activation of the PI3K/Akt pathway and this effect is critical for tumor cell survival.

First measurement of the transverse spin asymmetries of the deuteron in semi-inclusive deep inelastic scattering

First measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in 2002 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins asymmetry turns out to be compatible with zero, as does the measured Sivers asymmetry within the present statistical errors.

First results from the CERN axion solar telescope

Hypothetical axionlike particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field ("axion helioscope"), they would be transformed into x-rays with energies of a few keV. Using a decommissioned Large Hadron Collider test magnet, the CERN Axion Solar Telescope ran for about 6 months during 2003. The first results from the analysis of these data are presented here. No signal above background was observed, implying an upper limit to the axion-photon coupling g(agamma)<1.16x10(-10) GeV-1 at 95% C.L. for m(a) less, similar 0.02 eV. This limit, assumption-free, is comparable to the limit from stellar energy-loss arguments and considerably more restrictive than any previous experiment over a broad range of axion masses.

Hypernuclear fine structure in (16)(Lambda)O and the LambdaN tensor interaction

We have observed two gamma-ray transitions in (16)(Lambda)O from the 6.6 MeV excited 1(-)(2) state to both ground-state spin-doublet members (1(-)(1),0(-)) by the (K-,pi(-)gamma) reaction. We have obtained the ground-state doublet spacing to be 26.4+/-1.6(stat)+/-0.5(syst) keV and the excitation energy of the 1(-)(2) state to be 6561.7+/-1.1(stat)+/-1.7(syst) keV. The ground-state doublet spacing provides a small but nonzero strength of the tensor interaction between a Lambda and a nucleon. This is the first experimental result on the LambdaN tensor interaction.

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with reanalyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.

Evidence for quark-hadron duality in the proton spin asymmetry A1

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were scattered off a longitudinally polarized hydrogen target for values of Q2 between 1.2 and 12 GeV2 and values of W2 between 1 and 4 GeV2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable x. This finding implies that the description of A1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2 above 1.6 GeV2.

Q2 dependence of nuclear transparency for exclusive rho0 production

Exclusive coherent and incoherent electroproduction of the rho(0) meson from 1H and 14N targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon (-Q2). The ratio of 14N to 1H cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing l(c) for coherent (incoherent) rho(0) electroproduction. For fixed l(c), a rise of nuclear transparency with Q2 is observed for both coherent and incoherent rho(0) production, which is in agreement with theoretical calculations of color transparency.

Measurement of spin-transfer observables in p p-->Lambda Lambda at 1.637 GeV/c

Spin-transfer observables for p p-->Lambda Lambda have been measured using a transversely polarized frozen-spin target and a beam momentum of 1.637 GeV/c. Current models of the reaction near threshold are in good agreement with existing measurements performed with unpolarized particles in the initial state but produce conflicting predictions for the spin-transfer observables Dnn and Knn (the normal-to-normal depolarization and polarization transfer), which are measurable only with polarized target or beam. Measurements of Dnn and Knn presented here are found to be in disagreement with predictions from these models.

Antigenic and adjuvant activities of branched aliphatic oligoester (M-DL-LA) microspheres with incorporated bovine rotavirus

Branched aliphatic oligoester microspheres (msp) with incorporated rotavirus were used to induce the production of systemic and mucosal antibodies in mice. The msp with a mean diameter of 7.4 microm were prepared by the w/o/w technique. The mice were immunized intraperitoneally or orally. High ELISA titres of systemic and local IgG and IgA antibodies were indicative of rotavirus incorporation and of the adjuvant activity of msp. Oral immunization with a split dose administered on three consecutive days, resulted in the production of systemic IgG and IgA antibodies, but failed to induce the production of mucosal antibodies even if the immunization dose was increased threefold. Specific antibodies were detectable in faeces of orally immunized mice only after another triple administration of the same dose in the fourth week of the experiment. Reactions of blood serum IgG with the structural viral proteins VP4, VP6, and VP7 were demonstrated by western blotting. Both systemic, and faecal IgA antibodies were specific for the VP6 protein and the dimeric form of the glycoprotein VP4.

Hypernuclear fine structure in (9)(lambda)Be

With a germanium detector array (Hyperball), we observed two gamma-ray peaks corresponding to the two transitions (5/2(+)-->1/2(+) and 3/2(+)-->1/2(+)) in the (9)(Lambda)Be hypernucleus which was produced by the 9Be(K-,pi(-)) reaction. The energies of the gamma rays are 3029 +/- 2 +/- 1 keV and 3060 +/- 2 +/- 1 keV. The energy difference was measured to be 31.4(+2.5)(-3.6) keV, which indicates a very small Lambda-spin-dependent spin-orbit force between a Lambda and a nucleon. This is the smallest level splitting by far ever measured in a hypernucleus.

Production of (4)(double Lambda)H hypernuclei

An experiment demonstrating the production of double-Lambda hypernuclei in (K(-),K(+)) reactions on (9)Be was carried out at the D6 line in the BNL alternating-gradient synchrotron. The technique was the observation of pions produced in sequential mesonic weak decay, each pion associated with one unit of strangeness change. The results indicate the production of a significant number of the double hypernucleus (4)(double Lambda)H and the twin hypernuclei (4)(Lambda)H and (3)(Lambda)H. The relevant decay chains are discussed and a simple model of the production mechanism is presented. An implication of this experiment is that the existence of an S = -2 dibaryon more than a few MeV below the double Lambda mass is unlikely.

Observation of spin-orbit splitting in lambda single-particle states

The spin-orbit splitting of Lambda single-particle states in (13)(Lambda)C was measured. The 13C(K-,pi(-))(13)(Lambda)C reaction was used to excite both the 1/2(-) and 3/2(-) states simultaneously, which have predominantly 12C(0(+)) x p(Lambda) configuration. gamma rays from the states to the ground state were measured in coincidence with the pi(-)'s, by which ls splitting was found to be 152+/-54(stat)+/-36(syst) keV. The value is 20-30 times smaller than exhibited by the ls splitting in the nuclear shell model. This value gives us new insight into the YN interaction.

Rapid typing of Borrelia burgdorferi sensu lato species in specimens from patients with different manifestations of Lyme borreliosis

To further investigate the pathogenic potential of different Borrelia burgdorferi genospecies, specimens from 27 patients with different manifestations of Lyme borreliosis were analyzed by PCR and reverse line blotting (RLB). In samples from Lyme arthritis patients, B. burgdorferi sensu stricto was predominantly identified, while in patients with neuroborreliosis or acrodermatitis, Borrelia garinii and Borrelia afzelii, respectively, were exclusively detected. The results demonstrate that PCR-RLB is a valuable tool for epidemiological and pathogenetic studies of Lyme borreliosis.

Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle straight phi of the pion relative to the lepton scattering plane was formed for pi(+) electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sinstraight phi moment of the cross section is 0.022+/-0.005+/-0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark.

Circulating levels of matrix metalloproteinases MMP-3 and MMP-1, tissue inhibitor of metalloproteinases 1 (TIMP-1), and MMP-1/TIMP-1 complex in rheumatic disease. Correlation with clinical activity of rheumatoid arthritis versus other surrogate markers

OBJECTIVE

To investigate whether plasma levels of matrix metalloproteinases 3 (MMP-3, stromelysin), MMP-1 (collagenase), tissue inhibitor of metalloproteinases 1 (TIMP-1), and MMP1/TIMP-1 complex (MT complex) are specifically elevated in erosive joint diseases compared to nonerosive rheumatic diseases, and to assess how these markers reflect the clinical activity of rheumatoid arthritis (RA) compared to circulating cytokines and markers of connective tissue turnover as well as established variables [C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and rheumatoid factor titer].

METHODS

Plasma levels of MMP-3, MMP-1, TIMP- 1, and MT complex were determined by ELISA. One hundred fifteen patients with RA, 20 with osteoarthritis (OA), 28 with psoriasis arthritis (PsA), 24 with ankylosing spondylitis (AS), 3 groups with systemic autoimmune diseases, and 30 healthy controls were analyzed. In patients with RA routine laboratory variables, circulating inflammatory cytokines [interleukin 1 (IL-1), tumor necrosis factor-alpha (TNF-alpha), and IL-6], collagen degradation products, and markers of bone formation were determined in parallel and were correlated to 4 variables of clinical activity.

RESULTS

MMP-3 levels were markedly elevated in RA compared to controls and OA, but also in all other groups, including 26 patients with systemic lupus erythematosus (SLE). MMP-1 levels were significantly elevated in RA, but also in OA, PsA, SLE, and mixed connective tissue disease. In contrast, MT complex was elevated in RA only. TIMP-1 was not different from controls. CRP levels, MMP-3, and ESR correlated best with clinical activity of RA. In contrast, there was no correlation of IL-1 and TNF-alpha and only a weak correlation of IL-6 with clinical measures. Among variables of connective tissue turnover, only pyridinoline and deoxypyridinoline crosslinks were weakly correlated with disease activity.

CONCLUSION

Elevated MMP-3 and MMP-1 levels are not specific for RA or for erosive joint diseases in general. In contrast, elevated MT complex levels were observed in patients with RA. However, the correlation of MT-1 with clinical data was weaker than that of MMP-3. Elevated MMP-3 levels reflected disease activity of RA better than cytokine levels or markers of connective tissue turnover. However, MMP-3 levels do not exceed the association of CRP with clinical activity.

Recombinant fish neurotrophin-6 is a heparin-binding glycoprotein: implications for a role in axonal guidance

Neurotrophin-6 (NT-6) was identified in the teleost fish Xiphophorus as a new member of the neurotrophin gene family. NT-6 binds specifically the glycosaminoglycan heparin. In this study NT-6 was expressed in a stably transfected mammalian cell line, and in insect cells via a recombinant baculovirus. It was purified to homogeneity and characterized by MS and N-terminal sequencing. NT-6 from both expression systems was proteolytically processed at one of two protease cleavage motifs and was found to be glycosylated. It supported the survival of embryonic chick sensory neurons; half-maximal survival was observed at 100 ng/ml. Furthermore, NT-6 elicited neurite outgrowth in explanted embryonic dorsal root ganglia. Addition of heparin into the medium did not potentiate the activity of NT-6 in survival assays. However, when a sensory ganglion explant was cultured in a collagen gel matrix assay adjacent to a heparin bead coated with NT-6, neurite outgrowth directed towards the bead was observed. This indicated that NT-6 was slowly released from the heparin bead generating a concentration gradient of NT-6 instrumental for axonal guidance in vitro. Thus the interaction of NT-6 with heparin might not be required for the activation of the cellular receptor for NT-6 on responsive cells but rather may serve to control, in vivo, the distribution of NT-6.

Spontaneously released substance P and bradykinin from isolated guinea-pig bladder

OBJECTIVES

To investigate whether the isolated urinary bladder spontaneously releases substance P (SP) or bradykinin (BK), which can act as potent mediators of pain and inflammation of the urinary bladder, and whether peptidase inhibitors enhance peptide release.

MATERIALS AND METHODS

Urinary bladder segments (2 x 10 x 0.8-1 mm) were isolated from guinea pigs and studied in vitro; tissue contraction was assessed using force-displacement transducers and the release of peptides by specific enzyme immunoassays.

RESULTS

In the absence of any exogenous agonists, the inhibition of neutral endopeptidase and angiotensin-converting enzyme by phosphoramidon and captopril, respectively, increased the frequency and magnitude of spontaneous motility of isolated bladder strips. Phosphoramidon increased the net release of SP-like immunoreactivity (SP-LI) and captopril increased the net release of SP-LI and BK-LI, concomitant with contraction. Peptide-LI was recovered primarily from bladder mucosa and to a lesser degree from detrusor smooth muscle. Similarly, peptidase inhibitors primarily affected the bladder mucosa; phosphoramidon induced a fourfold increase in SP-LI and captopril induced a significant increase of SP-LI and BK-LI from the mucosa. Tissues contracted in response to peptidase inhibitors in the presence of atropine and indomethacin, but contraction was reduced significantly by in vitro capsaicin desensitization or removal of bladder mucosa. BK stimulated SP-LI release from mucosa but not detrusor. SP stimulated increased BK-LI release from mucosa and detrusor.

CONCLUSIONS

These findings indicate the basal release of peptide-like immunoreactivity by isolated bladder and further support the concept that peptidases located in the bladder mucosa are important in terminating the effects of endogenous peptides.

Immunogenicity of infectious bovine rhinotracheitis virus (BHV-1) proteins integrated into ISCOMs or liposomes

Dynamics and persistence of antibody responses to immunization and reimmunization of rabbits with BHV-1 ISCOMs or BHV-1 liposomes were investigated for 20 weeks and compared with those induced by a commercial vaccine against infectious bovine rhinotracheitis (IBR) or free BHV-1 protein subunits. Comparable levels of antibodies to BHV-1, determined by ELISA, were found throughout the observation period in rabbits treated with BHV-1 ISCOMs or the commercial vaccine. The immunogenicity of BHV-1 liposomes was higher than that of the free virus proteins, but lower than those of BHV-1 ISCOMs or the commercial vaccine. Virus neutralization test confirmed the best immunostimulatory effect of BHV-1 ISCOMs as far as the levels and the persistence of antibodies were concerned. The reactivities of the specific virus protein subunits with anti-BHV-1 antibodies elicited in rabbits immunized with BHV-1 ISCOMs or the commercial vaccine were compared by Western blotting. The patterns of the bands were similar, but some differences were found in their numbers and intensities.

Enhancement of antibody response to bovine herpesvirus 1 with non-specific immunostimulants

Stimulatory effects of aluminium hydroxide, lipopolysaccharide (LPS), muramyldipeptide (MDP), and empty liposomes on the antigenicity of inactivated bovine herpesvirus 1 were tested in mice. Compared with the standard effect of aluminium hydroxide, stronger antibody responses were observed in mice treated with empty liposomes or LPS alone, or a combination thereof. The strongest antibody response was recorded in mice treated with a combination of inactivated BHV-1, MDP and empty liposomes.