• The pseudomonas quinolone signal (PQS) balances life and death in Pseudomonas aeruginosa populations.

      Häussler, Susanne; Becker, Tanja; Department of Cell Biology, Helmholtz Center for Infection Research, Braunschweig, Germany. susanne.haeussler@helmholtz-hzi.de (2008)
      When environmental conditions deteriorate and become inhospitable, generic survival strategies for populations of bacteria may be to enter a dormant state that slows down metabolism, to develop a general tolerance to hostile parameters that characterize the habitat, and to impose a regime to eliminate damaged members. Here, we provide evidence that the pseudomonas quinolone signal (PQS) mediates induction of all of these phenotypes. For individual cells, PQS, an interbacterial signaling molecule of Pseudomonas aeruginosa, has both deleterious and beneficial activities: on the one hand, it acts as a pro-oxidant and sensitizes the bacteria towards oxidative and other stresses and, on the other, it efficiently induces a protective anti-oxidative stress response. We propose that this dual function fragments populations into less and more stress tolerant members which respond differentially to developing stresses in deteriorating habitats. This suggests that a little poison may be generically beneficial to populations, in promoting survival of the fittest, and in contributing to bacterial multi-cellular behavior. It further identifies PQS as an essential mediator of the shaping of the population structure of Pseudomonas and of its response to and survival in hostile environmental conditions.
    • Purification of the human fibroblast growth factor 2 using novel animal-component free materials

      Bolten, Svenja Nicolin; Knoll, Anne-Sophie; Li, Zhaopeng; Gellermann, Pia; Pepelanova, Iliyana; Rinas, Ursula; Scheper, Thomas; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Elsevier BV, 2020-08)
      This paper analyzes the use of animal-component free chromatographic materials for the efficient purifi- cation of the human fibroblast growth factor 2 (hFGF-2). hFGF-2 is produced in Escherichia coli and pu- rified via three different chromatography steps, which include a strong cation exchange chromatography as a capture step, followed by heparin affinity chromatography and an anion exchange chromatography as a polishing step. The affinity chromatography step is based on the animal-derived material heparin. Chemically produced ligands provide a viable alternative to animal-derived components in production processes, since they are characterized by a defined structure which leads to reproducible results and a broad range of applications. The alternative ligands can be assigned to adsorber of the mixed-mode chromatography (MMC) and pseudo-affinity chromatography. Eight different animal-component free materials used as adsorbers in MMC or pseudo-affinity chromatog- raphy were tested as a substitute for heparin. The MMCs were cation exchangers characterized with fur- ther functional residues. The ligands of the pseudo-affinity chromatography were heparin-like ligands which are based on heparin’s molecular structure. The alternative methods were tested as a capture step and in combination with another chromatographic step in the purification procedure of hFGF-2. In each downstream step purity, recovery and yield were analysed and compared to the conventional downstream process. Two types of MMC –the column Foresight TM Nuvia TM cPrime TM from Bio-Rad Laboratories and the col- umn HiTrap TM Capto TM MMC from GE Healthcare Life Sciences - can be regarded as effective animal- component free alternatives to the heparin - based adsorber.
    • Quantitation of large, middle and small hepatitis B surface proteins in HBeAg-positive patients treated with peginterferon alfa-2a.

      Rinker, Franziska; Bremer, Corinna M; Schröder, Kathrin; Wiegand, Steffen B; Bremer, Birgit; Manns, Michael P; Kraft, Anke R; Wedemeyer, Heiner; Yang, Lei; Pavlovic, Vedran; et al. (Wiley, 2019-11-13)
      BACKGROUND & AIMS: Hepatitis B virus (HBV) contains three viral surface proteins, large, middle and small hepatitis B surface protein (LHBs, MHBs, SHBs). Proportions of LHBs and MHBs are lower in patients with inactive versus active chronic infection. Interferon alfa may convert HBeAg-positive chronic hepatitis B (CHB) to an inactive carrier state, but prediction of sustained response is unsatisfactory. The aim of this study was to test the hypothesis that quantification of MHBs and LHBs may allow for a better prognosis of therapeutic response than total hepatitis B surface antigen (HBsAg) concentration. METHODS: HBs proteins were measured before and during peginterferon alfa-2a therapy in serum from 127 Asian patients with HBeAg-positive CHB. Sustained response was defined as hepatitis B e antigen (HBeAg) seroconversion 24 weeks post-treatment. RESULTS: Mean total HBs levels were significantly lower in responders versus nonresponders at all time points (P<.05) and decreased steadily during the initial 24 weeks' treatment (by 1.16 versus 0.86 ng/mL in responders/nonresponders, respectively) with unchanged relative proportions. Genotype B had a twofold higher proportion of LHBs than genotype C (13% versus 6%). HBV DNA, HBeAg, HBsAg, and HBs protein levels predicted response equally well but not optimally (area under the ROC curve values >0.70). CONCLUSIONS: HBs proteins levels differ by HBV genotype. However, quantification of HBs proteins has no advantage over the already established HBsAg assays to predict response to peginterferon alfa-2a therapy in HBeAg-positive patients.
    • Quorum-sensing antagonistic activities of azithromycin in Pseudomonas aeruginosa PAO1: a global approach.

      Nalca, Yusuf; Jänsch, Lothar; Bredenbruch, Florian; Geffers, Robert; Buer, Jan; Häussler, Susanne (2006-05-01)
      The administration of macrolides such as azithromycin for chronic pulmonary infection of cystic fibrosis patients has been reported to be of benefit. Although the mechanisms of action remain obscure, anti-inflammatory effects as well as interference of the macrolide with Pseudomonas aeruginosa virulence factor production have been suggested to contribute to an improved clinical outcome. In this study we used a systematic approach and analyzed the impact of azithromycin on the global transcriptional pattern and the protein expression profile of P. aeruginosa PAO1 cultures versus those in untreated controls. The most remarkable result of this study is the finding that azithromycin exhibited extensive quorum-sensing antagonistic activities. In accordance with the inhibition of the quorum-sensing systems, virulence factor production was diminished and the oxidative stress response was impaired, whereas the type III secretion system was strongly induced. Moreover, P. aeruginosa motility was reduced, which probably accounts for the previously observed impaired biofilm formation capabilities of azithromycin-treated cultures. The interference of azithromycin with quorum-sensing-dependent virulence factor production, biofilm formation, and oxidative stress resistance in P. aeruginosa holds great promise for macrolide therapy in cystic fibrosis. Clearly quorum-sensing antagonist macrolides should be paid more attention in the management of chronic P. aeruginosa infections, and as quorum-sensing antagonists, macrolides might gain vital importance for more general application against chronic infections.
    • [Reaction of microorganisms to the digestive fluid of the earthworms]

      Khomiakov, N V; Kharin, S A; Nechitaĭlo, T Iu; Golyshin, P N; Kurakov, A V; Byzov, B A; Zviagintsev, D G; Helmholtz Centre for Infection Research (formerly GBF) (2008-03-05)
      The reaction of soil bacteria and fungi to the digestive fluid of the earthworm Aporrectodea caliginosa was studied. The fluid was obtained by centrifugation of the native enzymes of the digestive tract. The inhibition of growth of certain bacteria, spores, and fungal hyphae under the effect of extracts from the anterior and middle sections of the digestive tract of A. caliginosa was discovered for the first time. In bacteria, microcolony formation was inhibited as early as 20-30 s after the application of the gut extracts, which may indicate the nonenzymatic nature of the effect. The digestive fluid exhibited the same microbicidal activity whether the earthworms were feeding on soil or sterile sand. This indicates that the microbicidal agents are formed within the earthworm's body, rather than by soil microorganisms. The effect of the digestive fluid from the anterior and middle divisions is selective in relation to different microorganisms. Of 42 strains of soil bacteria, seven were susceptible to the microbicidal action of the fluid (Alcaligenes.faecalis 345-1, Microbacterium sp. 423-1, Arthrobacter sp. 430-1, Bacillus megaterium 401-1, B. megaterium 413-1, Kluyvera ascorbata 301-1, Pseudomonas reactans 387-2). The remaining bacteria did not die in the digestive fluid. Of 13 micromycetes, the digestive fluid inhibited spore germination in Aspergillus terreus and Paecilomyces lilacinus and the growth of hyphae in Trichoderma harzianum and Penicillium decumbens. The digestive fluid stimulated spore germination in Alternaria alternata and the growth of hyphae in Penicillium chrysogenum. The reaction of the remaining micromycetes was neutral. The gut fluid from the posterior division of the abdominal tract did not possess microbicidal activity. No relation was found between the reaction of microorganisms to the effects of the digestive fluid and the taxonomic position of the microorganisms. The effects revealed are similar to those shown earlier for millipedes and wood lice in the following parameters: quick action of the digestive fluid on microorganisms, and the selectivity of the action on microorganisms revealed at the strain level. The selective effect of the digestive gut fluid of the earthworms on soil microorganisms is important for animal feeding, maintaining the homeostasis of the gut microbial community, and the formation of microbial communities in soils.
    • Recombinant protein production associated growth inhibition results mainly from transcription and not from translation.

      Li, Zhaopeng; Rinas, Ursula; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (BMC (part of Springer), 2020-04-06)
      Background: Recombinant protein production can be stressful to the host organism. The extent of stress is determined by the specific properties of the recombinant transcript and protein, by the rates of transcription and translation, and by the environmental conditions encountered during the production process. Results: The impact of the transcription of the T7-promoter controlled genes encoding human basic fibroblast growth factor (hFGF-2) and green fluorescent protein (GFP) as well as the translation into the recombinant protein on the growth properties of the production host E. coli BL21(DE3) were investigated. This was done by using expression vectors where the promoter region or the ribosome binding site(s) or both were removed. It is shown that already transcription without protein translation imposes a metabolic burden on the host cell. Translation of the transcript into large amounts of a properly folded protein does not show any effect on cell growth in the best case, e.g. high-level production of GFP in Luria-Bertani medium. However, translation appears to contribute to the metabolic burden if it is connected to protein folding associated problems, e.g. inclusion body formation. Conclusion: The so-called metabolic burden of recombinant protein production is mainly attributed to transcription but can be enhanced through translation and those processes following translation (e.g. protein folding and degradation, heat-shock responses).
    • Recombinant protein production-associated metabolic burden reflects anabolic constraints and reveals similarities to a carbon overfeeding response.

      Li, Zhaopeng; Rinas, Ursula; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Wiley, 2020-09-03)
      A comparison of the metabolic response of Escherichia coli BL21 (DE3) towards the production of human basic fibroblast growth factor (hFGF-2) or towards carbon overfeeding revealed similarities which point to constraints in anabolic pathways. Contrary to expectations, neither energy generation (e.g., ATP) nor provision of precursor molecules for nucleotides (e.g., uracil) and amino acids (e.g., pyruvate, glutamate) limit host cell and plasmid-encoded functions. Growth inhibition is assumed to occur when hampered anabolic capacities do not match with the ongoing and overwhelming carbon catabolism. Excessive carbon uptake leads to by-product secretion, for example, pyruvate, acetate, glutamate, and energy spillage, for example, accumulation and degradation of adenine nucleotides with concomitant accumulation of extracellular hypoxanthine. The cellular response towards compromised anabolic capacities involves downregulation of cAMP formation, presumably responsible for subsequently better-controlled glucose uptake and resultant accumulation of glucose in the culture medium. Growth inhibition is neglectable under conditions of reduced carbon availability when hampered anabolic capacities also match with catabolic carbon processing. The growth inhibitory effect with accompanying energy spillage, respectively, hypoxanthine secretion and cessation of cAMP formation is not unique to the production of hFGF-2 but observed during the production of other proteins and also during overexpression of genes without transcript translation.
    • Regulatory T Cells in an Endogenous Mouse Lymphoma Recognize Specific Antigen Peptides and Contribute to Immune Escape.

      Ahmetlić, Fatima; Riedel, Tanja; Hömberg, Nadine; Bauer, Vera; Trautwein, Nico; Geishauser, Albert; Sparwasser, Tim; Stevanović, Stefan; Röcken, Martin; Mocikat, Ralph; et al. (American Association for Cancer Research (AACR), 2019-03-20)
      Foxp3+ regulatory T cells (Tregs) sustain immune homeostasis and may contribute to immune escape in malignant disease. As a prerequisite for developing immunologic approaches in cancer therapy, it is necessary to understand the ontogeny and the antigenic specificities of tumor-infiltrating Tregs. We addressed this question by using a λ-MYC transgenic mouse model of endogenously arising B-cell lymphoma, which mirrors key features of human Burkitt lymphoma. We show that Foxp3+ Tregs suppress antitumor responses in endogenous lymphoma. Ablation of Foxp3+ Tregs significantly delayed tumor development. The ratio of Treg to effector T cells was elevated in growing tumors, which could be ascribed to differential proliferation. The Tregs detected were mainly natural Tregs that apparently recognized self-antigens. We identified MHC class II-restricted nonmutated self-epitopes, which were more prevalent in lymphoma than in normal B cells and could be recognized by Tregs. These epitopes were derived from proteins that are associated with cellular processes related to malignancy and may be overexpressed in the tumor.
    • Relevance of inducible nitric oxide synthase for immune control of Mycobacterium avium subspecies paratuberculosis infection in mice.

      Abdissa, Ketema; Ruangkiattikul, Nanthapon; Ahrend, Wiebke; Nerlich, Andreas; Beineke, Andreas; Laarmann, Kristin; Janze, Nina; Lobermeyer, Ulrike; Suwandi, Abdulhadi; Falk, Christine; et al. (Taylor & Francis, 2020-05-14)
      Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne's disease (JD), an incurable chronic intestinal bowel disease in ruminants. JD occurs worldwide and causes enormous economic burden in dairy industry. Research on JD pathobiology is hampered by its complexity which cannot completely be mimicked by small animal models. As a model the mouse allows dissecting some pathogenicity features of MAP. However, for unknown reasons MAP exhibits reduced growth in granulomas of infected mice compared to other Mycobacterium avium subspecies. Here, we characterized immune reactions of MAP-infected C57BL/6 mice. After infection, mice appeared fully immunocompetent. A strong antigen-specific T cell response was elicited indicated by IFNγ production of splenic T cells re-stimulated with MAP antigens. Function of splenic dendritic cells and proliferation of adoptively transferred antigen-specific CD4+ T cells was unaltered. Isolated splenic myeloid cells from infected mice revealed that MAP resides in CD11b+ macrophages. Importantly, sorted CD11b+CD11c- cells expressed high level of type 2 nitric oxide synthase (NOS2) but only low levels of pro- and anti-inflammatory cytokines. Correspondingly, MAP-infected MAC2 expressing myeloid cells in spleen and liver granuloma displayed strong expression of NOS2. In livers of infected Nos2-/-mice higher bacterial loads, more granuloma and larger areas of tissue damage were observed 5 weeks post infection compared to wild type mice. In vitro, MAP was sensitive to NO released by a NO-donor. Thus, a strong T cell response and concomitant NOS2/NO activity appears to control MAP infection, but allows development of chronicity and pathogen persistence. A similar mechanism might explain persistence of MAP in ruminants.
    • RNase Y-mediated regulation of the streptococcal pyrogenic exotoxin B.

      Broglia, Laura; Materne, Solange; Lécrivain, Anne-Laure; Hahnke, Karin; Le Rhun, Anaïs; Charpentier, Emmanuelle; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (2018-01-01)
      Endoribonuclease Y (RNase Y) is a crucial regulator of virulence in Gram-positive bacteria. In the human pathogen Streptococcus pyogenes, RNase Y is required for the expression of the major secreted virulence factor streptococcal pyrogenic exotoxin B (SpeB), but the mechanism involved in this regulation remains elusive. Here, we demonstrate that the 5' untranslated region of speB mRNA is processed by several RNases including RNase Y. In particular, we identify two RNase Y cleavage sites located downstream of a guanosine (G) residue. To assess whether this nucleotide is required for RNase Y activity in vivo, we mutated it and demonstrate that the presence of this G residue is essential for the processing of the speB mRNA 5' UTR by RNase Y. Although RNase Y directly targets and processes speB, we show that RNase Y-mediated regulation of speB expression occurs primarily at the transcriptional level and independently of the processing in the speB mRNA 5' UTR. To conclude, we demonstrate for the first time that RNase Y processing of an mRNA target requires the presence of a G. We also provide new insights on the speB 5' UTR and on the role of RNase Y in speB regulation.
    • The role of epigenetics in the development of childhood asthma.

      Qi, Cancan; Xu, Cheng-Jian; Koppelman, Gerard H; TWINCORE, Zentrum für experimentelle und klinische Infektionsforschung GmbH,Feodor-Lynen Str. 7, 30625 Hannover, Germany. (2019-11-10)
      Introduction: The development of childhood asthma is caused by a combination of genetic factors and environmental exposures. Epigenetics describes mechanisms of (heritable) regulation of gene expression that occur without changes in DNA sequence. Epigenetics is strongly related to aging, is cell-type specific, and includes DNA methylation, noncoding RNAs, and histone modifications.Areas covered: This review summarizes recent epigenetic studies of childhood asthma in humans, which mostly involve studies of DNA methylation published in the recent five years. Environmental exposures, in particular cigarette smoking, have significant impact on epigenetic changes, but few of these epigenetic signals are also associated with asthma. Several asthma-associated genetic variants relate to DNA methylation. Epigenetic signals can be better understood by studying their correlation with gene expression, which revealed higher presence and activation of blood eosinophils in asthma. Strong associations of nasal methylation signatures and atopic asthma were identified, which were replicable across different populations.Expert commentary: Epigenetic markers have been strongly associated with asthma, and might serve as biomarker of asthma. The causal and longitudinal relationships between epigenetics and disease, and between environmental exposures and epigenetic changes need to be further investigated. Efforts should be made to understand cell-type-specific epigenetic mechanisms in asthma.
    • RovC - a novel type of hexameric transcriptional activator promoting type VI secretion gene expression.

      Knittel, Vanessa; Sadana, Pooja; Seekircher, Stephanie; Stolle, Anne-Sophie; Körner, Britta; Volk, Marcel; Jeffries, Cy M; Svergun, Dmitri I; Heroven, Ann Kathrin; Scrima, Andrea; et al. (PLOS, 2020-09-23)
      Type VI secretion systems (T6SSs) are complex macromolecular injection machines which are widespread in Gram-negative bacteria. They are involved in host-cell interactions and pathogenesis, required to eliminate competing bacteria, or are important for the adaptation to environmental stress conditions. Here we identified regulatory elements controlling the T6SS4 of Yersinia pseudotuberculosis and found a novel type of hexameric transcription factor, RovC. RovC directly interacts with the T6SS4 promoter region and activates T6SS4 transcription alone or in cooperation with the LysR-type regulator RovM. A higher complexity of regulation was achieved by the nutrient-responsive global regulator CsrA, which controls rovC expression on the transcriptional and post-transcriptional level. In summary, our work unveils a central mechanism in which RovC, a novel key activator, orchestrates the expression of the T6SS weapons together with a global regulator to deploy the system in response to the availability of nutrients in the species' native environment.
    • Selective Host Cell Death by Staphylococcus aureus : A Strategy for Bacterial Persistence.

      Missiakas, Dominique; Winstel, Volker; TWINCORE, Zentrum für experimentelle und klinische Infektionsforschung GmbH,Feodor-Lynen Str. 7, 30625 Hannover, Germany. (Frontiers, 2021-01-21)
      Host cell death programs are fundamental processes that shape cellular homeostasis, embryonic development, and tissue regeneration. Death signaling and downstream host cell responses are not only critical to guide mammalian development, they often act as terminal responses to invading pathogens. Here, we briefly review and contrast how invading pathogens and specifically Staphylococcus aureus manipulate apoptotic, necroptotic, and pyroptotic cell death modes to establish infection. Rather than invading host cells, S. aureus subverts these cells to produce diffusible molecules that cause death of neighboring hematopoietic cells and thus shapes an immune environment conducive to persistence. The exploitation of cell death pathways by S. aureus is yet another virulence strategy that must be juxtaposed to mechanisms of immune evasion, autophagy escape, and tolerance to intracellular killing, and brings us closer to the true portrait of this pathogen for the design of effective therapeutics and intervention strategies.
    • shift from acetoclastic to H2-dependent methanogenesis in a west Siberian peat bog at low pH values and isolation of an acidophilic Methanobacterium strain.

      Kotsyurbenko, O R; Friedrich, M W; Simankova, M V; Nozhevnikova, A N; Golyshin, P N; Timmis, K N; Conrad, R; Institut für Mikrobiologie, Carolo-Wilhelmina Technische Universität zu Braunschweig, Biozentrum, Braunschweig, Germany. olk@helmholtz-hzi.de (2007-04)
      Methane production and archaeal community composition were studied in samples from an acidic peat bog incubated at different temperatures and pH values. H(2)-dependent methanogenesis increased strongly at the lowest pH, 3.8, and Methanobacteriaceae became important except for Methanomicrobiaceae and Methanosarcinaceae. An acidophilic and psychrotolerant Methanobacterium sp. was isolated using H(2)-plus-CO(2)-supplemented medium at pH 4.5.
    • Sialylation Is Dispensable for Early Murine Embryonic Development in Vitro.

      Abeln, Markus; Borst, Kristina M; Cajic, Samanta; Thiesler, Hauke; Kats, Elina; Albers, Iris; Kuhn, Maike; Kaever, Volkhard; Rapp, Erdmann; Münster-Kühnel, Anja; et al. (2017-07-04)
      The negatively charged nonulose sialic acid (Sia) is essential for murine development in vivo. In order to elucidate the impact of sialylation on differentiation processes in the absence of maternal influences, we generated mouse embryonic stem cell (mESC) lines that lack CMP-Sia synthetase (CMAS) and thereby the ability to activate Sia to CMP-Sia. Loss of CMAS activity resulted in an asialo cell surface accompanied by an increase in glycoconjugates with terminal galactosyl and oligo-LacNAc residues, as well as intracellular accumulation of free Sia. Remarkably, these changes did not impact intracellular metabolites or the morphology and transcriptome of pluripotent mESC lines. Moreover, the capacity of Cmas
    • Simple and rapid 5' and 3' extension techniques in RT-PCR.

      Struck, F; Collins, J (1994-05-25)
    • Solubility and Stability Enhanced Oral Formulations for the Anti-Infective Corallopyronin A.

      Krome, Anna K; Becker, Tim; Kehraus, Stefan; Schiefer, Andrea; Steinebach, Christian; Aden, Tilman; Frohberger, Stefan J; López Mármol, Álvaro; Kapote, Dnyaneshwar; Jansen, Rolf; et al. (MDPI, 2020-11-18)
      Novel-antibiotics are urgently needed to combat an increase in morbidity and mortality due to resistant bacteria. The preclinical candidate corallopyronin A (CorA) is a potent antibiotic against Gram-positive and some Gram-negative pathogens for which a solid oral formulation was needed for further preclinical testing of the active pharmaceutical ingredient (API). The neat API CorA is poorly water-soluble and instable at room temperature, both crucial characteristics to be addressed and overcome for use as an oral antibiotic. Therefore, amorphous solid dispersion (ASD) was chosen as formulation principle. The formulations were prepared by spray-drying, comprising the water-soluble polymers povidone and copovidone. Stability (high-performance liquid chromatography, Fourier-transform-infrared spectroscopy, differential scanning calorimetry), dissolution (biphasic dissolution), and solubility (biphasic dissolution, Pion's T3 apparatus) properties were analyzed. Pharmacokinetic evaluations after intravenous and oral administration were conducted in BALB/c mice. The results demonstrated that the ASD formulation principle is a suitable stability- and solubility-enhancing oral formulation strategy for the API CorA to be used in preclinical and clinical trials and as a potential market product.
    • Soluble immune markers in the different phases of chronic hepatitis B virus infection

      Wiegand, Steffen B.; Beggel, Bastian; Wranke, Anika; Aliabadi, Elmira; Jaroszewicz, Jerzy; Xu, Cheng Jian; Li, Yang; Manns, Michael P.; Lengauer, Thomas; Wedemeyer, Heiner; et al. (Nature publishing group, 2019-10-01)
      Chronic hepatitis B virus (HBV) infection may follow four different consecutive phases, which are defined by virology as well as biochemical markers and differ in terms of prognosis and need for antiviral treatment. Currently, host responses reflected by immune markers are not considered in this definition. We aimed to study soluble immune markers and their distribution in different phases of chronic HBV infection. In this cross-sectional retrospective study, we investigated a panel of 14 soluble immune markers (SIM) including CXCL10 in 333 patients with chronic HBV infection. In a small cohort of HBeAg positive patients we analyzed SIM before and after HBeAg seroconversion and compared seroconverters to patients with unknown outcome. Significant differences were documented in the levels of several SIM between the four phases of chronic HBV infection. The most pronounced difference among all investigated SIM was observed for CXCL10 concentrations with highest levels in patients with hepatitis. TGF-β and IL-17 revealed different levels between HBeAg negative patients. HBeAg positive patients with HBeAg seroconversion presented higher amounts of IL-12 before seroconversion compared to HBeAg positive patients with unknown follow up. SIM such as CXCL10 but also IL-12, TGF-β and IL-17 may be useful markers to further characterize the phase of chronic HBV infection.
    • Sonderforschungsbereich SFB 738: Optimierung konventioneller und innovativer Transplantate

      Manns, Michael P; Huber, Petra; Jaeckel, Elmar; Helmholtz Zentrum für Infektionsforschung GmbH, Inhoofenstr. 7, 38124 Braunschweig, Germany. (2017-08-09)