Peter Schmidtke

Johannes Gutenberg-Universität Mainz, Mayence, Rheinland-Pfalz, Germany

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Publications (13)40.25 Total impact

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    ABSTRACT: We have reported that cordycepin, an adenosine derivative from the fungus Cordyceps, increased interleukin (IL)-10 expression, decreased IL-2 expression and suppressed T lymphocyte activity. In the present study, we further characterized the regulatory effects of cordycepin on human immune cells. Moreover, a traditional Chinese drug, Cordyceps sinensis (CS) that contains cordycepin, was also investigated. Cytometric Bead Array (CBA) was used to determine the concentrations of IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, TNF-alpha and IFN-gamma in culture of peripheral blood mononuclear cells (PBMCs). The results showed that both cordycepin and CS up-regulated IL-10, IL-1beta, IL-6, IL-8 and TNF-alpha; at the same time, they suppressed phytohemagglutinin (PHA)-induced production of IL-2, IL-4, IL-5, IFN-gamma and IL-12. As compared to cordycepin, CS displayed its regulatory effects on IL-2 and IL-10 in a similar dose-dependent manner even with higher efficiency. The binding activity of transcription factors in a human monocytic cell line THP-1 was tested by the trans-AM method, and a higher binding activity of SP1 and SP3 was observed in cordycepin or CS treated cells compared to the control. These results led to the opinion that cordycepin and CS pleiotropically affected the actions of immune cells and cytokine network in a similar fashion. Cordycepin could be an important immunoregulatory active ingredient in Cordyceps sinensis. In addition, CS may contain substances which possess synergism with cordycepin, as CS showed a higher efficiency in the production of IL-10 and IL-2 than cordycepin. However, merits of these effects in pharmacology and clinical medicine have yet to be proven and the precise mechanism of these immune regulatory actions should be researched.
    No preview · Article · Feb 2008 · The American Journal of Chinese Medicine
  • Xiaoxia Zhou · Peter Schmidtke · Fred Zepp · Claudius U Meyer
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    ABSTRACT: More than forty cytokines have been extensively researched on the molecular structure, cell signaling and transduction pathway. With respect to cytokine-regulating therapy in immunological imbalance however, the reported results are conflicting because of the pleiotropic functions and the intricate interactions of the cytokine network. In this review, we outline the observations on interleukin-10 (IL-10) upregulatory therapy. Despite varying opinions on its therapeutic effects for different disorders, IL-10 has been considered a potential anti-inflammatory cytokine. Numerous studies support the view that IL-10 shows a strong suppressive effect on Th1 lymphocytes, antigen presenting cells and the production of inflammatory mediators. It is also noticeable that recent research has revealed the relationship between IL-10 induced antigen specific regulatory CD4+ T cells and antigen specific immune tolerance. This specific regulation was mediated in part through IL-10 secretion, because anti-IL-10 treatment reverted the inhibitory effect of regulatory T cell clones. In different models, these cells were shown to inhibit both Th1 and Th2-type inflammatory responses through the secretion of IL-10. With the presence of IL-10, regulatory T cells may induce peripheral immune tolerance. Exogenous administration, transgenic expression and endogenous stimulative agents of IL-10 have been used for a variety of inflammatory diseases, autoimmune diseases and allograft rejection in patients and experimental models. A therapeutic intervention with drug inducing endogenous IL-10 may be more practical than an exogenous administration of IL-10 with transient effect. Although further investigation on gene regulation of IL-10 is necessary, increasing studies have been reported concerning the attempt to develop the agents, which could promote endogenous IL-10 production for the treatment of immunological disorders and inflammatory diseases. With some unclear mechanisms, these agents have strongly upregulated IL-10 production in vitro or in vivo. Reported IL-10 upregulatory agents have shown promising prospects for remission of autoimmune diseases and inflammatory diseases and have even induced antigen specific immune tolerance. It is interesting that the IL-10 upregulatory effect of several traditional immunosuppressive drugs has been detected, e.g. glucocorticoid, which is considered "not more as an immunosuppressive drug but an immune modulating agent". Approximately twenty IL-10 upregulatory agents as instances are described in the present review. In addition, their therapeutic effects in various diseases are discussed.
    No preview · Article · Jan 2006 · Current Drug Targets - Immune Endocrine & Metabolic Disorders
  • P Schmidtke · P Habermehl · M Knuf · C.U. Meyer · R Sänger · F Zepp
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    ABSTRACT: The humoral and cellular immune response to inactivated hepatitis A vaccine was investigated dynamically in a time elapse study over 1 year. Fourty-five healthy volunteers, seronegative for anti-HAV, were vaccinated with 1440 enzyme-linked immunosorbent assay units (EU) of formalin-inactivated hepatitis A virus following a 0--6-month schedule. Serum anti-HAV levels and HAV-specific proliferation of peripheral blood mononuclear cells were measured at several time points over a 26- and 28-week period after the first and second injection, respectively. Distinct B and T cell responses were determined within 14 days after primary vaccination. The booster vaccination-induced immediate peak levels for the humoral (anti-HAV GMC=5376mIU/ml) as well as the cellular (median Deltacpm=14173cpm) response.
    No preview · Article · Nov 2005 · Vaccine
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    ABSTRACT: Specific functional properties of dendritic cells (DCs) have been suspected as being responsible for the impaired specific immune responses observed in human neonates. To analyze stimulatory requirements for the critical transition from immature, antigen-processing DCs to mature, antigen-presenting DCs, we investigated the effect of different proinflammatory mediators and antigens on phenotype and cytokine secretion of human neonatal DCs derived from hematopoietic progenitor cells (HPCs). Whereas single proinflammatory mediators were unable to induce the maturation of neonatal DCs, various combinations of IFNgamma, CD40L, TNFalpha, LPS and antigens, induced the maturation of neonatal DCs documented by up-regulation of HLA-DR, CD83 and CD86. Combinations of proinflammatory mediators also increased cytokine secretion by neonatal DCs. Especially combined stimulation with LPS and IFNgamma proved to be very efficient in inducing maturation and cytokine synthesis of neonatal DCs. In conclusion, neonatal DCs can be stimulated to express maturation as well as costimulatory surface molecules. However, induction of maturation requires combined stimulation with multiple proinflammatory signals.
    Full-text · Article · Jul 2005 · Clinical and Developmental Immunology
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    ABSTRACT: We have analyzed several cases of Beckwith-Wiedemann syndrome (BWS) with Wilms' tumor in a familial setting, which give insight into the complex controls of imprinting and gene expression in the chromosome 11p15 region. We describe a 2.2-kbp microdeletion in the H19/insulin-like growth factor 2 (IGF2)-imprinting center eliminating three target sites of the chromatin insulator protein CTCF that we believe here is necessary, but not sufficient, to cause BWS and Wilms' tumor. Maternal inheritance of the deletion is associated with IGF2 loss of imprinting and up-regulation of IGF2 mRNA. However, in at least one affected family member a second genetic lesion (a duplication of maternal 11p15) was identified and accompanied by a further increase in IGF2 mRNA levels 35-fold higher than control values. Our results suggest that the combined effects of the H19/IGF2-imprinting center microdeletion and 11p15 chromosome duplication were necessary for manifestation of BWS.
    Full-text · Article · Apr 2005 · Proceedings of the National Academy of Sciences
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    ABSTRACT: The receptor tyrosine kinase ERBB2 plays a central role in the development of breast cancer and other epithelial malignancies. Elevated ERBB2 activity is believed to transform cells by transmitting mitogenic and antiapoptotic signals. Here we show that tightly regulated overexpression of oncogenic ERBB2 in human breast carcinoma cells does not stimulate proliferation but provokes premature senescence, accompanied by up-regulation of the cyclin-dependent kinase inhibitor P21(WAF1/CIP1). A similar effect was caused by retrovirus-mediated overexpression of oncogenic ERBB2 in low-passage murine embryonic fibroblasts. In contrast to previous observations based on constitutively overexpressing cell lines, P21 induced by tetracycline-regulated ERBB2 localizes to the nucleus in arrested cells. P21 up-regulation seems to be independent of the P53 tumor suppressor protein, and senescence-associated phenotypic alterations are reversed by specific inhibition of P38 mitogen-activated protein kinases. Functional inactivation of P21 by antisense oligonucleotides is sufficient to prevent cell cycle arrest as well as the senescent phenotype, thereby identifying the P21 protein as the key mediator of hypermitogenic cell cycle arrest and premature senescence in breast carcinoma cells. Our results may thus indicate that premature senescence represents an inherent anticarcinogenic program during ERBB2-driven mammary tumorigenesis. We propose a multistep model for the process of malignant transformation by ERBB2 wherein secondary lesions either target P21 or downstream effectors of senescence to bypass this primary fail-safe mechanism.
    Full-text · Article · Mar 2005 · Cancer Research

  • No preview · Article · Jan 2003 · Klinische Pädiatrie
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    Xiaoxia Zhou · Claudius U Meyer · Peter Schmidtke · Fred Zepp
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    ABSTRACT: Therapeutic options for controlling autoimmune diseases are still very limited. Interleukin-10 has been reported to be a promising approach to therapeutic intervention. In the search for a drug which results in the selective upregulation of interleukin-10, we investigated the immunoregulative effects of cordycepin. We have measured interleukin-10 and interleukin-2 secretion of human peripheral blood mononuclear cells that were incubated with cordycepin and assessed the influence of cordycepin on the expression of interleukin-10 mRNA, the proliferative response and the expression of surface markers on T lymphocytes. In addition, the subsets of interleukin-10-secreting cells, the influence of anti-interleukin-10 neutralizing antibody and cytotoxicity of cordycepin were evaluated. Our results suggest that cordycepin has a significantly upregulative effect on interleukin-10 production and interleukin-10 mRNA expression. Interleukin-10-producing cells included in CD4+, CD8+, CD19+, CD56+ and CD14+ cells. At the same time, cordycepin inhibited phytohaemagglutinin-induced interleukin-2 production and proliferation of peripheral blood mononuclear cells. A restricted T lymphocyte activation was also reflected by a reduced expression of the surface markers CD25, CD45RO, CD54, CD71 and HLA DR. Anti-interleukin-10 neutralizing antibody could not completely block the suppressive effect of cordycepin on production of interleukin-2. Cordycepin in the effective concentration presented slight cytotoxicity but did not increase apoptosis. These results indicate that cordycepin exerts immunoregulative effects. Further research on it may provide an approach for the development of novel immunomodulatory drugs which directly alter the secretion of cytokines.
    Full-text · Article · Nov 2002 · European Journal of Pharmacology

  • No preview · Article · Sep 1998 · Geburtshilfe und Frauenheilkunde
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    ABSTRACT: To evaluate the reactogenicity and immunogenicity of a Haemophilus influenzae type b conjugate vaccine (HbOC) and of a tricomponent acellular pertussis vaccine (DTaP) when injected simultaneously into either contralateral arms or into contralateral thighs, 110 infants were enrolled to receive three doses of DTaP at 3, 4, and 5 months and two HbOC doses at 3 and 5 months of age. Administration of either of the two vaccines into arms was associated with significantly more local side effects than administration into thighs. There was no difference in geometric mean concentration (GMC) values for any of the four vaccine antigens between subjects who had been vaccinated into arms or thighs. After immunization, all children had protective antibody titers to diphtheria toxin. While post vaccination the mean anti-tetanus toxoid GMC was > or = 1.25 IU/ml, there was no significant rise as compared to the GMC before vaccination. GMCs of antibodies against the various pertussis antigens were similar to those observed before with the same DTaP vaccine. The simultaneous administration of DTaP and HbOC was safe and immunogenic irrespective of the site of vaccine administration, but significantly more local reactions occurred when vaccines were injected into arms.
    No preview · Article · Sep 1997 · Infection
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    ABSTRACT: Background: DTaP vaccines are the basis for future multivalent combination vaccines. However, administering DTaP and Haemophilus influenzae type b (Hib) vaccines as a mixed injection was found to reduce Hib-specific antibodies without interfering with immunologie priming. It is unknown if coadministration influences CMI-responses to other vaccine antigens. Here we investigated the impact of the mixed DTaP/Hib vaccine on pertussis-specific CMI-responses in infants. Materials and Methods: 500 healthy children were primed with DTaP and Hib-tetanus conjugated vaccines (SB-Bio) at the age of 3, 4 and 5 month. Booster doses of DTaP and Hib were given at 15-22 months. 48 individuals (DTaP/Hib same limb: 24, DTaP/Hib in different limbs: 24) were randomly chosen for in vitro analysis of pertussis-specific CMI-response. Blood was drawn pre and post (30 d) booster and the proliferative response of T lymphocytes was assayed after 5.5 d cultivation in the presence of pertussis antigens by 3H-TdR incorporation. Cytokines (11-5, IFNγ) secreted from antigen-challenged lymphocytes were detected by ELISA-technique. Results: For all three pertussis-antigens a significant proliferative response compared to a control without antigen was documented. Vaccinees who received DTaP and Hib mixed in a single injection had pre and post values comparable to those receiving vaccines in different limbs. Differentiation of TH1/Th2-responses by antigen-stimulated T cells showed a tendency towards a Th1-type response. Thl/TH2-differentiation was not influenced by modes of administration as indicated by comparable amounts of IFNy and IL-5. Conclusions: Our data show that the cellular immune response for pertussis is prominent and not influenced by the mixed administration of DTaP and Hib vaccines. This is in accordance with the recent findings that the antibodies to the pertussis antigens are not influenced by mixed injection.
    No preview · Article · Jan 1997
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    F Zepp · M Knuf · P Habermehl · J H Schmitt · C Rebsch · P Schmidtke · R Clemens · M Slaoui
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    ABSTRACT: The aim of this study was to investigate pertussis-specific cell-mediated immunity in infants vaccinated with a tricomponent acellular vaccine. Infants were investigated during a primary vaccination schedule from the third month of life to the sixth month as well as before and after a booster at 15 to 24 months. This is the first report of specific cell-mediated immune responses to pertussis-related antigens in infants below the age of 12 months. Our data show that the vaccine induces T-cell responses specific for the vaccine components, detoxified pertussis toxin, filamentous hemagglutinin, and pertactin, that increase progressively over the course of the vaccination schedule. In contrast to declining antibody titers, cell-mediated immune responses are stable over the postprimary to prebooster period. Vaccination results in a progressive increase in the number of T cells that express activation marker CD45RO preferentially on CD4-positive T cells after stimulation with pertussis antigens. Measurements of cytokine secretion profiles demonstrated a preferential induction of interleukin 2- and gamma interferon-producing T-helper 1 cells and only low production of interleukin 10. The observed persistence of the specific cell-mediated immunity may have a bearing on the protective mechanisms induced by pertussis vaccination. Cell-mediated immunity requires further study, particularly to improve our understanding of the persistence of protection afforded by vaccination up to the administration of booster doses.
    Full-text · Article · Nov 1996 · Infection and Immunity
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    ABSTRACT: Lymphadenitis colli due to NTM should always be considered in children with cervical Lymphadenitis. For Germany there is a lack of data concerning the incidence, the epidemiology, the diversity and frequency of the different bacteria, the diagnosis, the clinical manifestation and the medical treatment. By means of a questionnaire, which was retrospective for 1985 to 1994 and was sent to 277 children's hospitals in Germany, we collected data on Lymphadenitis colli in Germany. In our study we also incorporated cases from the "National Laboratory for Mycobacteria" in Borstel as well as six cases from our hospital in Mainz. Therefore our data includes both clinical (28) and laboratory (30) cases. Additionally we screened the literature on "Lymphadenitis colli in children due to NTM". A total of 51 cases of Lymphadenitis due to NTM could be identified. The illness occurs typically in young children up to six years of age. The most frequent cause were species of the Mycobacterium avium-intracellulare-scrofulaceum complex. Except for the local diagnosis of a cervical Lymphadenitis other clinical symptoms are missing, just as specific laboratory parameters with a subacute or chronic course. The tuberculin skin test can be false positive. The diagnosis is confirmed by biopsy and histology as well as through microbiological tests. The best treatment is complete surgical excision, whereas the importance of additional or exclusive treatment with Clarithromycin, Rifabutin and other antibiotics could not be clarified completely. But in patients with AIDS Rifabutin and other drugs could perhaps be useful, even for prophylaxis. Also if complete excision is impossible, treatment with certain drugs (Clarithromycin or Azithromycin in combination with Rifampicin) will be recommended. It still remains in question if NTM infections in children are really increasing.
    No preview · Article · · Klinische Pädiatrie