Dittmann, Kai

[["dc.bibliographiccitation.firstpage","1398"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Molecular and Cellular Biology"],["dc.bibliographiccitation.lastpage","1411"],["dc.bibliographiccitation.volume","34"],["dc.contributor.author","Schneppenheim, Janna"],["dc.contributor.author","Huettl, Susann"],["dc.contributor.author","Mentrup, Torben"],["dc.contributor.author","Luellmann-Rauch, Renate"],["dc.contributor.author","Rothaug, Michelle"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Araki, Masatake"],["dc.contributor.author","Araki, Kimi"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Fluhrer, Regina"],["dc.contributor.author","Saftig, Paul"],["dc.contributor.author","Schroeder, Bernd"],["dc.date.accessioned","2018-11-07T09:42:09Z"],["dc.date.available","2018-11-07T09:42:09Z"],["dc.date.issued","2014"],["dc.description.abstract","We reported recently that the presenilin homologue signal peptide peptidase-like 2a (SPPL2a) is essential for B cell development by cleaving the N-terminal fragment (NTF) of the invariant chain (li, CD74). Based on this, we suggested that pharmacological modulation of SPPL2a may represent a novel approach to deplete B cells in autoimmune disorders. With regard to reported overlapping substrate spectra of SPPL2a and its close homologue, SPPL2b, we investigated the role of SPPL2b in CD74 NTF proteolysis and its impact on B and dendritic cell homeostasis. In heterologous expression experiments, SPPL2b was found to cleave CD74 NTF with an efficiency simliar to that of SPPL2a. For in vivo analysis, SPPL2b single-deficient and SPPL2a/SPPL2b double-deficient mice were generated and examined for CD74 NTF turnover/accumulation, B cell maturation and functionality, and dendritic cell homeostasis. We demonstrate that in vivo SPPL2b does not exhibit a physiologically relevant contribution to CD74 proteolysis in B and dendritic cells. Furthermore, we reveal that both proteases exhibit divergent subcellular localizations in B cells and different expression profiles in murine tissues. These findings suggest distinct functions of SPPL2a and SPPL2b and, based on a high abundance of SPPL2b in brain, a physiological role of this protease in the central nervous system."],["dc.identifier.doi","10.1128/MCB.00038-14"],["dc.identifier.isi","000333338600003"],["dc.identifier.pmid","24492962"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33889"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Soc Microbiology"],["dc.relation.issn","1098-5549"],["dc.relation.issn","0270-7306"],["dc.title","The Intramembrane Proteases Signal Peptide Peptidase-Like 2a and 2b Have Distinct Functions In Vivo"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1587"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Cancer Immunology Immunotherapy"],["dc.bibliographiccitation.lastpage","1597"],["dc.bibliographiccitation.volume","62"],["dc.contributor.author","Koenig, Simone"],["dc.contributor.author","Regen, Tommy"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Schwendener, Reto"],["dc.contributor.author","Hanisch, Uwe-Karsten"],["dc.contributor.author","Pukrop, Tobias"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T09:19:32Z"],["dc.date.available","2018-11-07T09:19:32Z"],["dc.date.issued","2013"],["dc.description.abstract","Liposomes are frequently used in cancer therapy to encapsulate and apply anticancer drugs. Here, we show that a systemic treatment of mice bearing skin tumors with empty phosphatidylcholine liposomes (PCL) resulted in inhibition of tumor growth, which was similar to that observed with the synthetic bacterial lipoprotein and TLR1/2 agonist Pam(3)CSK(4) (BLP). Both compounds led to a substantial decrease of macrophages in spleen and in the tumor-bearing skin. Furthermore, both treatments induced the expression of typical macrophage markers in the tumor-bearing tissue. As expected, BLP induced the expression of the M1 marker genes Cxcl10 and iNOS, whereas PCL, besides inducing iNOS, also increased the M2 marker genes Arg1 and Trem2. In vitro experiments demonstrated that neither PCL nor BLP influenced proliferation or survival of tumor cells, whereas both compounds inhibited proliferation and survival and increased the migratory capacity of bone marrow-derived macrophages (BMDM). However, in contrast to BLP, PCL did not activate cytokine secretion and induced a different BMDM phenotype. Together, the data suggest that similar to BLP, PCL induce an antitumor response by influencing the tumor microenvironment, in particular by functional alterations of macrophages, however, in a distinct manner from those induced by BLP."],["dc.description.sponsorship","DFG [FOR942 HA 2197/5-2]"],["dc.identifier.doi","10.1007/s00262-013-1444-4"],["dc.identifier.isi","000325008800005"],["dc.identifier.pmid","23917775"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28662"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0340-7004"],["dc.title","Empty liposomes induce antitumoral effects associated with macrophage responses distinct from those of the TLR1/2 agonist Pam(3)CSK(4) (BLP)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5354"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","The journal of immunology"],["dc.bibliographiccitation.lastpage","5358"],["dc.bibliographiccitation.volume","191"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Oellerich, Thomas"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Hsiao, He-Hsuan"],["dc.contributor.author","Urlaub, Henning"],["dc.contributor.author","Serve, Hubert"],["dc.contributor.author","Griesinger, Christian"],["dc.contributor.author","Wienands, Jürgen"],["dc.date.accessioned","2017-09-07T11:47:02Z"],["dc.date.available","2017-09-07T11:47:02Z"],["dc.date.issued","2013"],["dc.description.abstract","Ag-mediated B cell stimulation relies on phospholipase C gamma 2 (PLC gamma 2) for Ca2+ mobilization. Enzymatic activity of PLC gamma 2 is triggered upon Src homology 2 domain-mediated binding to the tyrosine-phosphorylated adaptor SLP65. However, SLP65 phosphorylation outlasts the elevation of cytosolic Ca2+ concentration suggesting additional levels of PLC gamma 2 regulation. We show in this article that the functionality of the PLC gamma 2/SLP65 complex is controlled by the weakly characterized C2 domain of PLC gamma 2. Usually C2 domains bind membrane lipids, but that of PLC gamma 2 docks in a Ca2+-regulated manner to a distinct phosphotyrosine of SLP65. Hence, early Ca2+ fluxing provides feed-forward signal amplification by promoting anchoring of the PLC gamma 2 C2 domain to phospho-SLP65. As the cellular Ca2+ resources become exhausted, the concomitant decline of Ca2+ dampens the C2-phosphotyrosine interaction so that PLC gamma 2 activation terminates despite sustained SLP65 phosphorylation."],["dc.identifier.doi","10.4049/jimmunol.1301326"],["dc.identifier.gro","3142245"],["dc.identifier.isi","000327180600005"],["dc.identifier.pmid","24166973"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/6143"],["dc.notes.intern","WoS Import 2017-03-10 / Funder: Deutsche Forschungsgemeinschaft [SFB 860, B5]"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Amer Assoc Immunologists"],["dc.relation.eissn","1550-6606"],["dc.relation.issn","0022-1767"],["dc.title","Cutting Edge: Feed-Forward Activation of Phospholipase C gamma 2 via C2 Domain-Mediated Binding to SLP65"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","235"],["dc.bibliographiccitation.journal","Immunological Reviews"],["dc.bibliographiccitation.lastpage","246"],["dc.bibliographiccitation.volume","218"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Engels, Niklas"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Stork, Bjorn"],["dc.contributor.author","Wienands, Juergen"],["dc.date.accessioned","2018-11-07T11:00:05Z"],["dc.date.available","2018-11-07T11:00:05Z"],["dc.date.issued","2007"],["dc.description.abstract","B cells respond to antigen stimulation with mobilization of the Ca2+ second messenger in two phases operated by two distinct sets of effector proteins. First, an antigen receptor-specific Ca2+ initiation complex is assembled, activated, and targeted to the plasma membrane to trigger the transient release of Ca2+ from intracellular stores of the endoplasmic reticulum. Second, more ubiquitously expressed Ca2+ channels of the plasma membrane are opened to allow for sustained Ca2+ influx from the extracellular medium. Depending on the developmental stage of the B cell, the kinetics and profile of the two phases are adjusted at multiple levels of positive and negative regulation. A molecular basis for the Ca2+ signaling plasticity is provided by cytosolic and transmembrane adapter proteins. They act as signal organizers, which control enzyme/substrate interactions by directing the different signaling modules into specific subcellular compartments. These arrangements orchestrate a graduated activation of Ca2+-sensitive downstream pathways, which ultimately determine appropriate cellular responses, namely elimination of autoreactive B cells or proliferation and differentiation of immunocompetent B cells into antibody-secreting plasma cells."],["dc.identifier.doi","10.1111/j.1600-065X.2007.00539.x"],["dc.identifier.isi","000247924700017"],["dc.identifier.pmid","17624956"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/50851"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","0105-2896"],["dc.title","Ca2+ signaling in antigen receptor-activated B lymphocytes"],["dc.type","review"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","41"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of Experimental Medicine"],["dc.bibliographiccitation.lastpage","58"],["dc.bibliographiccitation.volume","210"],["dc.contributor.author","Schneppenheim, Janna"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Huettl, Susann"],["dc.contributor.author","Luellmann-Rauch, Renate"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Eskelinen, Eeva-Liisa"],["dc.contributor.author","Hermans-Borgmeyer, Irm"],["dc.contributor.author","Fluhrer, Regina"],["dc.contributor.author","Saftig, Paul"],["dc.contributor.author","Schroeder, Bernd"],["dc.date.accessioned","2018-11-07T09:29:12Z"],["dc.date.available","2018-11-07T09:29:12Z"],["dc.date.issued","2013"],["dc.description.abstract","Regulated intramembrane proteolysis is a central cellular process involved in signal transduction and membrane protein turnover. The presenilin homologue signal-peptide-peptidase-like 2a (SPPL2a) has been implicated in the cleavage of type 2 transmembrane proteins. We show that the invariant chain (li, CD74) of the major histocompatability class II complex (MHCII) undergoes intramembrane proteolysis mediated by SPPL2a. B lymphocytes of SPPL2a(-/-) mice accumulate an N-terminal fragment (NTF) of CD74, which severely impairs membrane traffic within the endocytic system and leads to an altered response to B cell receptor stimulation, reduced BAFF-R surface expression, and accumulation of MHCII in transitional developmental stage T1 B cells. This results in significant loss of B cell subsets beyond the T1 stage and disrupted humoral immune responses, which can be recovered by additional ablation of CD74. Hence, we provide evidence that regulation of CD74-NTF levels by SPPL2a is indispensable for B cell development and function by maintaining trafficking and integrity of MHCII-containing endosomes, highlighting SPPL2a as a promising pharmacological target for depleting and/or modulating B cells."],["dc.identifier.isi","000313560900006"],["dc.identifier.pmid","23267015"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/30966"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Rockefeller Univ Press"],["dc.relation.issn","0022-1007"],["dc.title","The intramembrane protease SPPL2a promotes B cell development and controls endosomal traffic by cleavage of the invariant chain"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3620"],["dc.bibliographiccitation.issue","17"],["dc.bibliographiccitation.journal","The EMBO Journal"],["dc.bibliographiccitation.lastpage","3634"],["dc.bibliographiccitation.volume","30"],["dc.contributor.author","Oellerich, Thomas"],["dc.contributor.author","Bremes, Vanessa"],["dc.contributor.author","Neumann, Konstantin"],["dc.contributor.author","Bohnenberger, Hanibal"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Hsiao, He-Hsuan"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Schnyder, Tim"],["dc.contributor.author","Batista, Facundo D."],["dc.contributor.author","Urlaub, Henning"],["dc.contributor.author","Wienands, Juergen"],["dc.date.accessioned","2018-11-07T08:53:03Z"],["dc.date.available","2018-11-07T08:53:03Z"],["dc.date.issued","2011"],["dc.description.abstract","Spleen tyrosine kinase Syk and its substrate SLP65 (also called BLNK) are proximal signal transducer elements of the B-cell antigen receptor (BCR). Yet, our understanding of signal initiation and processing is limited owing to the incomplete list of SLP65 interaction partners and our ignorance of their association kinetics. We have now determined and quantified the in vivo interactomes of SLP65 in resting and stimulated B cells by mass spectrometry. SLP65 orchestrated a complex signal network of about 30 proteins that was predominantly based on dynamic interactions. However, a stimulation-independent and constant association of SLP65 with the Cbl-interacting protein of 85 kDa (CIN85) was requisite for SLP65 phosphorylation and its inducible plasma membrane translocation. In the absence of a steady SLP65/CIN85 complex, BCR-induced Ca(2+) and NF-kappa B responses were abrogated. Finally, live cell imaging and co-immunoprecipitation experiments further confirmed that both SLP65 and CIN85 are key components of the BCR-associated primary transducer module required for the onset and progression phases of BCR signal transduction. The EMBO Journal (2011) 30, 3620-3634. doi:10.1038/emboj.2011.251; Published online 5 August 2011"],["dc.identifier.doi","10.1038/emboj.2011.251"],["dc.identifier.isi","000294460000015"],["dc.identifier.pmid","21822214"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7839"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/22317"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Nature Publishing Group"],["dc.relation.issn","0261-4189"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","The B-cell antigen receptor signals through a preformed transducer module of SLP65 and CIN85"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]