@phdthesis{RamirezPineda2003, author = {Ramirez Pineda, Jos{\´e} Robinson}, title = {Dendritic cells activated by CpG motifs are potent inducers of a Th1 immune response that protects mice against leishmaniasis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-8410}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2003}, abstract = {The present investigation report a protocol to obtain dendritic cells (DC) that protects mice against fatal leishmaniasis. DC were generated from bone marrow precursors, pulsed with leishmanial antigen and activated with CpG oligodeoxinucleotides. Mice that were vaccinated with these cells were strongly protected against the clinical and parasitological manifestations of leishmaniasis and developed a Th1 immune response. protection was solid and long-lasting, and was also dependent of the via of administration. Whe the mechanism of protection was studied, it was observed that the availability of the cytokine interleukin-12 at the time of vaccination was a key requirement, but that the source of this cytokine is not the donor cells but unidentified cells from the recipients.}, subject = {Leishmaniose}, language = {en} } @phdthesis{Prusko2006, author = {Prusko, Carsten Dietmar}, title = {Evolutionary Diversification of Protein Functions : From Translation in Prokaryotes to Innate Immunity in Invertebrates}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-18517}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {With the progress in sequencing of the honey bee genome new data become available which allows the search and identification of genes coding for homologous proteins found in other organism. Two genes coding for c-type lysozymes were identified in the genome of A. mellifera through an online-based BLAST search. Expression of both intron-less genes seems not to be under the regulatory control of either of the two pathways involved in humoral insect immunity, i.e. Toll and Imd, since no NF-\&\#954;B transcription factor binding sites are found upstream of the genes. The encoded Lys-1 and Lys-2 are 157 and 143 amino acid long, respectively, and share a sequence similarity of 90\%. Further in silico analysis revealed a signal peptidase cleavage site at the N-terminus of each amino acid sequence, strongly suggesting a secretion of the enzymes into the surrounding environment of the producing cells. Sequence alignments of both amino acid sequences with other c-type lysozymes identified the highly conserved active site glutamic acid (Glu32) as well as eight highly conserved cysteine residues. However, an important aspartic acid (Asp50) in the active site that helps to stabilize a substrate intermediate during catalysis is replaced by a serine residue in the lysozymes of A. mellifera. The replacement of the active site aspartic acid in the honey bee lysozymes suggests a different catalytic mechanism and/or a different substrate-specificity in respect to other c-type lysozymes. Furthermore, 3D-models of Lys-1 and Lys-2 were generated based on the sequence similarity of A. mellifera lysozymes with other c-type lysozymes. The published 3D structure of the lysozyme from the silkmoth Bombyx mori, which shares the highest sequence similarity of all available structures with A. mellifera lysozymes, was used as template for the construction of the 3D-models. The models of Lys-1 and Lys-2 suggest that both enzymes resemble, in large part, the structure of B. mori lysozyme. In order to identify the set of AMPs in the hemolymph of A. mellifera, hemolymph of immunized bees was analyzed. Applying SDS-polyacrylamide gel electrophoresis and mass spectrometry on hemolymph from immunized bees, three out of the four peptides were identified, i.e. abaecin, defensin 1 and hymenoptaecin. Furthermore, Lys-2 was identified in the hemolymph by mass spectrometry, conclusively demonstrating the presence of a lysozyme in the hemolymph of A. mellifera for the first time. However, the protein levels of Lys-2 were not affected by bacterial injection, suggesting that the gene expression of the putative antibacterial protein is not under the regulatory control of the Imd and/or Toll pathway. Besides the abovementioned antimicrobial peptides, the 76 kDa large transferrin was also identified. Transferrin is an iron-binding protein that has been implicated in innate immunity in the honey bee. Furthermore, the effect of pathogenic dose, the timeline of peptide induction and the age-related accumulation of the aforementioned AMPs were studied. The intensity of expression of the antimicrobial peptides, abaecin, defensin 1, and hymenoptaecin as well as transferrin increased proportionally with the amount of bacteria injected into the hemocoel. No such effect was observed for the protein levels of Lys-2. Furthermore, up-regulation of the three antibacterial peptides and transferrin was observed within the first 24 h following infection with E. coli (gram-). Infection with the gram+ bacterium Micrococcus flavus resulted in high and moderate protein levels for transferrin and abaecin, respectively, whereas hardly any accumulation of hymenoptaecin was observed, indicating that the gene expression of abaecin and transferrin is somehow positively correlated, and would suggest a shared regulatory pathway that differs from that of hymenoptaecin. Although bacterial infections didn't seem to stimulate the production of Lys-2, different concentrations in the hemolymph were observed in bees of different ages, suggesting a correlation between the expression of Lys-2 and the age-related division of labor of adult worker honey bees, also known as age polyethism. The results further allow a proposed causal connection between the age-dependent accumulation of Lys-2 and the hemolymph titer of the gonotrophic hormone juvenile hormone, which is the "behavioral pacemaker" in adult honey bees.}, subject = {Biene}, language = {en} } @phdthesis{Mayer2006, author = {Mayer, Katrin Doris}, title = {Visualization of type I immunity using bicistronic IFN-gamma reporter mice in vitro and in vivo}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-19415}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Typ I Immunantworten, wie z.B. gegen Influenza Virus, Sendai Virus aber auch gegen intrazellul{\"a}re Erreger wie Toxoplasma gondii sind klassischerweise durch robuste IFN-\&\#947; Expression gekennzeichnet. Th1 und CD8+ Effektor T Zellen z{\"a}hlen zu den Hauptproduzenten von IFN-\&\#947;. Im Zusammenhang mit Autoimmunerkrankungen, Immunpathologie aber auch Impfstoffentwicklung, ist es {\"u}beraus wichtig die Regulierung von IFN-\&\#947; zu verstehen. In der vorliegenden Arbeit wurde die IFN-\&\#947; Expression von CD4+ und CD8+ T Zellen detailliert charakterisiert. Des Weiteren wurde die Rolle des IFN-\&\#947; Rezeptors f{\"u}r die IFN-\&\#947; Expression von T Zellen untersucht. Unter Zuhilfenahme von bicistronischen IFN-\&\#947;-eYFP Reporter M{\"a}usen, welche die direkte Identifizierung und Isolierung von vitalen IFN-\&\#947; exprimierenden Zellen erm{\"o}glichen, wurde die Expression von IFN-\&\#947; in vitro und in vivo, nach Infektion mit den bereits erw{\"a}hnten Erregern,visualisiert. Die Expression des IFN-\&\#947;-eYFP Reporters zeichnete sich, sowohl in vitro als auch in vivo nach Infektion, durch ein {\"a}ußerst heterogenes Fluoreszenzspektrum aus. Die Helligkeit der Reporter Fluoreszenz korrelierte positiv mit der Menge an IFN-\&\#947; Transkripten und mit der Menge des sekretierten IFN-\&\#947; Proteins nach Stimulierung. Die Helligkeit des Reporters reflektierte das Potenzial zur IFN-\&\#947; Produktion, die eigentliche Sekretion war jedoch weitgehend abh{\"a}ngig von zus{\"a}tzlicher Stimulierung durch Antigen. Des Weiteren korrelierte die Helligkeit des Reporters mit der zunehmenden Produktion von weiteren proinflammatorischen Zytokinen und Chemokinen. Hoch fluoreszente Zellen exprimierten zudem vermehrt Marker auf ihrer Oberflache, die auf akute Aktivierung hinweisen. Die am hellsten eYFP fluoreszierenden Zellen waren im Allgemeinen weiter ausdifferenziert und ihre Pr{\"a}senz war auf bestimmte Organe beschr{\"a}nkt. Die anatomische Begrenzung wurde durch den Erreger bestimmt. IFN-\&\#947; exprimierende Zellen wurden nach Infektion mit Sendai Virus oder Toxoplasma gondii in IFN-\&\#947; Rezeptor defizienten Reporter M{\"a}usen generiert. Die Frequenz und die Helligkeit der eYFP Reporter Expression waren jedoch ver{\"a}ndert. Experimente mit dualen Knochenmarks-Chim{\"a}ren M{\"a}usen, welche mit Wild-Typ und IFN-\&\#947; Rezeptor defizientem Knochenmark rekonstituiert wurden, ergaben eine T Zell-intrinsische Abh{\"a}ngigkeit von IFN-\&\#947; Rezeptor vermittelten Signalen f{\"u}r die Expression von IFN-\&\#947;. Die Helligkeit des Reporters dagegen wurde unabh{\"a}ngig von dem IFN-\&\#947; Rezeptor reguliert. Abschließend wurde ein Modell f{\"u}r die Expression von IFN-\&\#947; in CD4+ und CD8+ T Zellen entwickelt. Zusammenfassend f{\"u}hren diese Ergebnisse zu dem Schluss, dass die Expression von IFN-\&\#947; in CD4+ und CD8+ T Zellen und nach viraler oder parasit{\"a}rer Infektion unterschiedlich reguliert wird. Zus{\"a}tzlich wurde gezeigt, dass der IFN-\&\#947; Rezeptor an der \&\#65279;Modulation der IFN-\&\#947; Expression beteiligt ist.}, subject = {Interferon }, language = {en} } @phdthesis{Guenzel2009, author = {Guenzel, Carolin Alexandra}, title = {The Characterization of Nipah Virus V and W proteins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-37627}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {The work of the previous chapters describes the role of Nipah virus (NiV) V and W proteins regarding their role in interferon antagonism and regulation of viral replication. Previous publications have shown that NiV encodes IFN antagonist activity in its V, W and C protein (Park et al., 2003b; Rodriguez et al., 2002). In order to study the effect of both NiV proteins in the context of a virus infection, recombinant Newcastle disease viruses (rNDVs) expressing NiV V or NiV W were constructed. As a control virus served rNDV expressing NDV V proteins, which behaved like wildtype NDV. Growth kinetic experiments demonstrated that rNDVs expressing NiV V or W grew to higher titers than rNDV expressing NDV V in human A549 cells. This result suggested that both NiV V and W were able to render the avian virus, which normally does not replicate well in human cells, into a better growing virus. This hypothesis was supported by the fact that all rNDVs grew similarly in avian DF1 or Vero cells. When rNDV-infected A549 cells were specifically stained for NiV V or W protein it was observed that V is localized in the cytoplasm whereas W could be predominantly found in the nucleus. This observation was in agreement with previous studies reporting a nucleus export signal (NES) for NiV V and a nuclear localization signal (NLS) for NiV W (Rodriguez et al., 2004; Shaw et al., 2005). The specific localization of each NiV protein has also been shown to contribute to different functions in terms of IFN antagonism (Shaw et al., 2005). Here, NiV V and W proteins caused a severe attenuation of the immune response in rNDV-infected human A549 and dendritic cells. The transcription of type I interferons and ISGs was significantly downregulated in the presence of NiV V and W proteins. As a consequence of the transcriptional block, there was also an inhibition at the level of translation (as seen for A549 cells) and the secretion of IFNs and cytokines/chemokines (as seen for DCs). In contrast, NDV V protein induced a host immune response. Both NiV V and W also displayed a strong inhibitory effect on the function DCs. DCs represent a very important cell class because they link the innate immune response to the adaptive immune response (Banchereau \& Steinman, 1998). By downregulating the production and secretion of important cytokines/chemokines that are important for the activation of B and T lymphocytes, NiV V and W were able to disrupt that link. Interestingly, NiV W seemed to be a stronger inhibitor than NiV V in both A549 cells and DCs. Overall, it was demonstrated that NiV V and W were able to prevent the induction of the innate and adaptive host immune response cascade by inhibiting the transcription of immune genes in DCs and A549 cells. The second part of this work addressed the question whether NiV V and W proteins have a regulatory role in viral replication. This has been previously reported for Nipah virus itself (Sleeman et al., 2008) and other viruses (Atreya et al., 1998; Horikami et al., 1996; Witko et al., 2006). In order to study the ability of the V and W proteins of NiV to regulate viral transcription and/or replication, an existing NiV minireplicon assay was used (Halpin et al., 2004). Here, it was shown that NiV V and W (but not C) proteins significantly downregulated NiV minireplicon activity. The common N terminal region was shown to harbor the inhibitory activity. Co-immunoprecipitation experiments showed that both NiV V and W (but not C) were able to interact with NiV N, one component of the NiV polymerase. This result was supported by immunofluorescence experiments that revealed co-localization of NiV N with V and W. The binding of NiV V or W to NiV N occurred via their N terminus and more specifically amino acids 1-50. This suggested that V and W might inhibit viral replication by interacting with the viral polymerase resulting in a loss of function. Exact mechanisms still have to be elucidated.}, subject = {Viren}, language = {en} } @phdthesis{Boehme2009, author = {B{\"o}hme, Linda}, title = {Cellular response to double-stranded RNA in Chlamydia trachomatis-infected human host cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-46474}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2009}, abstract = {Chlamydien sind Gram-negative, obligat-intrazellul{\"a}re Bakterien, die f{\"u}r ein weites Spektrum an relevanten Krankheiten verantwortlich sind. Auf Grund ihres zweiphasigen Entwicklungszyklusses sind Chlamydien von einer intakten Wirtszelle abh{\"a}ngig, um sich erfolgreich vermehren und im Organismus ausbreiten zu k{\"o}nnen. Daher haben Chlamydien anspruchsvolle Strategien entwickelt, um das Immunsystem des Wirtes auszuschalten oder den programmierten Zelltod ihrer Wirtszelle zu verhindern. In der vorliegenden Arbeit wurde untersucht, ob eine Infektion mit C. trachomatis einen Einfluss auf die zellul{\"a}re Antwort auf dsRNA nehmen kann. Die Synthese von dsRNA ist ein charakteristisches Merkmal der Replikation von Viren, welche sowohl die Apoptose induzieren als auch das Immunsystem aktivieren kann. Um eine chlamydiale und virale Co-Infektion zu simulieren, wurden Chlamydien-infizierte Epithelzellen mit der synthetischen dsRNA Polyinosin-Polycytidins{\"a}ure (polyI:C) transfiziert. Im ersten Teil der Arbeit wurde untersucht, ob Chlamydien die durch dsRNA eingeleitete Apoptose verhindern k{\"o}nnen. Eine signifikante Reduktion der dsRNA-induzierten Apoptose konnte in infizierten Zellen beobachtet werden. Es zeigte sich, dass die Prozessierung der Initiator-Caspase-8 in infizierten Zellen unterblieb. Dies war von der fr{\"u}hen bakteriellen Proteinsynthese abh{\"a}ngig und f{\"u}r die dsRNA-vermittelte Apoptose spezifisch, da der durch TNFalpha bewirkte Zelltod nicht auf der Ebene der Caspase-8 verhindert werden konnte. Die Aktivierung von zellul{\"a}ren Faktoren, die bei der Apoptoseinduzierung eine wichtige Rolle spielen, beispielsweise PKR und RNase L, war in infizierten Zellen jedoch unver{\"a}ndert. Stattdessen konnte durch RNA Interferenz-vermittelte Depletion gezeigt werden, dass der zellul{\"a}re Caspase-8-Inhibitor cFlip eine entscheidende Rolle bei der chlamydialen Blockierung der dsRNA-vermittelten Apoptose spielt. Mittels Co-Immunopr{\"a}zipitation konnte ein erster Hinweis darauf gefunden werden, dass C. trachomatis eine Anreicherung von cFlip im dsRNA-induzierten Komplex von Caspase-8 und FADD bewirkt. Im zweiten Teil der Arbeit wurde untersucht, ob Chlamydien die Immunantwort auf virale Infektionen beeinflussen, welche vor allem die Expression von Interferonen und Interleukinen beinhaltet. Es stellte sich heraus, dass die Aktivierung des Interferon regulatory factor 3 (IRF-3) und des zur Familie von NF-kappaB Trankriptionsfaktoren geh{\"o}renden p65, zwei zentralen Regulatoren der Immunantwort auf dsRNA, in infizierten Epithelzellen ver{\"a}ndert war. Die Degradation von IkappaB-alpha, des Inhibitors von NF-kappaB, war in infizierten Zellen beschleunigt, begleitet von einer Ver{\"a}nderung der Translokation des Transkriptionsfaktors in den Zellkern. Im Gegensatz dazu wurde die nukle{\"a}re Translokation von IRF-3 durch die Infektion signifikant verhindert. Die hier vorgestellten Daten zeigen erstmals, dass eine Infektion mit C. trachomatis die zellul{\"a}re Antwort auf dsRNA signifikant ver{\"a}ndern kann und implizieren einen Einfluss von chlamydialen Infektionen auf den Ausgang von viralen Superinfektionen.}, subject = {Chlamydia trachomatis}, language = {en} } @phdthesis{TranVan2010, author = {Tran-Van, Hieu}, title = {Semaphorin receptors in the immunological synapse: regulation and measles virus-driven modulation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-53926}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2010}, abstract = {J{\"a}hrlich gehen ca. 164000 Todesf{\"a}lle (WHO, 2008) auf eine Infektion mit Masernviren (MV) zur{\"u}ck. Die Hauptursache f{\"u}r den t{\"o}dlichen Verlauf der Krankheit ist die MV-induzierte Immunsuppression, deren zugrunde liegende Mechanismen noch nicht v{\"o}llig aufgekl{\"a}rt sind. Es gibt Hinweise darauf, dass MV einerseits die Funktionalit{\"a}t von T-Zellen beeintr{\"a}chtigt, indem es die Aktindynamik behindert, und andererseits dendritische Zellen (DC) infiziert, was dazu f{\"u}hrt, dass sie T-Zellen nicht mehr vollst{\"a}ndig aktivieren k{\"o}nnen. W{\"a}hrend der Entwicklung bzw. des Wachstums von Neuronen kommt es zum Kollaps wachsender Dendriten, wenn Semaphorine (insbesondere SEMA3A) an den Rezeptor Plexin-A1 (plexA1) und seinem Korezeptor Neuropilin-1 (NP-1) binden. Dieser Kollaps wird durch interferenz mit der Aktindynamik verursacht. In dieser Studie wurde die Funktion dieser drei Molek{\"u}le in Immunzellen bzw. ihre Rolle in der MV-induzierten Immunsuppression untersucht. Es konnte gezeigt werden, dass plexA1 eine wichtige Komponente der humanen immunologischen Synapse (IS) ist. Nach CD3/CD28-Ligation kommt es zur transienten Translokation zur T-Zelloberfl{\"a}che und zur Akkumulation an der Kontaktfl{\"a}che zwischen T-Zelle und DC bzw. α-CD3/CD28 beschichteten Mikropartikeln. Wird die plexA1-Expression inhibiert (RNAi) oder die plexA1-Funktion gest{\"o}rt (exogenes Blockieren oder Expression einer dominant negativen Mutante), ist die T-Zellexpansion reduziert. Nach MV-Exposition ist die Translokation von plexA1 und NP-1, ebenfalls einem wichtigen Bestandteil der immunologischen Synapse, zur Kontaktfl{\"a}che auf T-Zellseite gest{\"o}rt. Des Weiteren behindert eine MV-Infektion den plexA1/NP-1-Metabolismus in reifenden DC und f{\"u}hrt zus{\"a}tzlich zu einer fr{\"u}hen und starken Aussch{\"u}ttung von SEMA3A durch DC, insbesondere in Gegenwart allogener T-Zellen. Durch rasterelektronenmikroskopische Aufnahmen wurde gezeigt, dass SEMA3A einen transienten Verlust aktinbasierter Zellforts{\"a}tze bei T-Zellen zur Folge hat. Zus{\"a}tzlich reduziert SEMA3A das chemotaktische Migrationsverhalten von DC und T Zell und die Frequenz ihrer Konjugat-Bildung. Zusammenfassend stellt sich die Situation so dar, dass MV die Semaphorinrezeptorfunktion zum einen dadurch beeintr{\"a}chtigt, dass es die Rekrutierung der Rezeptoren zur IS verhindert und zum anderen zur verfr{\"u}hten Aussch{\"u}ttung des kollapsinduzierenden Liganden SEMA3A f{\"u}hrt. Beide Ph{\"a}nomene k{\"o}nnten einen wichtigen Beitrag zur MV-induzierten Immunsuppression leisten.}, subject = {Masernvirus}, language = {en} } @phdthesis{Gupta2018, author = {Gupta, Shishir Kumar}, title = {Re-annotation of Camponotus floridanus Genome and Characterization of Innate Immunity Transcriptome Responses to Bacterial Infections}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-140168}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2018}, abstract = {The sequencing of several ant genomes within the last six years open new research avenues for understanding not only the genetic basis of social species but also the complex systems such as immune responses in general. Similar to other social insects, ants live in cooperative colonies, often in high densities and with genetically identical or closely related individuals. The contact behaviours and crowd living conditions allow the disease to spread rapidly through colonies. Nevertheless, ants can efficiently combat infections by using diverse and effective immune mechanisms. However, the components of the immune system of carpenter ant Camponotus floridanus and also the factors in bacteria that facilitate infection are not well understood. To form a better view of the immune repository and study the C. floridanus immune responses against the bacteria, experimental data from Illumina sequencing and mass-spectrometry (MS) data of haemolymph in normal and infectious conditions were analysed and integrated with the several bioinformatics approaches. Briefly, the tasks were accomplished in three levels. First, the C. floridanus genome was re-annotated for the improvement of the existing annotation using the computational methods and transcriptomics data. Using the homology based methods, the extensive survey of literature, and mRNA expression profiles, the immune repository of C. floridanus were established. Second, large-scale protein-protein interactions (PPIs) and signalling network of C. floridanus were reconstructed and analysed and further the infection induced functional modules in the networks were detected by mapping of the expression data over the networks. In addition, the interactions of the immune components with the bacteria were identified by reconstructing inter-species PPIs networks and the interactions were validated by literature. Third, the stage-specific MS data of larvae and worker ants were analysed and the differences in the immune response were reported. Concisely, all the three omics levels resulted to multiple findings, for instance, re-annotation and transcriptome profiling resulted in the overall improvement of structural and functional annotation and detection of alternative splicing events, network analysis revealed the differentially expressed topologically important proteins and the active functional modules, MS data analysis revealed the stage specific differences in C. floridanus immune responses against bacterial pathogens. Taken together, starting from re-annotation of C. floridanus genome, this thesis provides a transcriptome and proteome level characterization of ant C. floridanus, particularly focusing on the immune system responses to pathogenic bacteria from a biological and a bioinformatics point of view. This work can serve as a model for the integration of omics data focusing on the immuno-transcriptome of insects.}, subject = {Camponotus floridanus}, language = {en} } @phdthesis{Gaal2022, author = {Gaal, Chiara Claudia}, title = {Cardiac Antigens and T cell Specificity after Experimental Myocardial Infarction in Mice}, doi = {10.25972/OPUS-26004}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-260047}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2022}, abstract = {Cardiovascular diseases (CVD), subsuming atherosclerosis of the coronary arteries and subsequent myocardial infarction, are the leading cause of death in the European Union (over 4 million deaths annually), with devastating individual and economic consequences. Recent studies revealed that T cells play a crucial role in post-MI inflammation, healing and remodelling processes. Nevertheless, the specificity profile of adaptive immune responses in the infarcted myocardium has not yet been differentiated. The experiments portrayed in this thesis sought to assess whether post-MI CD4+ T cell responses in mice are triggered by heart specific antigens, and eventually identify relevant epitopes. We were able to create a murine antigen atlas including a list of 206 epitopes for I-Ab and 193 epitopes for I-Ad presented on MHC-II in the context of MI. We sought to consecutively test this panel by in vitro T cell proliferation and antigen recall assays ex vivo. The elispot assay was used as a readout for antigen-specific stimulation by measurement of IL-2 and IFN-γ production, currently the most sensitive approach available to detect even small counts of antigen producing cells. Splenocytes as well as lymphocytes from mediastinal lymph nodes were purified from animals 7 days or 56 days after EMI conducted by ligation of the left anterior descending artery. We were able to provide evidence that post-MI T cell responses in Balb/c mice are triggered by heart-specific antigens and that MYHCA, especially MYHCA614-628, is relevant for that response. Moreover, a significant specific T cell response after MI in C57BL/6J mice was observed for α actin, cardiac muscle 1 [ACTC1], myosin-binding protein C3 [MYBPC3] and myosin heavy chain α [MYHCA] derived heart specific antigens. Generally, the epitopes of interest for Balb/c as well as C57BL/6J could be further investigated and may eventually be modulated in the future.}, subject = {Regulatorische T-Lymphozyt}, language = {en} } @phdthesis{Gotthard2023, author = {Gotthard, Hannes}, title = {Targeting Colorectal Cancer Stem Cells with Hemibodies}, doi = {10.25972/OPUS-30309}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-303090}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {The cancer stem cell hypothesis is a cancer development model which elicited great interest in the last decades stating that cancer heterogeneity arises from a stem cell through asymmetrical division. The Cancer Stem Cell subset is described as the only population to be tumorigenic and having the potential to renew. Conventional therapy often fails to eradicate CSC resulting in tumor relapse. Consequently, it is of great inter-est to eliminate this subset of cells to provide the best patient outcome. In the last years several approaches to target CSC were developed, one of them being immunotherapeu-tic targeting with antibodies. Since markers associated with CSC are also expressed on normal stem cells or healthy adjacent tissue in colorectal cancer, dual targeting strate-gies are preferred over targeting only a single antigen. Subsequently, the idea of dual targeting two CSC markers in parallel by a newly developed split T cell-engaging anti-body format termed as Hemibodies emerged. In a preliminary single cell RNA sequenc-ing analysis of colorectal cancer cells CD133, CD24, CD166 and CEA were identified as suitable targets for the combinatorial targeting strategy. Therefore, this study focused on trispecific and trivalent Hemibodies comprising a split binding moiety against CD3 and a binding moiety against either CD133, CD24, CD166 or CEA to overcome the occurrence of resistance and to efficiently eradicate all tumor cells including the CSC compartment. The study showed that the Hemibody combinations CD133xCD24, CD133xCD166 and CD133xCEA are able to eliminate double positive CHO cells with high efficacy while having a high specificity indicated by no killing of single antigen positive cells. A thera-peutic window ranging between one to two log levels could be achieved for all combina-tions mentioned above. The combinations CD133xCD24 and CD133xCD166 further-more proved its efficacy and specificity on established colorectal cancer cell lines. Be-sides the evaluation of specificity and efficacy the already introduced 1st generation of Hemibodies could be improved into a 2nd generation Hemibody format with increased half-life, stability and production yield. In future experiments the applicability of above-mentioned Hemibodies will be proven on patient-derived micro tumors to also include variables like tumor microenvironment and infiltration.}, subject = {Monoklonaler bispezifischer Antik{\"o}rper}, language = {en} }