@article{VandenHoveJakobSchrautetal.2011, author = {Van den Hove, Daniel and Jakob, Sissi Brigitte and Schraut, Karla-Gerlinde and Kenis, Gunter and Schmitt, Angelika Gertrud and Kneitz, Susanne and Scholz, Claus-J{\"u}rgen and Wiescholleck, Valentina and Ortega, Gabriela and Prickaerts, Jos and Steinbusch, Harry and Lesch, Klaus-Peter}, title = {Differential Effects of Prenatal Stress in 5-Htt Deficient Mice: Towards Molecular Mechanisms of Gene x Environment Interactions}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75795}, year = {2011}, abstract = {Prenatal stress (PS) has been shown to influence the development of the fetal brain and to increase the risk for the development of psychiatric disorders in later life. Furthermore, the variation of human serotonin transporter (5-HTT, SLC6A4) gene was suggested to exert a modulating effect on the association between early life stress and the risk for depression. In the present study, we used a 5-Htt6PS paradigm to investigate whether the effects of PS are dependent on the 5-Htt genotype. For this purpose, the effects of PS on cognition, anxiety- and depression-related behavior were examined using a maternal restraint stress paradigm of PS in C57BL6 wild-type (WT) and heterozygous 5-Htt deficient (5-Htt +/2) mice. Additionally, in female offspring, a genome-wide hippocampal gene expression profiling was performed using the Affymetrix GeneChipH Mouse Genome 430 2.0 Array. 5-Htt +/2 offspring showed enhanced memory performance and signs of reduced anxiety as compared to WT offspring. In contrast, exposure of 5-Htt +/2 mice to PS was associated with increased depressive-like behavior, an effect that tended to be more pronounced in female offspring. Further, 5-Htt genotype, PS and their interaction differentially affected the expression of numerous genes and related pathways within the female hippocampus. Specifically, MAPK and neurotrophin signaling were regulated by both the 5-Htt +/2 genotype and PS exposure, whereas cytokine and Wnt signaling were affected in a 5-Htt genotype6PS manner, indicating a gene6environment interaction at the molecular level. In conclusion, our data suggest that although the 5-Htt +/2 genotype shows clear adaptive capacity, 5-Htt +/2 mice -particularly females- at the same time appear to be more vulnerable to developmental stress exposure when compared to WT offspring. Moreover, hippocampal gene expression profiles suggest that distinct molecular mechanisms mediate the behavioral effects of the 5-Htt genotype, PS exposure, and their interaction.}, subject = {Medizin}, language = {en} } @article{BeyrichLoefflerKobsaretal.2011, author = {Beyrich, Claudia and L{\"o}ffler, J{\"u}rgen and Kobsar, Anna and Speer, Christian P. and Kneitz, Susanne and Eigenthaler, Martin}, title = {Infection of Human Coronary Artery Endothelial Cells by Group B Streptococcus Contributes to Dysregulation of Apoptosis, Hemostasis, and Innate Immune Responses [Research Article]}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68834}, year = {2011}, abstract = {Early onset sepsis due to group B streptococcus leads to neonatal morbidity, increased mortality, and long-term neurological deficencies. Interaction between septicemic GBS and confluent monolayers of human coronary artery endothelial cells (HCAECs) was analyzed by genome wide expression profiling. In total, 124 genes were differentially expressed (89 upregulated, 35 downregulated) based on a more than 3-fold difference to control HCAEC. Regulated genes are involved in apoptosis, hemostasis, oxidative stress response, infection, and inflammation. Regulation of selected genes and proteins identified in the gene array analysis was confirmed by Real-time RT-PCR assay (granulocy te chemotactic protein 2), ELISA (urokinase, cyclooxygenase 2, granulocyte chemotactic protein 1), and western blotting (Heme oxygenase1, BCL2 interacting protein) at various time points between 4 and 24 hours. These results indicate that GBS infection might influence signalling pathways leading to impaired function of the innate immune system and hemorrhagic and inflammatory complications during GBS sepsis.}, subject = {Medizin}, language = {en} } @article{LangenhorstGogishviliRibechinietal.2012, author = {Langenhorst, Daniela and Gogishvili, Tea and Ribechini, Eliana and Kneitz, Susanne and McPherson, Kirsty and Lutz, Manfred B. and H{\"u}nig, Thomas}, title = {Sequential induction of effector function, tissue migration and cell death during polyclonal activation of mouse regulatory T-cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76009}, year = {2012}, abstract = {The ability of CD4+Foxp3+ regulatory T-cells (Treg) to produce interleukin (IL)-10 is important for the limitation of inflammation at environmental interfaces like colon or lung. Under steady state conditions, however, few Tregs produce IL-10 ex vivo. To investigate the origin and fate of IL-10 producing Tregs we used a superagonistic mouse anti-mouse CD28 mAb (CD28SA) for polyclonal in vivo stimulation of Tregs, which not only led to their numeric expansion but also to a dramatic increase in IL-10 production. IL-10 secreting Tregs strongly upregulated surface receptors associated with suppressive function as compared to non-producing Tregs. Furthermore, polyclonally expanding Tregs shifted their migration receptor pattern after activation from a CCR7+CCR52 lymph node-seeking to a CCR72CCR5+ inflammationseeking phenotype, explaining the preferential recruitment of IL-10 producers to sites of ongoing immune responses. Finally, we observed that IL-10 producing Tregs from CD28SA stimulated mice were more apoptosis-prone in vitro than their IL-10 negative counterparts. These findings support a model where prolonged activation of Tregs results in terminal differentiation towards an IL-10 producing effector phenotype associated with a limited lifespan, implicating built-in termination of immunosuppression.}, subject = {Medizin}, language = {en} }