@article{SilwedelHuettenSpeeretal.2023, author = {Silwedel, Christine and H{\"u}tten, Matthias C. and Speer, Christian P. and H{\"a}rtel, Christoph and Haarmann, Axel and Henrich, Birgit and Tijssen, Maud P. M. and Alnakhli, Abdullah Ahmed and Spiller, Owen B. and Schlegel, Nicolas and Seidenspinner, Silvia and Kramer, Boris W. and Glaser, Kirsten}, title = {Ureaplasma-driven neonatal neuroinflammation: novel insights from an ovine model}, series = {Cellular and Molecular Neurobiology}, volume = {43}, journal = {Cellular and Molecular Neurobiology}, number = {2}, doi = {10.1007/s10571-022-01213-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324285}, pages = {785-795}, year = {2023}, abstract = {Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (nā€‰=ā€‰10) or saline (nā€‰=ā€‰11), lambs were surgically delivered at gestational day 128-129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C-X-C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood-brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.}, language = {en} } @article{RolfesRuckDavidetal.2022, author = {Rolfes, Leoni and Ruck, Tobias and David, Christina and Mencl, Stine and Bock, Stefanie and Schmidt, Mariella and Strecker, Jan-Kolja and Pfeuffer, Steffen and Mecklenbeck, Andreas-Schulte and Gross, Catharina and Gliem, Michael and Minnerup, Jens and Schuhmann, Michael K. and Kleinschnitz, Christoph and Meuth, Sven G.}, title = {Natural Killer Cells Are Present in Rag1\(^{-/-}\) Mice and Promote Tissue Damage During the Acute Phase of Ischemic Stroke}, series = {Translational Stroke Research}, volume = {13}, journal = {Translational Stroke Research}, number = {1}, issn = {1868-4483}, doi = {10.1007/s12975-021-00923-3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-308924}, pages = {197-211}, year = {2022}, abstract = {Rag1\(^{-/-}\) mice, lacking functional B and T cells, have been extensively used as an adoptive transfer model to evaluate neuroinflammation in stroke research. However, it remains unknown whether natural killer (NK) cell development and functions are altered in Rag1\(^{-/-}\) mice as well. This connection has been rarely discussed in previous studies but might have important implications for data interpretation. In contrast, the NOD-Rag1\(^{null}\)IL2rg\(^{null}\) (NRG) mouse model is devoid of NK cells and might therefore eliminate this potential shortcoming. Here, we compare immune-cell frequencies as well as phenotype and effector functions of NK cells in Rag1\(^{-/-}\) and wildtype (WT) mice using flow cytometry and functional in vitro assays. Further, we investigate the effect of Rag1\(^{-/-}\) NK cells in the transient middle cerebral artery occlusion (tMCAO) model using antibody-mediated depletion of NK cells and adoptive transfer to NRG mice in vivo. NK cells in Rag1\(^{-/-}\) were comparable in number and function to those in WT mice. Rag1\(^{-/-}\) mice treated with an anti-NK1.1 antibody developed significantly smaller infarctions and improved behavioral scores. Correspondingly, NRG mice supplemented with NK cells were more susceptible to tMCAO, developing infarctions and neurological deficits similar to Rag1-/- controls. Our results indicate that NK cells from Rag1-/- mice are fully functional and should therefore be considered in the interpretation of immune-cell transfer models in experimental stroke. Fortunately, we identified the NRG mice, as a potentially better-suited transfer model to characterize individual cell subset-mediated neuroinflammation in stroke.}, language = {en} }