TY  - JOUR
A1  - Silwedel, Christine
A1  - Hütten, Matthias C.
A1  - Speer, Christian P.
A1  - Härtel, Christoph
A1  - Haarmann, Axel
A1  - Henrich, Birgit
A1  - Tijssen, Maud P. M.
A1  - Alnakhli, Abdullah Ahmed
A1  - Spiller, Owen B.
A1  - Schlegel, Nicolas
A1  - Seidenspinner, Silvia
A1  - Kramer, Boris W.
A1  - Glaser, Kirsten
T1  - Ureaplasma-driven neonatal neuroinflammation: novel insights from an ovine model
JF  - Cellular and Molecular Neurobiology
N2  - 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 (n = 10) or saline (n = 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.
KW  - Ureaplasma parvum
KW  - CNS integrity
KW  - neonatal meningitis
KW  - preterm birth
KW  - immaturity
KW  - animal model
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324285
VL  - 43
IS  - 2
ER  - 
TY  - JOUR
A1  - Silwedel, Christine
A1  - Speer, Christian P.
A1  - Haarmann, Axel
A1  - Fehrholz, Markus
A1  - Claus, Heike
A1  - Schlegel, Nicolas
A1  - Glaser, Kirsten
T1  - Ureaplasma species modulate cytokine and chemokine responses in human brain microvascular endothelial cells
JF  - International Journal of Molecular Science
N2  - Ureaplasma species are common colonizers of the adult genitourinary tract and often considered as low-virulence commensals. Intraamniotic Ureaplasma infections, however, facilitate chorioamnionitis and preterm birth, and cases of Ureaplasma-induced neonatal sepsis, pneumonia, and meningitis raise a growing awareness of their clinical relevance. In vitro studies are scarce but demonstrate distinct Ureaplasma-driven impacts on immune mechanisms. The current study addressed cytokine and chemokine responses upon exposure of native or lipopolysaccharide (LPS) co-stimulated human brain microvascular endothelial cells (HBMEC) to Ureaplasma urealyticum or U. parvum, using qRT-PCR, RNA sequencing, multi-analyte immunoassay, and flow cytometry. Ureaplasma exposure in native HBMEC reduced monocyte chemoattractant protein (MCP)-3 mRNA expression (p < 0.01, vs. broth). In co-stimulated HBMEC, Ureaplasma spp. attenuated LPS-evoked mRNA responses for C-X-C chemokine ligand 5, MCP-1, and MCP-3 (p < 0.05, vs. LPS) and mitigated LPS-driven interleukin (IL)-1α protein secretion, as well as IL-8 mRNA and protein responses (p < 0.05). Furthermore, Ureaplasma isolates increased C-X-C chemokine receptor 4 mRNA levels in native and LPS co-stimulated HBMEC (p < 0.05). The presented results may imply immunomodulatory capacities of Ureaplasma spp. which may ultimately promote chronic colonization and long-term neuroinflammation.
KW  - Ureaplasma urealyticum
KW  - Ureaplasma parvum
KW  - neuroinflammation
KW  - meningitis
KW  - blood–brain barrier
KW  - HBMEC
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201848
SN  - 1422-0067
VL  - 20
IS  - 14
ER  -