@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 (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.},
  language  = {en}
}
@article{GlaserSilwedelFehrholzetal.2017,
  author    = {Glaser, Kirsten and Silwedel, Christine and Fehrholz, Markus and Waaga-Gasser, Ana M. and Henrich, Birgit and Claus, Heike and Speer, Christian P.},
  title     = {Ureaplasma Species Differentially Modulate Pro- and Anti-Inflammatory Cytokine Responses in Newborn and Adult Human Monocytes Pushing the State Toward Pro-Inflammation},
  series = {Frontiers in Cellular and Infection Microbiology},
  volume    = {7},
  journal   = {Frontiers in Cellular and Infection Microbiology},
  number    = {484},
  doi       = {10.3389/fcimb.2017.00484},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-169958},
  year      = {2017},
  abstract  = {Background: Ureaplasma species have been associated with chorioamnionitis and preterm birth and have been implicated in the pathogenesis of neonatal short and long-term morbidity. However, being mostly commensal bacteria, controversy remains on the pro-inflammatory capacity of Ureaplasma. Discussions are ongoing on the incidence and impact of prenatal, perinatal, and postnatal infection. The present study addressed the impact of Ureaplasma isolates on monocyte-driven inflammation. Methods: Cord blood monocytes of term neonates and adult monocytes, either native or LPS-primed, were cultured with Ureaplasma urealyticum (U. urealyticum) serovar 8 (Uu8) and Ureaplasma parvum serovar 3 (Up3). Using qRT-PCR, cytokine flow cytometry, and multi-analyte immunoassay, we assessed mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-12p40, IL-10, and IL-1 receptor antagonist (IL-1ra) as well as Toll-like receptor (TLR) 2 and TLR4. Results: Uu8 and Up3 induced mRNA expression and protein release of TNF-α, IL-1β and IL-8 in term neonatal and adult monocytes (p < 0.01 and p < 0.05). Intracellular protein expression of TNF-α, IL-1β and IL-8 in Ureaplasma-stimulated cells paralleled those results. Ureaplasma-induced cytokine levels did not significantly differ from LPS-mediated levels except for lower intracellular IL-1β in adult monocytes (Uu8: p < 0.05). Remarkably, ureaplasmas did not induce IL-12p40 response and promoted lower amounts of anti-inflammatory IL-10 and IL-1ra than LPS, provoking a cytokine imbalance more in favor of pro-inflammation (IL-1β/IL-10, IL-8/IL-10 and IL-8/IL-1ra: p < 0.01, vs. LPS). In contrast to LPS, both isolates induced TLR2 mRNA in neonatal and adult cells (p < 0.001 and p < 0.05) and suppressed TLR4 mRNA in adult monocytes (p < 0.05). Upon co-stimulation, Uu8 and Up3 inhibited LPS-induced intracellular IL-1β (p < 0.001 and p < 0.05) and IL-8 in adult monocytes (p < 0.01), while LPS-induced neonatal cytokines were maintained or aggravated (p < 0.05). Conclusion: Our data demonstrate a considerable pro-inflammatory capacity of Ureaplasma isolates in human monocytes. Stimulating pro-inflammatory cytokine responses while hardly inducing immunomodulatory and anti-inflammatory cytokines, ureaplasmas might push monocyte immune responses toward pro-inflammation. Inhibition of LPS-induced cytokines in adult monocytes in contrast to sustained inflammation in term neonatal monocytes indicates a differential modulation of host immune responses to a second stimulus. Modification of TLR2 and TLR4 expression may shape host susceptibility to inflammation.},
  language  = {en}
}
@article{GlaserGradzkaLuczewskaSzymankiewiczBreborowiczetal.2019,
  author    = {Glaser, Kirsten and Gradzka-Luczewska, Anna and Szymankiewicz-Breborowicz, Marta and Kawczynska-Leda, Natalia and Henrich, Birgit and Waaga-Gasser, Ana Maria and Speer, Christian P.},
  title     = {Perinatal ureaplasma exposure is associated with increased risk of late onset sepsis and imbalanced inflammation in preterm infants and may add to lung injury},
  series = {Frontiers in Cellular and Infection Microbiology},
  volume    = {9},
  journal   = {Frontiers in Cellular and Infection Microbiology},
  number    = {68},
  doi       = {10.3389/fcimb.2019.00068},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201270},
  year      = {2019},
  abstract  = {Background: Controversy remains concerning the impact of Ureaplasma on preterm neonatal morbidity. Methods: Prospective single-center study in very low birth weight infants <30 weeks' gestation. Cord blood and initial nasopharyngeal swabs were screened for Ureaplasma parvum and U. urealyticum using culture technique and polymerase chain reaction. Neonatal outcomes were followed until death or discharge. Multi-analyte immunoassay provided cord blood levels of inflammatory markers. Using multivariate regression analyses, perinatal Ureaplasma exposure was evaluated as risk factor for the development of bronchopulmonary dysplasia (BPD), other neonatal morbidities until discharge and systemic inflammation at admission. Results: 40/103 (39\%) infants were positive for Ureaplasma in one or both specimens, with U. parvum being the predominant species. While exposure to Ureaplasma alone was not associated with BPD, we found an increased risk of BPD in Ureaplasma-positive infants ventilated ≥5 days (OR 1.64; 95\% CI 0.12-22.98; p = 0.009). Presence of Ureaplasma was associated with a 7-fold risk of late onset sepsis (LOS) (95\% CI 1.80-27.39; p = 0.014). Moreover, Ureaplasma-positive infants had higher I/T ratios (b 0.39; 95\% CI 0.08-0.71; p = 0.014), increased levels of interleukin (IL)-17 (b 0.16; 95\% CI 0.02-0.30; p = 0.025) and matrix metalloproteinase 8 (b 0.77; 95\% CI 0.10-1.44; p = 0.020), decreased levels of IL-10 (b -0.77; 95\% CI -1.58 to -0.01; p = 0.043) and increased ratios of Tumor necrosis factor-α, IL-8, and IL-17 to anti-inflammatory IL-10 (p = 0.003, p = 0.012, p < 0.001). Conclusions: Positive Ureaplasma screening was not associated with BPD. However, exposure contributed to BPD in infants ventilated ≥5 days and conferred an increased risk of LOS and imbalanced inflammatory cytokine responses.},
  language  = {en}
}