TY  - JOUR
A1  - Twisselmann, Nele
A1  - Pagel, Julia
A1  - Künstner, Axel
A1  - Weckmann, Markus
A1  - Hartz, Annika
A1  - Glaser, Kirsten
A1  - Hilgendorff, Anne
A1  - Göpel, Wolfgang
A1  - Busch, Hauke
A1  - Herting, Egbert
A1  - Weinberg, Jason B.
A1  - Härtel, Christoph
T1  - Hyperoxia/Hypoxia Exposure Primes a Sustained Pro-Inflammatory Profile of Preterm Infant Macrophages Upon LPS Stimulation
JF  - Frontiers in Immunology
N2  - Preterm infants are highly susceptible to sustained lung inflammation, which may be triggered by exposure to multiple environmental cues such as supplemental oxygen (O\(_2\)) and infections. We hypothesized that dysregulated macrophage (MФ) activation is a key feature leading to inflammation-mediated development of bronchopulmonary dysplasia (BPD) in preterm infants. Therefore, we aimed to determine age-dependent differences in immune responses of monocyte-derived MФ comparing cord blood samples derived from preterm (n=14) and term (n=19) infants as well as peripheral blood samples from healthy adults (n=17) after lipopolysaccharide (LPS) exposure. Compared to term and adult MФ, LPS-stimulated preterm MФ showed an enhanced and sustained pro-inflammatory immune response determined by transcriptome analysis, cytokine release inducing a RORC upregulation due to T cell polarization of neonatal T cells, and TLR4 surface expression. In addition, a double-hit model was developed to study pulmonary relevant exposure factors by priming MФ with hyperoxia (O\(_2\) = 65%) or hypoxia (O\(_2\) = 3%) followed by lipopolysaccharide (LPS, 100ng/ml). When primed by 65% O\(_2\), subsequent LPS stimulation in preterm MФ led to an exaggerated pro-inflammatory response (e.g. increased HLA-DR expression and cytokine release) compared to LPS stimulation alone. Both, exposure to 65% or 3% O\(_2\) together with subsequent LPS stimulation, resulted in an exaggerated pro-inflammatory response of preterm MФ determined by transcriptome analysis. Downregulation of two major transcriptional factors, early growth response gene (Egr)-2 and growth factor independence 1 (Gfi1), were identified to play a role in the exaggerated pro-inflammatory response of preterm MФ to LPS insult after priming with 65% or 3% O\(_2\). Preterm MФ responses to LPS and hyperoxia/hypoxia suggest their involvement in excessive inflammation due to age-dependent differences, potentially mediated by downregulation of Egr2 and Gfi1 in the developing lung.
KW  - preterm infants
KW  - sustained inflammation
KW  - macrophages
KW  - hyperoxia
KW  - hypoxia
KW  - infection
KW  - bronchopulmonary dysplasia
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250356
SN  - 1664-3224
VL  - 12
ER  -